Gaia Finds 12 Examples of Einstein Crosses; Galaxies Being Gravitationally Lensed so we see Them Repeated 4 Times

In 1915, Einstein put the finishing touches on his Theory of General Relativity (GR), a revolutionary new hypothesis that described gravity as a geometric property of space and time. This theory remains the accepted description of gravitation in modern physics and predicts that massive objects (like galaxies and galaxy clusters) bend the very fabric...

2h

Brown Dwarfs can Spin so Fast They Almost Tear Themselves Apart

We tend to image planets as spheres. Held together by gravity, the material of a planet compresses and shifts until gravity and pressure reach a balance point known as hydrostatic equilibrium. Hydrostatic equilibrium is one of the defining characteristics of a planet. If a planet were stationary and of uniform density, then at equilibrium, it would...

3h

OSIRIS-REx Did One Last Close Flyby of Asteroid Bennu. It’s Almost Time to Come Home

After more than two years in orbit around asteroid Bennu, NASA’s OSIRIS-REx spacecraft is ready to come home. It’s bringing with it a pristine sample of space rocks that geologists here on Earth are eager to study up close. The sample will arrive in September 2023, but we won’t have to wait nearly that long for new data from OSIRIS-REx. Last week, the...

5h

How’s the Weather in Jezero Crater? According to Perseverance: Cold

On February 18th, 2021, the Perseverance rover landed in the Jezero crater on Mars. Shortly thereafter, it powered up some of the scientific instruments it will use to conduct science operations and search for potential evidence of past life. One such instrument is the Mars Environmental Dynamics Analyzer (MEDA), which turned on for 30 minutes and issued...

22h

Primordial Asteroids That Never Suffered Massive Collisions all Seem to be Larger Than 100 km. Why?

Planetary systems form out of the remnant gas and dust of a primordial star. The material collapses into a protoplanetary disk around the young star, and the clumps that form within the disk eventually become planets, asteroids, or other bodies. Although we understand the big picture of planetary formation, we’ve yet to fully understand the details....

2d

What Would Raindrops be Like on Other Worlds?

Precipitation is much more widespread throughout that solar system than commonly assumed.  Obviously it rains water on Earth.  But it snows carbon dioxide on Mars, rains methane on Titan, sulfuric acid on Venus, and could potentially rain diamonds on Neptune.  The type of material falling out of the sky is almost as varied as the planets themselves. ...

2d

Jupiter Could Make an Ideal Dark Matter Detector

So, you want to find dark matter, but you don’t know where to look? A giant planet might be exactly the kind of particle detector you need! Luckily, our solar system just happens to have a couple of them available, and the biggest and closest is Jupiter. Researchers Rebecca Leane (Stanford) and Tim Linden (Stockholm) released a paper this week describing...

2d

Perseverance Takes a Selfie With Ingenuity. It’s Almost Time to fly

Perseverance is having a proud parent moment in this image, looking like it’s waiting with a child at the bus stop on the first day of school. The Mars 2020 rover took this selfie with the Ingenuity helicopter, which is preparing to take the first controlled flight ever on another world. On April 3rd, Ingenuity was removed from...

3d

What are the Best Ways to Search for Technosignatures?

The search for extraterrestrial intelligence (SETI) has long roots in human history.  With the advent of modern technologies, scientists were finally able to start scanning the skies for any sign of life.  When the search first started back in the 1960s, it focused almost exclusively on trying to detect radio signals.  Over the decades, no irrefutable...

3d

An Intermediate-Mass Black Hole Discovered Through the Gravitational Lensing of a Gamma-ray Burst

Black holes come in three sizes: small, medium, and large. Small black holes are of stellar mass. They form when a large star collapses at the end of its life. Large black holes lurk in the centers of galaxies and are millions or billions of solar masses. Middle-sized black holes are those between 100 to 100,000 solar masses. They are known as Intermediate...

4d