The standard model of cosmology predicts that the Universe is homogeneous. A new study tests this using the polarization of the cosmic microwave background and finds this isn't quite true. This study supports an earlier study which also found a small polarization bias.
Galaxies are like snowflakes, no two exactly alike, even the spirals. The Hubble Space Telescope did a visual dive into the distant spiral NGC 4693 and found some intriguing hints to its past. For one thing, this member of the Virgo Cluster seems to have a central region that's rotating out of sync with the spiral arms and bulge. Those arms don't seem to connect to the central region, and the bulge itself seems to extend out above the plane of the galaxy.
SpaceX sent its Starship super-rocket on its first orbital flight — a shorter-than-planned test mission that put operational Starlink satellites into orbit for the first time.
Something deep inside Mars has scientists looking for clues to its internal evolution. A team at the University of Arizona led by Alexander Byrne, used a technique called "tidal tomography" to probe a heat anomaly in the southern hemisphere mantle. It turns out this subsurface region measures about 200 to 400 degrees Celsius warmer than the rest of the mantle. That warm spot may contain information about how Mars has changed over its lifetime.
Scientists love taking inspiration from nature. The evolutionary processes that have created such a diverse panoply of life on Earth can be a great source of ideas in solving technical problems. One such example is the pattern of sunflower seeds - they are arranged in a mathematically optimized pattern known as a Vogel spiral, and the international team building the Square Kilometer Array (SKA) in Australia decided to lay out their antennas in a similar pattern. But, as they report in a paper recently published in the Journal of Astronomical Telescopes, Instruments, and Systems, when they did so they found a huge blind spot in the data which hints that maybe this particular natural pattern might need to be modified to work well for this particular application.
As humanity continues to move towards a permanent settlement on the Moon, we still have at least one big hurdle to face - the lunar night, which lasts for roughly fourteen days straight and can drop temperatures to a bone-chilling -223°C. In order to survive those conditions, we need a power source that doesn’t come and go with the Sun, or rely on non-existent stock of coal, gas or wind. In other words, we need nuclear power, and a new paper, available in pre-print on arXiv by Julius Mercz of the Technical University of Munich and his co-authors, describes a new type of nuclear reactor that wouldn’t just power a habitat’s environmental systems, but also enable its materials extraction technologies as well.
The early stages of the solar system remain shrouded in mystery. Not much remains from that time, but scientists have developed plenty of theories about what was going on back then. One of those theories attempts to answer a simple question - did the early system prefer “fire” or “ice”? A new paper published in Nature Astrophysics from lead author Damanveer Grewal, an assistant professor of Earth and planetary sciences at Yale, and his co-authors, have a definitive answer to that question - the early solar system preferred fire.
