Dr. Nora @norasguidetothegalaxy@qoto.org

Weekly #space / #astronomy news update!

○ InSight's fading power 😢
○ formation of DF2/DF4 (no dark matter!)
○ how soon will humans reach an asteroid?
○ Psyche mission delay
○ OFT-2 in the books! ✅
○ 👀 tau Herculids on May 30

➡️https://youtu.be/1gP9ZK7CYAo

Weekly #space / #astronomy news update!

○ Ingenuity was out...but it's back!
○ 1000+ new asteroids in Hubble data
○ OFT-2 Flight Readiness Review: ✅
○ 65 elements IDed in a star (a record!)
○ Event Horizon Telescope imaged Sagittarius A*!!!

https://youtu.be/stfbdL2ue6w

Could advanced alien species rearrange the planets in their systems to leave a lasting message of their existence?!?

...yeah, actually...

https://arxiv.org/abs/2204.14259

@nissyen yep! I do love my research but decided being a professor isn't a goal of mine. Aiming for science communication!

If this thread got you excited, you can also watch me talk about this research: https://youtu.be/0smzHsburh8?t=1847

Ty!! 😊

While in general the presence of the giant planets reduces the relative habitability compared to a system with just an exo-Earth, there are some cases where the giant planets make the system "ultra-habitable":

A couple trends we saw:

• Mass of the giant planets ↑, relative habitability ↓
• Very low relative habitability when the giant planets are in the habitable zone
• Eccentricity of the giant planets ↑, relative habitability ↓
• Secular resonances can have big effects

We looked at 147,456 different pairs of giant planets! This dataset is huge and 8-dimensional, so there's a LOT remaining to be found in it! You can play around with it yourself at: https://doi.org/10.5281/zenodo.6324216

For each giant planet pair, we consider 80 different locations of the exo-Earth. At each of these locations, we find the stability and habitability probabilities. Then we can integrate over the exo-Earth locations to find a relative habitability for the giant planet pair.

In general, as the exo-Earth's eccentricity increases, it gets more sunlight from its star, making it less habitable in the inner regions and more habitable in the outer regions.

My latest (and likely last!) paper is up on arXiv today! As the title says, it's about the "Relative Habitability of Exoplanet Systems with Two Giant Planets".

Go check it out ➡️ https://arxiv.org/abs/2205.02777

Or for a TL;DR, continue ⬇️

The basic idea is, given an exoplanet system with 2 giant planets, what can we say—from a dynamical perspective—about its ability to host a habitable Earth-like planet?

We focus here on whether the system would be stable and how the exo-Earth's eccentricity would be changed.

Unstable systems (planets ejecting or colliding): not habitable. Easy enough, except the question of whether an arbitrary 3-planet system is stable is, um, HARD. In this case, I used a bunch of different predictive techniques that have been developed by other scientists.

The question of whether an Earth-like planet is habitable and a given semi-major axis and eccentricity is likewise HARD. I (intentionally) use a very simple model here based on existing work in the field. This framework is very adaptable with other habitability models!

Weekly #space / #astrodon news update!

○ JWST is all aligned!
○ OSIRIS-REx ➡️ OSIRIS-APEX
○ bye bye SOFIA 😿
○ Rocket Lab caught (and dropped) Electron
○ pulsar caught hiding in plain sight
○ Black Hole Week...apropos, Event Horizon Telescope announcement next week!!

https://youtu.be/pThCr0IfJuU

@dgoldsmith Okay that makes me feel better. May just plan to do that at least for now!

I have not been able to bring myself to quit the bird app, and it feels like cheating to just post everything here and there, so I'm at a bit of a loss how to proceed here. In any case, I finally finished my summary video of the recent 2023-2032 Planetary Science & Astrobiology Decadal Survey! There's a lot to get into, so take a look! https://youtu.be/XxKQBbR6LrQ

@VistoTutti It needs to be finalized and submitted on Wednesday so not quiiite, but mostly! I don't even have to pull an all nighter!

Apparently I am only motivated by stress and panic, because I procrastinated my thesis corrections until I realized in a cold sweat last night that they're due in less than a week. Spent all day on it and now I'm on track to finish (I hope!).

@trinsec Thanks! I'm glad the auto-generated captions are decent. I'd love to have better quality captions but right now I don't have the bandwidth for it--it's on my list though!

@grb090423 Not at all! And thanks! I definitely am still learning the ropes, I feel like I've missed a dozen notifications already.

@bouncinglime @_astronoMay Absolutely! Welcome!

@_astronoMay Exoplanets are superior, it is known