Friday, May 31, 2024

Planetary Protection: Why study it? What can it teach us about finding life beyond Earth?

Universe Today has recently investigated a plethora of scientific disciplines, including impact craters, planetary surfaces, exoplanets, astrobiology, solar physics, comets, planetary atmospheres, planetary geophysics, cosmochemistry, meteorites, radio astronomy, extremophiles, organic chemistry, black holes, and cryovolcanism, while conveying their importance of how each of them continues to teach researchers and the public about our place in the vast universe.

Here, we investigate the field of planetary protection, which involves preventing Earth-born organisms from contaminating other worlds or interfering with scientific analyses on those worlds, along with preventing contamination to Earth from returned samples. To investigate this, we present a 2023 paper in Acta Astronautica with additional insights from the study’s lead author, Dr. Athena Coustenis, who serves as the Chair of the Committee on Space Research (COSPAR) Panel on Planetary Protection (PPP), regarding what planetary protection can teach us about finding life beyond Earth, exciting aspects about planetary protection, and advice for upcoming students who wish to study planetary protection.

The paper discusses the importance of planetary protection regarding space exploration, stating, “Planetary protection enables scientific return from solar system bodies investigations and at the same time protects life on Earth. As we continue to explore our solar system by landing machines and humans on other planets, we need to ascertain that we do not bring potentially dangerous material home to Earth or carry anything from Earth that may contaminate another planetary body and prevent scientific investigations.”

The paper discusses in greater detail the COSPAR PPP and its primary goals, including offering advice or guidance to government or private space-faring organizations and ensuring extraterrestrial samples returned from outer space do not contaminate the Earth, and specifically its biosphere. Additionally, the paper discusses recent policy actions taken by the PPP for the continued exploration of the Moon, Mars, and icy moons such as Europa, Enceladus, and Titan.

For the Moon, PPP recommended steps that need to be taken to prevent potential contamination of the permanently shadowed regions of the Moon, which are hypothesized to contain large quantities of water ice and are of significant interest for the upcoming Artemis missions. For Mars, the PPP focused on safeguarding more advanced scientific endeavors, including drilling, older areas of Mars that have yet to be explored, and sample return missions, to prevent contamination of potential scientific results and Earth’s biosphere, as well.

For icy moons, which the paper notes as being “possible habitable environments”, the PPP has already expressed concerns about exploring these worlds with the Planetary Protection of the Outer Solar System (PPOOS), which was led by the European Science Foundation and funded by the European Commission and is in the process of seeking additional insights in the future. Therefore, with these intriguing worlds being considered for exploration, what can planetary protection teach us about finding life beyond Earth?

Dr. Coustenis tells Universe Today, “Finding ways to preserve scientific research in our solar system helps the quest for finding life elsewhere and protecting our own biosphere during space exploration is essential for life on Earth. Working to that end with a large group of scientists, agency representatives and other expert stakeholders is one of the most rewarding activities in my career. The valuable outcome which represents thorough, long-term studies and reviews of knowledge is achieved through consensus and distributed to the large community. We are very excited to be able to offer such a service to the community via the COSPAR Panel on Planetary Protection.”

Along with serving as Chair of the COSPAR PPP, Dr. Coustenis has extensive research experience regarding planetary surfaces and atmospheres, specifically outer solar system objects like Europa, Ganymede, Titan, and Enceladus, as these worlds are targets for future astrobiology research. Additionally, Dr. Coustenis’ research extends far beyond the solar system as she has helped distinguish and characterize exoplanetary atmospheres, as well. Regarding planetary protection, some notable publications include being a co-author on a March 2024 paper discussing planetary protection for a future crewed Mars mission and a 2023 paper discussing COSPAR requirements for exploring Venus. Given her knowledge and experience regarding planetary protection, what are some of the most exciting aspects about planetary protection that Dr. Coustenis has encountered during her career?

Dr. Coustenis tells Universe Today, “We have recently worked on the Moon exploration requirements to preserve the poles and the regions where liquid water could be found at some periods of time and are currently working on the missions that will explore icy worlds, like the moons of our giant planets that harbor liquid water oceans underneath their surfaces, as well as organic chemistry and energy sources. These could be habitable environments that we need to explore with care.”

As noted in the Acta Astronautica paper, the field of planetary protection requires international collaboration not only from a multitude of scientists, but also engineers, as they are the individuals responsible for building the spacecraft that are sent to far-off worlds for scientific exploration. Other disciplines that contribute to planetary protection include geology, physics, geophysics, biotechnology, astrobiology, biomedical, planetary science. It is through this constant collaboration of scientists, engineers, and medical professionals that planetary protection has successfully prevented contamination of planetary bodies outside the Earth, but also preventing contamination of the Earth from returned samples. Therefore, what advice can Dr. Coustenis offer to upcoming students who wish to pursue a career in planetary protection?

Dr. Coustenis tells Universe Today, “Planetary protection offers the possibility to contribute coming from many different fields, scientific, engineering, economic or legal. We need all these varied points of view in order to accomplish adequate characterizations of space missions and related requirements and also to establish the real value of planetary protection, the enabling capacity of this tool and to spread the word about what we do and how others can contribute, in particular the younger generations. So, we encourage students and early-career space aficionados to join COSPAR and learn more about our work and that of other commissions and panels within its structure so as to be able also to position themselves and engage with the space community.”

How will planetary protection teach us about our place in the cosmos in the coming years and decades? Only time will tell, and this is why we science!

As always, keep doing science & keep looking up!

The post Planetary Protection: Why study it? What can it teach us about finding life beyond Earth? appeared first on Universe Today.



New Telescope Images of Io are so Good, it Looks like a Spacecraft Took Them

The Large Binocular Telescope (LBT), located on Mount Graham in Arizona and run by the University of Arizona, is part of the next generation of extremely large telescopes (ELTs). With two primary mirrors measuring 8.4 m (~27.5 ft), it has a collecting area slightly greater than that of a 30-meter (98.4 ft) telescope. With their resolution, adaptive optics, and sophisticated instruments, these telescopes are expected to probe deeper into the Universe and provide stunning images of everything from distant galaxies to objects in our Solar System.

An international team led by the University of Arizona recently acquired images of Jupiter’s moon Io that were the highest-resolution pictures ever taken by a ground-based telescope. The images revealed surface features measuring just 80 km (50 mi) across, a spatial resolution previously reserved for spacecraft. This includes NASA’s Juno mission, which has captured some of the most stunning images of Io’s volcanoes. These images were made possible by the LBT’s new SHARK-VIS instrument and the telescope’s adaptive optics system.

The team was led by Al Conrad, an Associate Staff Scientist with the University of Arizona’s Department of Astronomy, the Stewart Observatory, and the Large Binocular Telescope Observatory (LBTO). He was joined by researchers from the University of California, Berkeley, the California Institute of Technology, and NASA’s Jet Propulsion Laboratory. Their paper, “Observation of Io’s Resurfacing via Plume Deposition Using Ground-Based Adaptive Optics at Visible Wavelengths With LBT SHARK-VIS (GRL),” and the LBT images are set to be published in the Geophysical Research Letters.

The Large Binocular Telescope, showing the two imaging mirrors. Credit: NASA

SHARK-VIS is a high-contrast optical coronagraphic imaging instrument designed and built at INAF-Osservatorio Astronomico di Roma. The instrument is fed by the refurbished LBT extreme Adaptive Optics system, called the Single conjugated adaptive Optics Upgrade for LBT (SOUL). It was installed in 2023 on the LBT along with the near-infrared instrument, SHARK-NIR, to take advantage of the telescope’s outstanding adaptive optics system. The key to the instrument is its fast, ultra-low-noise “fast imaging” camera that captures slow-motion footage that freezes the optical distortions caused by atmospheric interference.

Gianluca Li Causi, the data processing manager for SHARK-VIS at the Italian National Institute for Astrophysics, explained how it works in a recent University of Arizona News release:

“We process our data on the computer to remove any trace of the sensor’s electronic footprint. We then select the best frames and combine them using a highly efficient software package called Kraken, developed by our colleagues Douglas Hope and Stuart Jefferies from Georgia State University. Kraken allows us to remove atmospheric effects, revealing Io in incredible sharpness.”

The SHARK-VIS image was so rich in detail that it allowed the researchers to identify a major resurfacing event around Pele, one of Io’s largest volcanoes located in the southern hemisphere near the equator (and named after the Hawaiin deity associated with fire and volcanoes). The image shows a plume deposit around Pele covered by eruption deposits from Pillan Patera, a neighboring volcano. NASA’s Galileo spacecraft observed a similar eruption sequence while exploring the Jupiter system between 1995 and 2003. However, this was the first time an Earth-based observatory took such detailed images.

An artist's concept of the interior of Io. By Kelvinsong - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=31526383
An artist’s concept of the interior of Io. Credit: Kelvinsong/Wikimedia

“We interpret the changes as dark lava deposits and white sulfur dioxide deposits originating from an eruption at Pillan Patera, which partially cover Pele’s red, sulfur-rich plume deposit,” said co-author Ashley Davies, a principal scientist at NASA’s Jet Propulsion Laboratory. “Before SHARK-VIS, such resurfacing events were impossible to observe from Earth.” Io is the innermost of Jupiter’s largest moons (aka. Galilean moons), which include Europa, Ganymede, and Callisto. Since NASA’s Voyager 1 spacecraft flew through the Jupiter system in 1979, scientists have been fascinated by Io and its volcanic features.

Along with Europa and Ganymede, Io is locked in a 1:2:4 orbital resonance, where Europa makes two orbits for every orbit made by Ganymede, and Io makes four. Between its interaction with these moons and Jupiter’s powerful gravity, Io’s interior is constantly flexing, producing hot lava that erupts through the surface. While telescopes have taken infrared images that revealed hot spots caused by eruptions, they are not sharp enough to reveal surface details or identify the locations of the eruptions. By monitoring the eruptions on Io’s surface, scientists hope to gain insights into the tidal heating mechanism responsible for Io’s intense volcanism.

“Io, therefore, presents a unique opportunity to learn about the mighty eruptions that helped shape the surfaces of the Earth and the moon in their distant pasts,” said Conrad. Studies like this one, he added, will help researchers understand why some planets have active volcanoes while others do not. For instance, while Venus is thought to still be volcanically active, Mars is home to the largest volcanoes in the Solar System but is inactive. These studies may also shed light on volcanic exoplanets someday, helping astronomers to identify geological activity on distant planets (a possible indication of habitability).

SHARK-VIS instrument scientist Simone Antoniucci anticipates that it will enable new observations of objects throughout the Solar System with similar sharpness, revealing all manner of features that would otherwise require spacecraft.”The keen vision of SHARK-VIS is particularly suited to observing the surfaces of many solar system bodies, not only the moons of giant planets but also asteroids,” he said. “We have already observed some of those, with the data currently being analyzed, and are planning to observe more.”

Further Reading: University of Arizona

The post New Telescope Images of Io are so Good, it Looks like a Spacecraft Took Them appeared first on Universe Today.



South Korea is Planning to Send a Mission to Mars by 2045

It is truly wonderful to see so many nations aspiring to space exploration and trips to the Moon. Earlier this week on the 27th May, South Korea innaugurated its new space agency, the Korea AeroSpace Administration otherwise known as KASA. The group is headed up by former professor of aerospace engineering Yoon Young-bin. Whilst the group has yet to announce detailed plans for their upcoming missions Young-bin has stated they hope to land on the Moon by 2032 and to get to Mars by 2045.

The President of Korea, Yoon Suk-yeol, had confirmed that the government was committed to the space sector. To that end, they intend to secure investments of billions of dollars to fund the project. In March this year Korean Space Agency was formed in a ceremony that took place in March this year. Suk-yeol pleduged to facilitate 1,000 space companies and he hoped that 10 of the companies would become top-tier space firms. They would work hard to increase Korea’s share of the space market, aiming to hit 10% instead of the existing 1%. and create over 100,000 jobs. 

The Korean goverment has for sometime been keen to expand the space industry, Young-bin also prioritised support for the private sector. “The establishment of KASA will be an important stepping stone that guides the way for Korea to become a powerhouse in space economy by setting up the private-led space ecosystem,” Young-bin said. 

Young-bin is no stranger to space exploration since he had been researching space propulsion at the time of his appointment. His research chiefly focuses on liquid rocket engine. He has also been a serving director of the Institute of Advanced Aerospace Technology. 

Mid to long term goals and visions for space development are important next steps along the journey. To achieve those, KASA are striving for active cooperation from public, private and academic sectors. All of this is of course subject to securing the necessary funding. 

The framework for operations of KASA have been established and will be implemented with a maximum of 293 employees. Currenly only 110 are in place which includes a number of officials who were originally part of the Science Ministry in Korea. With the establishment of KASA, the Ministry of Science and ICT have been reorganised to align to their reduced scope of work but to find the remaining employees KASA will continue to search at home and abroad for the right people.

Along with their plans to explore the Moon and Mars, KASA is also planning to explore the Lagrangian Point known as L4. These regions in space lie along the Earth’s orbit and usually a little ahead or a litle behind but at these points, the gravitational force of the Earth and that of the Sun balance out against each other making for a highly efficient location for a probe. No country has acehived this yet so it will really put KASA on the international space exploration map.

They also plan to restore the Apophis mission which had been scrapped some years ago. The asteroid will pass close by Earth in 2029. The plan is for this to become an international mission, calling upon international co-operation. Other projects include participation in the Event Horizon Telescope and black hole imaging from one of NASA’s solar coronagraph.

Source : Korea ushers in new space era with KASA launch

The post South Korea is Planning to Send a Mission to Mars by 2045 appeared first on Universe Today.



Thursday, May 30, 2024

Io Has Been Volcanically Active for its Entire History

Jupiter’s moon Io is a volcanic powerhouse. It’s the most geologically active world in the Solar System, sporting more than 400 spouting volcanoes and vents on its surface. Has it always been this way? A team of planetary scientists says yes, and they have the chemical receipts to prove it.

In a recent paper, the team headed by CalTech scientist Katherine de Kleer cites data from millimeter observations of elemental isotopes found in Io’s eruptions. They found that chemicals like chlorine and sulfur exist in higher quantities at Io than in comparable places in the Solar System. Analysis shows that Io hasn’t just started erupting lately—it’s been going on for most of its history. And, it’s so volcanic that it practically resurfaces itself every million years or so.

The discovery of volcanism on Io was one of the major results of the Voyager mission. As the two spacecraft swept past Jupiter in 1979, their images revealed Io’s volcanic features and plumes. Since that time, the Galileo, Cassini-Huygens, New Horizons, and Juno missions also sent images. The Jovian system and its moons are also frequent targets for ground- and space-based observatories, including Hubble Space Telescope and JWST.

Facts about Io

Io is the fourth-largest Jovian moon and is one of the four Galilean satellites. It orbits closest to Jupiter and gets pulled by a gravitational tug-of-war between Jupiter and the other Galilean moons. The result is a process called “tidal heating” deep inside Io, produced by friction. That generates heat, which melts Io’s interior, and opens up vents so that the heat and melted material can escape to the surface.

An artist's concept of the interior of Io. By Kelvinsong - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=31526383
An artist’s concept of the interior of Io. By Kelvinsong – Own work, CC BY-SA 3.0, https://ift.tt/gEtYL0F

This little moon is mostly silicate rock atop an iron or iron sulfide core. The surface is scarred with volcanoes and deformed by compressional forces beneath the crust. The most obvious features are the volcanic mountains, plumes, and lava flows. Currently, Io’s volcanoes resurface the landscape at a rate of about 0.1 to 1.0 cm per year. They also paint its surface in an amazing array of colors. During the Voyager 2 flyby, people often compared its appearance to a pizza. The colors come mainly from sulfur and sulfurous compounds deposited across the landscape.

Normally, geologists would look at its surface and count craters to get an idea of its age. But, since volcanic flows erase craters, there’s no easy visual way to determine how long volcanic features have been around. However, it turns out that abundances of certain isotopes of sulfur and other elements could provide a good record the history of volcanism on Io.

Analyzing Io’s Chemistry

Io has probably lost mass to space throughout its history. de Kleer and her colleagues point out that its supply of volatile elements should be highly enriched in heavy stable isotopes. That’s because atmospheric escape processes generally favor the loss of lighter isotopes. They suggest that stable isotope measurements of volatile elements, such as sulfur and chlorine, could give accurate details about the history of volcanism at Io. So, it makes sense, then, to do a thorough chemical analysis of Io’s volcanic emissions now and extrapolate back.

Understanding Io’s current chemistry, requires, among other things, a good idea of its mass-loss history. Io’s mass loss occurs because of collisions between atmospheric molecules and energetic particles trapped in Jupiter’s magnetosphere. If this continued over Io’s history, then its chemistry should provide evidence of the volcanic past. In their paper, the team discusses the assumptions they made, including estimates of Io’s initial inventory of sulfur, as well as possible early mass-loss rates that could affect its current abundances of sulfur and chlorine—two elements that help determine past and present volcanism.

To get that history, team used the Atacama Large Millimeter Array to observe gases in Io’s atmosphere. The goal was to measure SO2, SO, NaCl, and KCl in various forms and determine the ratios of 34S to 32S and 37Cl to 35Cl. After analyzing the data, the team found that Io has lost at least 94 to 99 percent of its available sulfur over time. In addition, the measurements show enriched levels of chlorine. This probably indicates that Io has been volcanically active throughout time. It’s also possible that this tiny moon has experienced higher rates of outgassing and mass loss early in its history. More measurements should help scientists constrain Io’s volcanic activity even more tightly.

For More Information

Isotopic Evidence of Long-lived Volcanism on Io
Violent Volcanoes Have Wracked Jupiter’s Moon Io for Billions of Years

The post Io Has Been Volcanically Active for its Entire History appeared first on Universe Today.



Webb Finds the Farthest Galaxy Ever Seen (So Far)

There are some things that never cease to amaze me and the discovery of distant objects is one of them. The James Webb Space Telescope has just found the most distant galaxy ever observed! It has the catchy title JADES-GS-z14-0 and it has a redshift of 14.32. This means its light left when the Universe was only 290 million years old! That means the light left the source LOOOONG before even our Milky Way was here! How amazing is that!

The James Webb Space Telescope (JWST) with its 6.5m mirror was launched on 25 December 2021 and has quickly proven itself to be the most powerful space telescope ever built. It was designed to explore the Universe in visible and infrared radiation so that it could probe straight through dust to reveal hidden details behind. It is positioned at the second Lagrange point where the gravity of the Earth is balanced by the gravity of the Sun and it maintains a stable 1.5 million km from Earth. 

Artist impression of the James Webb Space Telescope

Over the last couple of years, astronomers have been using JWST to study the Cosmic Dawn! This period of time existed just a few hundred million years after the big bang but studying galaxies so far back in time required the sensitivity of the JWST. They provide valuable information about the gas and stars within and help to understand their formation. 

An international team were using JWST data that had been collected as part of the Advanced Deep Extragalactic Survey (JADES) using the Near-Infrared Spectrograph known as NIRSpec. They were able to acquire a spectrum of the galaxy revealing a redshift of 14.32. The redshift phenomenon occurs when the light from distant objects in space shift toward the red end of the spectrum. It was originally thought this was due to the movement but instead it is caused by the expansion of space. The greater the redshift, the faster the object is moving away and therefore the further away it is. 

The redshift of JADES-GS-z14-0 makes it the most distant galaxy known and it corresponds to the light having been emitted at a time when the Universe was just under 300 million years old. The team estimate the galaxy to be just over 1,600 light years across, that’s in comparison to the Milky Way which is thought to be 100,000 light years across. It is fairly typical of distant, early galaxies to be bright due to gas falling into a supermassive black hole but in the case of JADES-GS-z14-0 the light seems to be created by hot young stars. 

The image that has been released shows a field of thousands of distant galaxies of all manner of shapes, colours and sizes. One solitary bright star is visible in the foreground with the trademark diffraction spikes caused by the JWST optics. A box just to the lower right of centre highlights the location with the zoomed in image of the galaxy superimposed. The galaxy looks very different from those we tend to see in today’s Universe as it appears far less structured. 

Source : Webb finds most distant known galaxy

The post Webb Finds the Farthest Galaxy Ever Seen (So Far) appeared first on Universe Today.



Where are All the Primordial Black Holes?

The earliest black holes in the Universe called primordial black holes (PBHs), are strong contenders to help explain why the Universe is heavier than it looks. There’s only one problem: these miniature monsters haven’t exactly been observed—yet. But, when astronomers do find them, they might turn out to be part of the Universe’s dark matter component.

Primordial black holes are one of several types of highly massive objects thought to exist in the Universe. We already know about stellar-mass black holes. They form during the deaths of hugely massive stars and generally end up containing up to dozens of solar masses. Then there are the supermassive black holes, embedded in the hearts of most galaxies. They sequester up to millions of solar masses.

The intermediate-mass black holes occupy the middle of the “black hole” spectrum. They’re another hot topic in black hole research circles. Appropriately enough, the masses of these black holes are between their stellar and supermassive counterparts. All these types of massive objects can collide with each other to grow bigger black holes. That generates gravitational waves that can be detected. The “ping” of each gravitational wave tells scientists a great deal about the objects colliding, including their masses.

How we might discover primordial black holes and help solve the dark matter mystery. Credit: ESA
How we might discover primordial black holes and help solve the dark matter mystery. Credit: ESA

Understanding Primordial Black Holes in Context of Cosmic History

While astronomers search for PHBs, others are looking to explain why they might be part of the dark matter component of the Universe. In addition, they could explain the origin of binary black holes detected in gravitational wave observations.

A team of researchers at the University of Tokyo examined the “problem” of PBHs. Their work suggests that there should be far fewer of these objects than current models show. But, nobody knows how many existed back then. So, astronomers search them out using gravitational wave observatories. Their discovery should open a window on conditions in the early Universe when PBH formed.

These miniature ones are fascinating to think about. “Many researchers feel they are a strong candidate for dark matter, but there would need to be plenty of them to satisfy that theory,” said graduate student and team member Jason Kristiano. “They are interesting for other reasons too, as since the recent innovation of gravitational wave astronomy, there have been discoveries of binary black hole mergers, which can be explained if PBHs exist in large numbers. But despite these strong reasons for their expected abundance, we have not seen any directly, and now we have a model which should explain why this is the case.”

Modeling the Existence of Primordial Black Holes

The big question about PHBs: do (or did) they exist? And, can they be part of the dark matter component of the Universe? To answer that, Kristiano and his advisor Jun’ichi Yokoyama, searched through models of PBH formation. The best ones do not agree with the observed conditions of the leftover light fingerprint of the Big Bang. That’s called the cosmic microwave background (CMB). This is important, since PBHs formed in very early epochs of cosmic history, soon after the Big Bang. So, the team used the best model of PBH formation and applied quantum field theory to bring the model into alignment with reality.

Yokoyama explained the background behind their work. “At the beginning, the universe was incredibly small, much smaller than the size of a single atom. Cosmic inflation rapidly expanded that by 25 orders of magnitude. At that time, waves traveling through this tiny space could have had relatively large amplitudes but very short wavelengths. What we have found is that these tiny but strong waves can translate to otherwise inexplicable amplification of much longer waves we see in the present CMB,” said Yokoyama.

“We believe this is due to occasional instances of coherence between these early short waves, which can be explained using quantum field theory, the most robust theory we have to describe everyday phenomena such as photons or electrons. While individual short waves would be relatively powerless, coherent groups would have the power to reshape waves much larger than themselves. This is a rare instance of where a theory of something at one extreme scale seems to explain something at the opposite end of the scale.”

From Fluctuations to Miniature Black Holes

Those early small-scale fluctuations Yokohama describes affect some of the larger-scale fluctuations in the cosmic microwave background. Researchers can use measurements of wavelengths in the CMB to constrain the extent of corresponding wavelengths in the early Universe. That also puts some limits on any other phenomena that rely on the shorter, stronger wavelengths. And this is where the PBHs come back in.

“It is widely believed that the collapse of short but strong wavelengths in the early universe is what creates primordial black holes,” said Kristiano. “Our study suggests there should be far fewer PBHs than would be needed if they are indeed a strong candidate for dark matter or gravitational wave events.”

The next step relies on gravitational wave observatories and other types of observations. LIGO in the U.S., Virgo in Italy and KAGRA in Japan, are cooperating in observations aimed at finding the first PHBs. The results should help refine the ideas from Yokoyama’s team about PHBs and dark matter.

For More Information

The Case of the Missing Black Holes
Constraining Primordial Black Hole Formation from Single-Field Inflation
Note on the Bispectrum and One-loop corrections in Single-field Inflation with Primordial Black Hole Formation

The post Where are All the Primordial Black Holes? appeared first on Universe Today.



Wednesday, May 29, 2024

What’s Under This Hole on the Surface of Mars?

Human visitors to Mars need somewhere to shelter from the radiation, temperature swings, and dust storms that plague the planet. If the planet is anything like Earth or the Moon, it may have large underground lava tubes that could house shelters. Collapsed sections of lava tubes, called skylights, could provide access to these subterranean refuges.

Does this hole on Mars lead to a larger underground cavern?

This image was captured by the High-Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter (MRO). The pit is only a few meters across and is in the Arsia Mons region of Mars. Arsia Mons is one of the three dormant volcanos in the Tharsis Montes group of three volcanos.

This colourized image of the surface of Mars was created with data from the Mars Reconnaissance Orbiter. The line of three volcanoes is the Tharsis Montes, with Olympus Mons to the northwest and Valles Marineris to the east. Arsia Mons is the southernmost volcano of the three that comprise Tharsis Montes. Image: NASA/JPL-Caltech/ Arizona State University
This colourized image of the surface of Mars was created with data from the Mars Reconnaissance Orbiter. The line of three volcanoes is Tharsis Montes, with Olympus Mons to the northwest and Valles Marineris to the east. Arsia Mons is the southernmost volcano of the three that comprise Tharsis Montes. Image: NASA/JPL-Caltech/ Arizona State University

The Tharsis Region of Tharsis Bulge is a vast volcanic plain that’s thousands of kilometres across. It’s elevated compared to the rest of Mars and averages about 10km (33,000 ft) above the planet’s mean elevation. The region was volcanically active in the past, obviously, and features like the pit are a direct result of ancient volcanic activity.

Several pits in the Arsia Mons region may be collapsed skylights or openings into subterranean lava tubes. However, there is much uncertainty. An image of one of them shows an illuminated sidewall, which could indicate that it’s just a cylindrical pit.

These images of a pit near Arsia Mons were captured several years ago. The image on the left was captured first, and scientists wondered if it could lead to a lava tube or cave. Then, the image on the right, showing a side wall, was captured. The side wall could indicate that there's no tube or cave. Image Credit: NASA/JPL/University of Arizona
These images of a pit near Arsia Mons were captured several years ago. The image on the left was captured first, and scientists wondered if it could lead to a lava tube or cave. Then, the image on the right, showing a side wall, was captured. The side wall could indicate that there’s no tube or cave. Image Credit: NASA/JPL/University of Arizona

The hole in the featured image could be only a pit or shaft and not an entrance to a cave or lava tube. They’re found on Hawaiian volcanos, where they’re called pit craters. They don’t connect to long caves or lava tubes. They’re the result of a collapse that happened much deeper underground.

These four sequential images show how pit craters form. As volcanos erupt and settle, cracks form. They slowly migrate upwards, and rocks above them start to fall into them. Eventually, the upward migrating crack reaches the surface, and the roof caves in. On Earth, plants will eventually colonize the crater. On Mars, they stay much the same as when they collapsed. Image Credit: US National Park Service.
These four sequential images show how pit craters form. As volcanos erupt and settle, cracks form. They slowly migrate upwards, and rocks above them start to fall into them. Eventually, the upward migrating crack reaches the surface, and the roof caves in. On Earth, plants will eventually colonize the crater. On Mars, they stay much the same as when they collapsed. Image Credit: US National Park Service.

In Hawaii, the pit craters range from 6 to 186 m (20 to 610 feet) deep and from 8 to 1140 m (26 to 3,740 feet) wide. The Arsia Mons pit in the leading image is only about 178 m (584 feet) deep.

We have a much better understanding of lava pits and tubes on the Moon than we do on Mars. We know some of them are thermally stable at about 17 C (63 F.) We also have better images of them, with intriguing glimpses of boulder-covered floors.

Spectacular high Sun view of the Mare Tranquillitatis pit crater revealing boulders on an otherwise smooth floor. The 100-meter pit may provide access to a lunar lava tube. Image Credit: By NASA/GSFC/Arizona State University - http://photojournal.jpl.nasa.gov/catalog/PIA13518, Public Domain, https://commons.wikimedia.org/w/index.php?curid=54853313
Spectacular high Sun view of the Mare Tranquillitatis pit crater revealing boulders on an otherwise smooth floor. The 100-meter pit may provide access to a lunar lava tube. Image Credit: By NASA/GSFC/Arizona State University – https://ift.tt/rBwnm7i, Public Domain, https://ift.tt/oancdvQ

Lots of thinking is going into how to explore these lunar caves and lava tubes, including conceptual designs for robots that could explore them. Maybe on the Moon, astronauts could take shelter in inflatable habitats inside these tubes, where they’re protected from temperature swings, radiation, and micrometeorites.

But Mars is another question. There’s no reason that lava tubes shouldn’t exist on Mars. In fact, Mars’ gravity is much weaker than Earth’s, and that should allow for much larger tubes. Images of Mars show rilles, which are collapsed tubes. It seems likely that not all of these tubes have collapsed to form rilles.

One pit on the Martian volcano, Pavis Mons, is particularly intriguing. There’s some kind of void under the pit, but the nature of the pit is difficult to ascertain. Is it a lava tube? If it is, it dwarfs most tubes on Earth.

Martian lava tubes are still a mystery. Scientists have found plenty of morphological evidence suggesting that they’re plentiful. But in science, you can’t assume they’re there, even though it seems likely that they are. There’s no clear reason why they wouldn’t be. Could they one day provide shelter for astronauts? Maybe.

We need a robotic mission to explore them first.

The post What’s Under This Hole on the Surface of Mars? appeared first on Universe Today.



Sorry Spock, But “Vulcan” Isn’t a Planet After All

In 2018, astronomers detected an exoplanet around the star 40 Eridani. It’s about 16 light-years away in the constellation Eridanus. The discovery generated a wave of interest for a couple of reasons. Not only is it the closest Super-Earth around a star similar to our Sun, but the star system is the fictional home of Star Trek’s Vulcan science officer, Mr. Spock.

It’s always fun when a real science discovery lines up with science fiction.

Eridani’s other name is HD 26965, and it’s actually a triple-star system. Astronomers discovered the system’s lone planet, Eridani b, using the radial velocity method. Orbiting planets tug on their stars, and the star’s movement creates a change in its spectrum. Astronomical telescopes with spectrometers can detect the changes.

Jian Ge, an astronomy professor at the University of Florida, led the study that presented the discovery in 2018. At the time, Ge said in a press release, “The new planet is a ‘super-Earth’ orbiting the star HD 26965, which is only 16 light years from Earth, making it the closest super-Earth orbiting another Sun-like star. The planet is roughly twice the size of Earth and orbits its star with a 42-day period just inside the star’s optimal habitable zone.”

A super-Earth in the habitable zone around a Sun-similar star ‘only’ 16 light-years away is an intriguing discovery. Its link with a beloved Star Trek character gave the discovery wings, and word spread.

However, in the intervening years, follow-up observations have not confirmed Eridani b’s existence. A 2021 study suggested that the change in the star’s spectrum was a false positive. Now, a new study says that the exoplanet fondly named Vulcan does not exist.

The study is “The Death of Vulcan: NEID Reveals That the Planet Candidate Orbiting HD 26965 Is Stellar Activity.” It’s published in The Astronomical Journal, and the lead author is Abigail Burrows, an astronomer at Dartmouth College.

“We revisit the long-studied radial velocity (RV) target HD 26965 using recent observations from the NASA-NSF “NEID” precision Doppler facility,” Burrows and her co-authors write. After a deeper, line-by-line analysis of the radial velocity data, “… we demonstrate that the claimed 45-day signal previously identified as a planet candidate is most likely an activity-induced signal.”

Activity-induced signal means that the signal comes from the star’s activity, not from the external tug of an exoplanet.

Vulcan’s initial detection was based on data from the Dharma Planet Survey (DPS.) DPS monitored about 150 nearby Sun-like stars for changes in their spectra. Data from the Keck Telescope and the HARPS planet-finding spectrograph also contributed to the discovery.

When the planet was detected in 2018, the discoverers recommended caution. They presented the data as they collected it, along with their best interpretation. That’s standard in science, and they were careful in calling it a candidate planet. In their paper, they also discussed “the possibility that the RV signal is actually produced by stellar rotation modulated activity.” That activity could be sunspots, convection irregularities, or other things.

But in the end, they concluded that what they were seeing was likely a planet.

“By carefully examining the RV data in the active and quiet phases of the star, and after carefully considering all possible stellar activity sources, we concluded that the coherent signal seen from HD 26965 is most likely from a planet, with some RV noise contributed by stellar activity,” the authors wrote in the 2018 paper.

The rest of us were happy to agree because finding a super-Earth around a nearby Sun-like star is the kind of thing we hope to find.

“Men sometimes see exactly what they wish to see.”

-Spock of Vulcan

Sadly for Vulcan, the newest research shows that the stellar activity isn’t noise. It accounts for the entire signal.

The new results are based on NEID, the NN-explore Exoplanet Investigations with Doppler spectroscopy. It’s a high-resolution spectrometer attached to the WIYN (Wisconsin-Indiana-Yale-NOIRLab) telescope at Kitt Peak Observatory. The researchers used NEID to capture 63 spectra from Eridani over a six-month period.

NEID revealed a lot of information about the star, including things like contrast and radial velocity. Together, NEID data paints a more complete picture of the star and its activity. In this new work, Burrows and her co-researchers showed that all of this activity lines up with the star’s 42-day rotation period.

“All measurements show a strong signal at or near the 42-day stellar rotation period,” they write.

This figure from the study shows NEID data on the left. "All data show clear rotational modulation at or near the 42-day period," the authors write. The right shows periodograms for the data, which show "clear power at the stellar rotation period of ?42 days." Image Credit: Burrows et al. 2024
This figure from the study shows NEID data on the left. “All data show clear rotational modulation at or near the 42-day period,” the authors write. The right shows periodograms for the data, which show “clear power at the stellar rotation period of ?42 days.” Image Credit: Burrows et al. 2024

The authors write that their work “points toward a decaying starspot or plage” as the source of the signal. A plage is a bright spot on a star’s chromosphere. They used a variety of methods to reach this conclusion. “While each of these methods taken individually may not rule out a potential planetary signal at the same phase and period as the activity signal, collectively, our analyses show that an activity hypothesis is favoured over the specific planet claimed in Ma et al. (2018),” they conclude.

“When you eliminate the impossible, whatever remains, however improbable, must be the truth.”

Spock of Vulcan

The authors of the new paper didn’t set out to debunk Vulcan. Their paper is part of an effort to better understand the periodic and quasi-periodic spectral changes from Sun-like stars. Without a better understanding, annoying false positives will cloud our understanding of exoplanets, especially Earth-like ones around Sun-like stars. “To reach the precision necessary to detect temperate, Earth-mass extrasolar planets (exoplanets) around Sun-like stars using the radial velocity (RV) technique, the community must improve Doppler measurement precision significantly from the current state of the art,” they write.

“Detecting and characterizing these exo-Earths is vital for future spaceborne direct imaging missions, which will set the scientific priorities for the coming decade,” the authors explain.

The post Sorry Spock, But “Vulcan” Isn’t a Planet After All appeared first on Universe Today.



A Mini-Neptune in the Habitable Zone in a Binary Star System

Sometimes, it seems like habitable worlds can pop up almost anywhere in the universe. A recent paper from a team of citizen scientists led by researchers at the Flatiron Institute might have found an excellent candidate to look for one – on a moon orbiting a mini-Neptune orbiting a star that is also orbited by another star.

That’s a lot of things orbiting each other, so let’s dive into some details of the star system known as TOI 4633. It has two potential planets. One has a relatively short 34-day orbit but whose existence was only found by radial velocity measurements, as it doesn’t cross between the Earth and its host star. It also has yet to be confirmed by exoplanet hunters.

Another planet, known for now at TOI 4633c, is much more intriguing. It falls into the size category of a “mini-Neptune,” meaning it is slightly smaller than the 8th planet in our solar system but is likely still a gas giant with a thick atmosphere. It orbits its host star once every 272 days – making it one of the 40 longest-orbiting planets out of the thousands discovered so far.

Binaries are just one of a class of multiple-star systems, as Fraser explains.

That long orbit also puts it in the habitable zone of its host star – about .85 AU away from the G-type star it is orbiting. Being in the habitable zone would imply that liquid water could exist on its surface. However, the size of the planet and the likely density of its atmosphere would rule out the possibility of surface water on the planet itself.

However, there is a relatively good chance that TOI 4633c could have a moon. Planets with longer orbits tend to accrue them (hence why Venus and Mercury don’t have any in our own solar system). Such a small world wouldn’t have the same restrictive constraints as its gas-giant host planet, meaning it could potentially be habitable, such as the moons Pandora in the Avatar franchise or Endor in Star Wars.

But what makes this system even more unique is that the star TOI 4633c is orbiting is itself being orbited by another star. It wasn’t long ago that we weren’t even sure if planets could exist in these “binary” systems, and how strange life might be on one has become prominent recently with the popularity of The Three-Body Problem. But in theory, binary systems have habitable zones, and planets can survive in a stable orbit around at least one of the stars.

TESS’ primary mission is compete, but its data is still a treasure trove of new discoveries, as Fraser covers.

The smaller star orbits around its larger binary companion only once every 230 years and gets close enough to the other star to be considered relatively close by interstellar standards. As of now, it’s unclear what, if any, effect this proximity to another star would have on TOI 4633c, but it’s doubtful that it would be a world like Tatooine. 

However, the system lacks similarities to famous fictional examples, and it makes up for its potential to solve some long-standing problems in planetary formation theory. In addition to searching for a potential exomoon around TOI 4633c, scientists will continue to monitor the system closely to see if it remains stable. They can also see how the current known (and theorized) planets fit into existing models of planetary system formation.

This is another feather in the cap of the Planet Hunters TESS citizen science collaboration. There are undoubtedly more strange star systems out there for them to find. If you’re interested in helping them, you can sign up here.

Learn More:
NASA – Discovery Alert: Mini-Neptune in Double Star System is a Planetary Puzzle
Eisner et al. – Planet Hunters TESS. V. A Planetary System Around a Binary Star, Including a Mini-Neptune in the Habitable Zone
UT – Marvel at the Variety of Planets Found by TESS Already
UT – A New Venus-Sized World Found in the Habitable Zone of its Star

Lead Image:
Artist’s depiction of the binary system TOI 4633 and its potentially habitable planet.
Credit – Ed Bell for Simons Foundation

The post A Mini-Neptune in the Habitable Zone in a Binary Star System appeared first on Universe Today.



Astronomy Generates Mountains of Data. That’s Perfect for AI

Consumer-grade AI is finding its way into people’s daily lives with its ability to generate text and images and automate tasks. But astronomers need much more powerful, specialized AI. The vast amounts of observational data generated by modern telescopes and observatories defies astronomers’ efforts to extract all of its meaning.

A team of scientists is developing a new AI for astronomical data called AstroPT. They’ve presented it in a new paper titled “AstroPT: Scaling Large Observation Models for Astronomy.” The paper is available at arxiv.org, and the lead author is Michael J. Smith, a data scientist and astronomer from Aspia Space.

Astronomers are facing a growing deluge of data, which will expand enormously when the Vera Rubin Observatory (VRO) comes online in 2025. The VRO has the world’s largest camera, and each of its images could fill 1500 large-screen TVs. During its ten-year mission, the VRO will generate about 0.5 exabytes of data, which is about 50,000 times more data than is contained in the USA’s Library of Congress.

The VRO's need for multiple sites to handle all of its data is a testament to the enormous volume of data it will generate. Without effective AI, that data will be stuck in a bottleneck. Image Credit: NOIRLab.
The VRO’s need for multiple sites to handle all of its data is a testament to the enormous volume of data it will generate. Without effective AI, that data will be stuck in a bottleneck. Image Credit: NOIRLab.

Other telescopes with enormous mirrors are also approaching first light. The Giant Magellan Telescope, the Thirty Meter Telescope, and the European Extremely Large Telescope combined will generate an overwhelming amount of data.

Having data that can’t be processed is the same as not having the data at all. It’s basically inert and has no meaning until it’s processed somehow. “When you have too much data, and you don’t have the technology to process it, it’s like having no data,” said Cecilia Garraffo, a computational astrophysicist at the Harvard-Smithsonian Center for Astrophysics.

This is where AstroPT comes in.

AstroPT stands for Astro Pretrained Transformer, where a transformer is a particular type of AI. Transformers can change or transform an input sequence into an output sequence. AI needs to be trained, and AstroPT has been trained on 8.6 million 512 x 512-pixel images from the DESI Legacy Survey Data Release 8. DESI is the Dark Energy Spectroscopic Instrument. DESI studies the effect of Dark Energy by capturing the optical spectra from tens of millions of galaxies and quasars.

AstroPT and similar AI deal with ‘tokens.’ Tokens are visual elements in a larger image that contain meaning. By breaking images down into tokens, an AI can understand the larger meaning of an image. AstroPT can transform individual tokens into coherent output.

AstroPT has been trained on visual tokens. The idea is to teach the AI to predict the next token. The more thoroughly it’s been trained to do that, the better it will perform.

“We demonstrated that simple generative autoregressive models can learn scientifically useful information when pre-trained on the surrogate task of predicting the next 16 × 16 pixel patch in a sequence of galaxy image patches,” the authors write. In this scheme, each image patch is a token.

This image illustrates how the authors trained AstroPT to predict the next token in a 'spiralised' sequence of galaxy image patches. It shows the token feed order. "As the galaxies are in the centre of each postage stamp, this set up allows us to seamlessly pretrain and run inference on differently sized galaxy postage stamps," the authors explain. Image Credit: Smith et al. 2024.
This image illustrates how the authors trained AstroPT to predict the next token in a ‘spiralised’ sequence of galaxy image patches. It shows the token feed order. “As the galaxies are in the centre of each postage stamp, this set up allows us to seamlessly pretrain and run inference on differently sized galaxy postage stamps,” the authors explain. Image Credit: Smith et al. 2024.

One of the obstacles to training AI like AstroPT concerns what AI scientists call the ‘token crisis.’ To be effective, AI needs to be trained on a large number of quality tokens. In a 2023 paper, a separate team of researchers explained that a lack of tokens can limit the effectiveness of some AI, such as LLMs or Large Language Models. “State-of-the-art LLMs require vast amounts of internet-scale text data for pre-training,” the wrote. “Unfortunately, … the growth rate of high-quality text data on the internet is much
slower than the growth rate of data required by LLMs.”

AstroPT faces the same problem: a dearth of quality tokens to train on. Like other AI, it uses LOMs or Large Observation Models. The team says their results so far suggest that AstroPT can solve the token crisis by using data from observations. “This is a promising result that suggests that data taken from the observational sciences would complement data from other domains when used to pre-train a single multimodal LOM, and so points towards the use of observational data as one solution to the ‘token crisis’.”

AI developers are eager to find solutions to the token crisis and other AI challenges.

Without better AI, a data processing bottleneck will prevent astronomers and astrophysicists from making discoveries from the vast quantities of data that will soon arrive. Can AstroPT help?

The authors are hoping that it can, but it needs much more development. They say they’re open to collaborating with others to strengthen AstroPT. To aid that, they followed “current leading community models” as closely as possible. They call it an “open to all project.”

“We took these decisions in the belief that collaborative community development paves the fastest route towards realising an open source web-scale large observation model,” they write.

“We warmly invite potential collaborators to join us,” they conclude.

It’ll be interesting to see how AI developers will keep up with the vast amount of astronomical data coming our way.

The post Astronomy Generates Mountains of Data. That’s Perfect for AI appeared first on Universe Today.



Tuesday, May 28, 2024

The Sun’s Magnetic Field Might Only Be Skin Deep

It’s coming back! Sunspot AR3664 gave us an amazing display of northern lights in mid-May and it’s now rotating back into view. That means another great display if this sunspot continues to flare out. It’s all part of solar maximum—the peak of an 11-year cycle of solar active and quiet times. This cycle is the result of something inside the Sun—the solar dynamo. A team of scientists suggests that this big generator lies not far beneath the solar surface. It creates a magnetic field and spurs flares and sunspots.

For a long time, solar physicists thought the magnetic dynamo was deep inside the Sun. That view may change thanks to work by researchers at MIT, the University of Edinburgh, the University of Colorado, Bates College, Northwestern University, and the University of California. The dynamo may be related to instabilities in what’s called the “near-surface shear layer” in the Sun’s outermost regions. The activities in this layer result in the flares and sunspots we see more of as the Sun nears “solar maximum”. Flares are high-energy outbursts while sunspots are surface features with local magnetic fields. Sunspots are relatively cool regions on the solar surface and occur in 11-year cycles.

NASA’s Solar Dynamics Observatory captured these images of the solar flares — as seen in the bright flashes in the upper right — on May 5 and May 6, 2024. The image shows a subset of extreme ultraviolet light that highlights the extremely hot material in flares and which is colorized in teal. Credit: NASA/SDO
NASA’s Solar Dynamics Observatory captured these images of the solar flares — as seen in the bright flashes in the upper right — on May 5 and May 6, 2024. The image shows a subset of extreme ultraviolet light that highlights the extremely hot material in flares and which is colorized in teal. The loops are magnetic field lines channeling plasma. Credit: NASA/SDO

“The features we see when looking at the Sun, like the corona that many people saw during the recent solar eclipse, sunspots, and solar flares, are all associated with the sun’s magnetic field,” said MIT researcher Keaton Burns. “We show that isolated perturbations near the sun’s surface, far from the deeper layers, can grow over time to potentially produce the magnetic structures we see.”

How is the Sun’s Magnetic Field Connected to Activity?

To understand the magnitude of this finding, let’s look at the structure of the Sun. We all know the Sun is a superheated ball of plasma. So, how does boiling plasma create a magnetic dynamo? “One of the basic ideas for how to start a dynamo is that you need a region where there’s a lot of plasma moving past other plasma and that shearing motion converts kinetic energy into magnetic energy,” Burns explained. “People had thought that the Sun’s magnetic field is created by the motions at the very bottom of the convection zone.”

The interior structure of our Sun. The dynamo generating a magnetic field could lie very close to the solar surface. Credit: Kelvin Ma, via Wikipedia
The interior structure of our Sun. The dynamo generating a magnetic field could lie very close to the solar surface. Credit: Kelvin Ma, via Wikipedia

Of course, pinning down the exact location of the solar dynamo in the upper layers is difficult. Simulations can only go so far, and modeling the plasma flow throughout the entire Sun is a massive computing task. So, Burns and the team decided simulate a smaller piece of the Sun. They studied the stability of plasma flow near the solar surface. That required helioseismology data showing vibrations on the Sun’s surface, which allowed them to determine the average flow of plasma in that region. “If you take a video of a drum and watch how it vibrates in slow motion, you can work out the drumhead’s shape and stiffness from the vibrational modes,” said Burns. “Similarly, we can use vibrations that we see on the solar surface to infer the average structure on the inside.”

Think of the Sun as layered like an onion. Different plasma layers rush past each other as the Sun rotates, according to Burns. “Then we ask: Are there perturbations, or tiny changes in the flow of plasma, that we could superimpose on top of this average structure, that might grow to cause the sun’s magnetic field?”

Computing an Answer

The team developed algorithms that they incorporated into a numerical framework called the Dedalus Project. They looked for self-reinforcing changes in the Sun’s average surface flows. The algorithm discovered new patterns that could grow and result in realistic solar activity. Interestingly, those patterns also match the locations and timescales of sunspots. It turns out that certain changes in the flow of plasma at the very top of the Sun’s surface layers generate magnetic structures. This isn’t a new idea. Burns pointed out that the conditions there resembled the unstable plasma flows in accretion disks around black holes. Accretion disks are massive collections of gas and stellar dust that rotate in towards a black hole. They’re driven by “magnetorotational instability,” which generates turbulence in the flow and causes it to fall inward.

Burns and the team thought this phenomenon at a black hole might also be at work inside our Sun. They suggest that magnetorotational instability in the Sun’s outermost layers could be the first step in generating its magnetic field. “I think this result may be controversial,” he said. “Most of the community has been focused on finding dynamo action deep in the Sun. Now we’re showing there’s a different mechanism that seems to be a better match to observations.”

Implications of the New Model

Not only will the team’s work help solar physicists understand the creation of the magnetic dynamo, but may give them insight into other solar phenomena. In particular, a dynamo in the upper 10 percent of the Sun may explain things like the Maunder Minimum. This was a period between 1645 to 1715 when there were very few sunspots. In some years, observers saw no sunspots at all. In other years, they observed fewer than 20. Astronomers did chart the 11-year sunspot cycle through that time, so the Sun wasn’t entirely inactive.

If the Sun’s magnetic dynamo operates in its outermost layers, the science of solar activity forecasting could get a big boost. Right now, it’s difficult to tell when a flare might break out. Flares and coronal mass ejections like those that contributed to the May 10-11 geomagnetic storm can damage satellites and telecommunications systems here on Earth. In addition, power grids and other technology are at risk. In the long run, however, gaining new understanding of the Sun’s dynamo is a big deal.

“We know the dynamo acts like a giant clock with many complex interacting parts,” says co-author Geoffrey Vasil, a researcher at the University of Edinburgh. “But we don’t know many of the pieces or how they fit together. This new idea of how the solar dynamo starts is essential to understanding and predicting it.”

For More Information

The Origin of the Sun’s Magnetic Field Could Lie Close to Its Surface
The Solar Dynamo Begins Near the Surface

The post The Sun’s Magnetic Field Might Only Be Skin Deep appeared first on Universe Today.



Volcanoes Were Erupting on Venus in the 1990s

Start talking about Venus and immediately my mind goes to those images from the Venera space probes that visited Venus in the 1970’s. They revealed a world that had been scarred by millennia of volcanic activity yet as far as we could tell those volcanoes were dormant. That is, until just now.  Magellan has been mapping the surface of Venus and between 1990 and 1992 had mapped 98% of the surface. Researchers compared two scans of the same area and discovered that there were fresh outflows of molten rock filling a vent crater! There was active volcanism on Venus. 

Venus is the second planet from the Sun and similar in size to Earth, the similarities end there though. It has a thick atmosphere that is toxic to life as we know it, there is sulphuric acid rain high in the atmosphere and a surface temperature of almost 500 degrees. When the Venera probes visited they measured an atmospheric pressure of around 90 times that at the Earth’s surface. Combined with the other hostile properties of the atmosphere, a human visitor would not survive long. 

Venus

The dense atmosphere of Venus is largely the result of volcanic activity. Over the millennia, there have been extensive volcanic eruptions that pumped carbon dioxide into the atmosphere. The lack of bodies of water on Venus meant the built up carbon dioxide in the atmosphere didn’t get absorbed. In addition to this, the lack of a magnetic field meant the solar wind – the pressure from the Sun – drove away the lighter elements leaving behind the thick, carbon dioxide rich atmosphere we see today. But the volcanoes that drove the atmospheric changes are thought to have been extinct for a long time. 

It’s not just the Venera probes that have been exploring Venus. In 1980, the Magellan spacecraft was launched by NASA to map the surface of the hottest planet in the Solar System. On arrival, it was put into a polar orbit and used radar to penetrate the thick clouds. Back in 2023, a study of some of the Magellan images from the synthetic aperture radar showed changes to a vent near the summit of Maat Mons. It was the first direct evidence of an eruption on the surface of Venus and changes in the lava flows. 

The surface of Venus captured by a Soviet Venera probe. Credit: Russian Academy of Sciences / Ted Stryk

In the latest study that was published in Nature Astronomy, more data from the synthetic aperture radar was studied. The team focussed on Sif Mons and Niobe Planitia and the data that had been collected from both areas in 1990 and again in 1992. The data revealed stronger radar returns in the later set of data suggesting new rock formations from volcanic activity. The team did consider it may have been caused by some other phenomena such as sand dunes or atmospheric effects but altimeter data confirmed the presence of new solidified lava. 

The team were able to use lava flows on Earth as a comparison to help understand the new flows on Venus. They estimated that the new flows are between 3 and 20 metres deep. They could go a step further though and estimated that the eruption at Sif Mons produced about 30 square kilometres of rock which would be enough to fill over 36,000 swimming pools.  The eruption at Niobe Planitia produced even more with an estimated 45 square kilometres of rock..

Studying volcanic activity on Venus helps to understand not just the geological processes but also helps to understand the structure of the interior too. This can help inform the likelihood of habitability for future explorers. None of which would have been possible without the recent volcanic activity to help us probe further the secrets of Venus.

Source: Ongoing Venus Volcanic Activity Discovered With NASA’s Magellan Data

The post Volcanoes Were Erupting on Venus in the 1990s appeared first on Universe Today.



Enjoy Five New Images from the Euclid Mission

We’re fortunate to live in these times. Multiple space telescopes feed us a rich stream of astounding images that never seems to end. Each one is a portrait of some part of nature’s glory, enriched by the science behind it all. All we have to do is revel in the wonder.

The ESA’s Euclid space telescope is the latest one to enrich our inboxes. It was launched on July 1st, 2023, and delivered its first images in November of that year. Now, we have five new images from Euclid, as well as the first science results from the wide-angle space telescope.

“They give just a hint of what Euclid can do.”

Valeria Pettorino, ESA’s Euclid Project Scientist.

The images demonstrate the telescope’s power and its ability to address some of the deepest questions we have about the Universe. They are also impressive because of their visual richness and because they took only 24 hours of the telescope’s expected six years of observing time.

“Euclid is a unique, ground-breaking mission, and these are the first datasets to be made public – it’s an important milestone,” says Valeria Pettorino, ESA’s Euclid Project Scientist. “The images and associated science findings are impressively diverse in terms of the objects and distances observed. They include a variety of science applications, and yet represent a mere 24 hours of observations. They give just a hint of what Euclid can do. We are looking forward to six more years of data to come!”

The leading image is the most stunning and perhaps the most relatable. It shows Messier 78, aka NGC 2068. It’s a reflection nebula and star-forming region contained in the vast Orion B molecular cloud complex. Euclid used its infrared capabilities to see through the dust that shrouds the star-formation region. It’s given us our most detailed look at the filaments of gas and dust that give the region its ghostly appearance.

Euclid can detect objects that are just a few times more massive than Jupiter, an impressive feat. In its M78 image, it found over 300,000 objects in that mass range.

This zoomed-in portion of Euclid’s M78 image shows the depth the telescope’s images deliver. Image Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi. LICENCE CC BY-SA 3.0 IGO

One of Euclid’s objectives is to study dark matter and how it’s distributed in the Universe. It uses gravitational lensing to probe dark matter, and its image of the Abell 2390 galaxy cluster exhibits the tell-tale curved arcs of light coming from distant background objects created by gravitational lensing. The image also shows more than 50,000 galaxies.

Euclid's image of the Abell 2390 cluster of galaxies contains over 50,000 galaxies. It also shows the intracluster light that comes from individual stars torn from their galaxies and sitting in intergalactic space. These stars can help astrophysicists determine where dark matter is. Image Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi. LICENCE: CC BY-SA 3.0 IGO
Euclid’s image of the Abell 2390 cluster of galaxies contains over 50,000 galaxies. It also shows the intracluster light that comes from individual stars torn from their galaxies and sitting in intergalactic space. These stars can help astrophysicists determine where dark matter is. Image Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi.
LICENCE: CC BY-SA 3.0 IGO

Most of the stars currently forming in the Universe are forming in spiral galaxies. Euclid captured this image of NGC 6744 as an archetype of that galaxy type. The telescope’s wide-angle lens and depth of field capture the entire galaxy and also small details. It shows lanes of dust that emerge as spurs on the spiral arms.

With this image, astronomers can map individual stars and the gas that feeds their formation. They can also identify globular clusters and new dwarf galaxies. Euclid already found one new dwarf galaxy astronomers have never seen before, which is impressive for a galaxy that’s already been studied so intently.

Euclid's complete image of NGC 6744 is on the left, and a zoomed-in portion is on the right. NGC 6744 is one of the largest spiral galaxies outside our region of space. The telescope's detailed image will let astronomers count and map individual stars and map the gas that feeds star formation. Star formation is how galaxies evolve, so studying NGC 6744's star formation activity feeds into a greater understanding of galaxy evolution. Image Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi. LICENCE: CC BY-SA 3.0 IGO
Euclid’s complete image of NGC 6744 is on the left, and a zoomed-in portion is on the right. NGC 6744 is one of the largest spiral galaxies outside our region of space. The telescope’s detailed image will let astronomers count and map individual stars and the gas that feeds star formation. Star formation is how galaxies evolve, so studying NGC 6744’s star formation activity feeds into a greater understanding of galaxy evolution. Image Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi. LICENCE: CC BY-SA 3.0 IGO

Euclid also imaged another galaxy cluster, Abell 2764. This cluster contains hundreds of galaxies within a halo of dark matter. Euclid’s impressive wide-field view comes into play in this image. Not only does it show Abell 2764 in the image’s upper right, but it also shows other clusters that are even more distant, multiple background galaxies, and interacting galaxies with their streams of stars.

In this image, Euclid captured galaxy cluster Abell 2764 and the wider region surrounding it. Abell 2764 is in the upper right corner. Image Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi LICENCE CC BY-SA 3.0 IGO
In this image, Euclid captured galaxy cluster Abell 2764 and the wider region surrounding it. Abell 2764 is in the upper right corner. Image Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi LICENCE CC BY-SA 3.0 IGO

The image highlights one of Euclid’s other capabilities. The foreground star is in our own galaxy, and when viewed with a telescope, its diffuse light creates a halo that obscures distant objects behind it. Euclid was built to minimize that diffuse halo effect. The disturbance from the star’s diffuse light is minimal, meaning Euclid can see distant background objects near the star’s line of sight.

This pair of zoomed-in images of Abell 2764 shows Euclid's power. On the left is the foreground star. These stars can create halos of diffuse light that obscure other objects, but Euclid is built to minimize the effect. On the right is a zoom-in of Abell 2764 itself, with multitudes of background galaxies. Image Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi. LICENCE: CC BY-SA 3.0 IGO
This pair of zoomed-in images of Abell 2764 shows Euclid’s power. On the left is the foreground star. These stars can create halos of diffuse light that obscure other objects, but Euclid is built to minimize the effect. On the right is a zoom-in of Abell 2764 itself, with multitudes of background galaxies. Image Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi. LICENCE: CC BY-SA 3.0 IGO

The final of the five new images is of galaxies in the Dorado Group. Euclid’s image shows signs of galaxies merging. The Dorado Group is a relatively young group, and many of its member galaxies are still forming stars. The image helps astronomers study how galaxies form and evolve inside halos of dark matter.

The Dorado Group is one of the richest galaxy groups in the southern hemisphere. Euclid's wide and deep images give astronomers their best look at it. Image Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi. LICENCE: ESA Standard Licence
The Dorado Group is one of the richest galaxy groups in the southern hemisphere. Euclid’s wide and deep images give astronomers their best look at it. Image Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi. LICENCE: ESA Standard Licence

A zoomed-in image shows more detail of the main pair of galaxies in the image. Euclid’s unique large field-of-view and high spatial resolution means that for the first time, astronomers can use the same instrument and observations to deeply study tiny objects the size of star clusters, intermediate objects like the central regions of galaxies, and larger features like tidal tails in one large region of the sky.

“The beauty of Euclid is that it covers large regions of the sky in great detail and depth, and can capture a wide range of different objects all in the same image – from faint to bright, from distant to nearby, from the most massive of galaxy clusters to small planets.”

ESA Director of Science, Prof. Carole Mundell

Prior to Euclid, astronomers had to use small chunks of data to painstakingly catalogue globular clusters around galaxies. But Euclid’s wide images capture far more data in a single image, simplifying the task. Globular clusters provide important clues to how galaxies evolve over time.

This zoom-in shows a pair of interacting galaxies in the Dorado Group. Tidal tails of stars are visible as wispy streams near the right and bottom right of the right-side galaxy. Image Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi. LICENCE: ESA Standard Licence
This zoom-in shows a pair of interacting galaxies in the Dorado Group. Tidal tails of stars are visible as wispy streams near the right and bottom right of the right-side galaxy. Image Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi. LICENCE: ESA Standard Licence

Euclid’s mission is only starting. The telescope’s images so far have no equivalent, and there’s much more to come. Euclid hasn’t even begun its main survey yet. That survey will comprise both a wide survey covering about 15,000 square degrees of the sky and a deep survey covering about 50 square degrees.

“It’s no exaggeration to say that the results we’re seeing from Euclid are unprecedented,” says ESA Director of Science, Prof. Carole Mundell. “Euclid’s first images, published in November, clearly illustrated the telescope’s vast potential to explore the dark Universe, and this second batch is no different.”

“The beauty of Euclid is that it covers large regions of the sky in great detail and depth, and can capture a wide range of different objects all in the same image – from faint to bright, from distant to nearby, from the most massive of galaxy clusters to small planets,” said Mundell. “We get both a very detailed and very wide view all at once. This amazing versatility has resulted in numerous new science results that, when combined with the results from Euclid’s surveying over the coming years, will significantly alter our understanding of the Universe.”

The scientific papers released with these images are available here.

The post Enjoy Five New Images from the Euclid Mission appeared first on Universe Today.