The ASTRID cosmological simulation has run from the Universe's early days up to the present day, z=0. ASTRID is larger than some other simulations, and smaller than others. But with a higher number of particles, it has higher-resolution than its fellows. Among other things, this can tell astronomers where to look for gravitational waves from black hole mergers with future GW observatories.
Black holes are some of the most awe-inspiring and mysterious celestial objects in the universe. This is primarily because astronomers still don’t understand the underlying mechanisms that drive black holes, including its formation, evolution, and end. As their name implies, black holes can’t be viewed directly since they blend into the background of the vastness of space. Therefore, astronomers are limited to “seeing” black holes when they consume other celestial objects, most notably stars. When this happens, the astronomers see the light from the star being violently consumed by a nearby black hole in a spectacular display. However, astronomers are still puzzled regarding what happens after the consumption.
Scientists and philosophers have argued over the nature of time since … well, since time immemorial. Is time real, or is it a convenient illusion? Why does time seem to flow in just one direction? In a new book called “On Time,” British physicist Jim Al-Khalili lays out what he thinks is the answer to such questions.
Sure. It’s just another image of Phobos crossing the disk of the Sun, as seen from the surface of Mars. Like so much of the modern space era, these images, once amazing, are now almost routine. But there’s some real science behind tasking the Mars rovers to conduct a little ‘Martian astronomy.’
The planet Jupiter hosts more than 100 moons with the majority of attention going to the four Galilean moons, Io, Europa, Ganymede, and Callisto. This is primarily due to their active geology, including Io being the most volcanically active planetary body in the solar system and Europa having a vast subsurface liquid water ocean beneath its icy crust. However, Jupiter’s smaller and lesser-known moons could provide astronomers key insights into the history of the solar system since they’ve remained largely unchanged, unlike the Galilean moons.
When a meteoroid hits the Moon's surface, it does more than just dig up a little dirt. It actually excavates a little bit of cosmic history that recorded a long-ago supernova explosion. Scientists at the University of Hawaii Institute of Geophysics and Planetology have come up with a way to decode that history and learn something about such energetic events in the Universe.
NASA's newest eye on the sky, the Nancy Grace Roman Space Telescope, has begun its journey to unravel the secrets of dark matter, dark energy and Earthlike planets — months ahead of schedule.
