Posted on

Do The Gaps in Protoplanetary Disks Really Indicate Newly Forming Planets?

Modern instruments like ALMA have revealed newly forming stars surrounded by accretion disks. These images are so sensitive you can even see the gaps in the disk where new planets form, right? Maybe not. According to a new paper, systems with many newly forming planets are inherently unstable, so they can’t all indicate new worlds. Some gaps and rings around the stars might just indicate collections of pebbles that can never accrete into actual planets. The challenge will be to figure out which is which.

Posted on

An Improved Radioisotope Thermoelectric Generator Could Dramatically Reduce The Weight Of Interplanetary Missions

Radioisotope thermoelectric generators (RTGs) are the power plants of the interplanetary spacecraft. Or at least they have been for going on 50 years now. But they have significant drawbacks, the primary one being that they’re heavy. Even modern-day RTG designs run into the hundreds of kilograms, making them useful for large-scale missions like Perseverance but …

Continue reading “An Improved Radioisotope Thermoelectric Generator Could Dramatically Reduce The Weight Of Interplanetary Missions”

Posted on

We Could SCATTER CubeSats Around Uranus To Track How It Changes

Exploration missions to the outer solar system are still sorely lacking, even though they were highly prioritized in the Planetary Science Decadal Survey from 2013-2022. In fact, many planets in the outer solar system have never even been orbited by a probe. For one in particular – Uranus – we must rely on data from …

Continue reading “We Could SCATTER CubeSats Around Uranus To Track How It Changes”

Posted on

A Planet Was Swallowed by a Red Giant, But it Survived

When our Sun runs out of hydrogen fuel in its core, it’ll switch to burning helium and bloat up as a red giant. This will make it 100 times larger, gobbling up the inner planets and maybe even Earth. Maybe there’s hope. Astronomers have found a planet orbiting a dying star that must have been swallowed up during that expansion phase. The star would have been 1.5 times bigger during the red giant phase than the planet’s orbit. Being inside a red giant star doesn’t lead to the inevitable death of a planet.

Posted on

Planets Might Protect their Water Until their Star Settles Down

Creating rocky planets is a messy, dangerous, hot business. Planetesimals accrete together, which creates heat and pressure on the newborn world. The nearby adolescent star bombards them with intense radiation. That likely “bakes off” any surface oceans, lakes, or rivers, which is a disaster if you’re looking for places where life might arise or exist. …

Continue reading “Planets Might Protect their Water Until their Star Settles Down”

Posted on

Blue Straggler Stars are Weird

All stars follow a particular path in their lives once they start fusing hydrogen. As they live they steadily get brighter and hotter until they turn to fusing other elements. Every star follows this exact same path…except the blue straggler stars.

Posted on

A Star Came too Close to a Black Hole. It Didn’t End Well

Black holes are confounding objects that stretch physics to its limits. The most massive ones lurk in the centers of large galaxies like ours. They dominate the galactic center, and when a star gets too close, the black hole’s powerful gravitational force tears the star apart as they feed on it. Not even the most …

Continue reading “A Star Came too Close to a Black Hole. It Didn’t End Well”