New Astrobites Post: Why are Sub-Neptunes so Abundant?

Here it is…my final new post for Astrobites…wow, how has it been two years?? What a wonderful ride it’s been. I’m so grateful for this collaboration – for the friendships and connections, for the writing experience, and for the chance to learn about astronomy in ways I might not have been able to.

This final post explores why sub-Neptune exoplanets seem to be so much more abundant than Neptune-like planets, despite being close in mass. It turns out that there are complex interactions between the gaseous envelope of these planets and their cores that weren’t being accounted for…but you’ll have to go read the post for the details!

The radius cliff for known exoplanets

New Astrobites Post: Measuring the Winds on Jupiter and Saturn Using Gravity

Here’s a new post for Astrobites!. The authors of today’s paper used gravity measurements from the NASA missions Juno and Cassini (orbiting Jupiter and Saturn, respectively) to calculate how deep winds penetrate into each planet. Read the full post to find out how they did it!

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The east-west (zonal) wind flows on Jupiter and Saturn, which align with the bands on each planet

New Astrobites Post: Chomospheric Cannonballs on the Sun

Here’s a new post for Astrobites!. This one covers a newly-discovered phenomenon on the Sun, playfully named “cannonballs.” The best part? They join other phenomena like “spicules,” “anemone jets,” and “Ellerman bombs” (which are also known as Severny moustaches)!

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From left to right: spicules, surges, and an Ellerman bomb. Credits from left to right: NASA, N. Nishizuka et al 2011 ApJ 731 43 Figure 3a, David Darling.

New Astrobites Post: The Boundary Between 'Icy' and 'Gassy' Giant Planets

Here’s my newest post for Astrobites!

Why does a planet form more like a Jupiter (lots of gas and very little ice) or more like a Neptune (less gas, and more ice)? Read on to find out!

New Astrobites Post: Measuring the Expanding Universe with Binary Black Holes

It’s been a minute, but I have another new post up on Astrobites!

This latest post describes how some talented colleagues of mine, Marcelle Soares-Santos and Antonella Palmese, led efforts to measure how fast the universe is expanding using the collision of two black holes measured by LIGO. This is an important measurement because this particular method is completely independent of other previous methods. Previous methods have relied on electromagnetic signals, such as from a specific type of supernova (Type Ia) or the Cosmic Microwave Background, but these methods are currently in tension with each other. Measuring the expansion rate of the universe using binary black holes will be able to tell us which, if either is right!

Unfortunately, the authors only had one event to work with, but they show that with 100 events, binary black hole collisions will be an equally powerful way to measure the expanding universe as current methods!

Simulation of a binary black hole merger. Credit: Simulating eXtreme Spacetimes project