Astronomy

About 4.5 billion years ago, the most momentous event in the history of Earth occurred: a huge celestial body called Theia collided with the young Earth. How the collision unfolded and what exactly happened afterward has not been conclusively clarified. What is certain, however, is that the size, composition, and orbit of Earth changed as a result—and that the impact marked the birth of our constant companion in space, the moon.

The surface of the Earth is finite. We can measure it. If it was expanding, then its size would grow with time. And once again, good ol’ Earth helps us understand what the universe might be doing beyond our observable horizon.

Now outbound after its perihelion or closest approach to the Sun

Alnitak, Alnilam, Mintaka

Sometimes the dark dust of interstellar space has an angular elegance.

What does the Milky Way look like in radio waves?

What has happened to Comet Lemmon's tail?

If this is Saturn, where are the rings?

Seen to the left of Saturn's banded planetary disk, small icy moons

The 2015 Paris Agreement forged a path for the world to stave off the worst climate change scenarios. Here’s where we stand 10 years later

Material science plays a critical role in space exploration. So many of the challenges facing both crewed and non-crewed missions come down to factors like weight, thermal and radiation tolerance, and overall material stability. The results of a new study from Young-Kyeong Kim of the Korea Institute of Science and Technology and their colleagues should therefore be exciting for those material scientists who focus on radiation protection. After decades of trying, the authors were able to create a fully complete “sheet” of Boron Nitride Nanotubes (BNNTs).

Ethicists say AI-powered advances will threaten the autonomy of people who use neurotechnology

Scientists have achieved a breakthrough that seemed impossible just months ago, they have simulated our entire Milky Way galaxy down to each of its 100 billion individual stars. By combining artificial intelligence with supercomputer power, researchers created a model that captures everything from galactic arms to the explosive deaths of individual stars, completing in days what would have taken conventional simulations 36 years. This fusion of AI and physics represents a significant shift in how we model complex systems, with implications reaching far beyond astronomy.

Scientists from New York University Abu Dhabi (NYUAD) have uncovered new evidence that water once flowed beneath the surface of Mars, revealing that the planet may have remained habitable for life much longer than previously thought.

An expanding universe complicates this picture just a little bit, because the universe absolutely refuses to be straightforward.

I honestly don’t have a decent analogy for you to explain how the universe is expanding without a center and without an edge. It just does, whether we can wrap our minds around it or not. But I CAN give you a way to think about it.

Studies of insulin, blood sugar and diabetes in other animals such as fish and dogs have already saved millions of lives and could lead to new treatments for type 1 and type 2 diabetes.

Uranus is its closest to Earth all year on the night of November 21st, and you can find it easily in the evening sky using Sky & Telescope’s exclusive star chart.

The post Spot Uranus at Opposition appeared first on Sky & Telescope.

The decision to move Iran’s capital is partly driven by climate change, but experts say decades of human error and action are also to blame