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Juliette Becker @jcbecker.bsky.social · 4d

I also wrote a blog post with a level of detail in between this post and the paper itself: becker.astro.wisc.edu/2025/10/09/n...

New paper: How Einstein’s Theory Might Help Planets Around White Dwarfs Stay Habitable

A new paper led by UW-Madison undergraduate Eva Stafne and published in ApJ this week (arXiv preprint here) explores how general relativity (the same physics that explains Mercury’s orbit) could help ...

becker.astro.wisc.edu

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Juliette Becker @jcbecker.bsky.social · 4d

Published this week in ApJ by UW-Madison undergraduate Eva Stafne: General relativity might save life on planets orbiting white dwarfs. GR-driven orbital precession can suppress tidal heating that would otherwise trigger a runaway greenhouse. arxiv.org/abs/2509.26421 #exoplanets

General Relativity Can Prevent a Runaway Greenhouse on Potentially Habitable Planets Orbiting White Dwarfs

Planets orbiting in the habitable zones of white dwarfs have recently been proposed as promising targets for biosignature searches. However, since the white dwarf habitable zone resides at 0.01 - 0.1 ...

arxiv.org

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Juliette Becker @jcbecker.bsky.social · 11d

I am an assistant professor at UW-Madison in the Department of Astronomy, and would like to share new research results.

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Juliette Becker @jcbecker.bsky.social · 11d

yes

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Juliette Becker @jcbecker.bsky.social · 11d

@bot.astronomy.blue signup

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Juliette Becker @jcbecker.bsky.social · Sep 4

So if you want the water to survive, the planet has to migrate late enough that the white dwarf has cooled and is not so bright in the XUV.

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Juliette Becker @jcbecker.bsky.social · Sep 4

Losing mass loss via Jeans escape is actually not easy (thermolysis occurs at 2000 K or hotter, and bonded H20 is very heavy and hard to lose). Photoevaporation will make the water vapor escape very easily, and white dwarfs are luminous in the XUV when young...

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Juliette Becker @jcbecker.bsky.social · Sep 4

Great question - we actually wrote a paper addressing just this: ui.adsabs.harvard.edu/abs/2025ApJ.... You are 100% right that this process requires high ecc and will cause tidal heating. The main effect (on water) of the tidal heating is to evaporate liquid water into the atmosphere as water vapor.

ui.adsabs.harvard.edu

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Juliette Becker @jcbecker.bsky.social · Sep 1

When stars die, could life begin? White dwarfs could possibly host planets with oceans, making them worth considering in the search for life.

I wrote about the science (and surprises) of white dwarf planets at The Conversation. theconversation.com/earth-size-s...

Earth-size stars and alien oceans – an astronomer explains the case for life around white dwarfs

Could tiny stars a fraction the size of our solar system’s Sun have habitable planets orbiting them? A new study says it’s possible.

theconversation.com

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Juliette Becker @jcbecker.bsky.social · Aug 22

Two weeks until abstracts (and requests for travel support) are due for this fall's GLEAM! gleam.astro.wisc.edu/overview/ I hope to see you here!

Juliette Becker @jcbecker.bsky.social · Jul 24

We’re so happy to host GLEAM 2025 at UW–Madison this Fall, Nov 6–7! gleam.astro.wisc.edu Join us for two days of exoplanets & community with a view of the shores of Lake Mendota. No registration fee. Travel support available. Abstracts & Travel Support Requests due Sept 5th. #exoplanets

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Juliette Becker @jcbecker.bsky.social · Jul 6

Definition question: Everyone in the field seems to use P~10 days as the boundary between "Hot" and "Warm" Jupiters in the literature. Does anyone know where this boundary actually came from (did a single person come up with it, and if so who / what paper)?

Reposted by Juliette Becker

American Astronomical Society (AAS) @aas.org · Jun 18

#AAS246 Chambliss Student Award Winners

The AAS is pleased to announce the Chambliss Astronomy Achievement Student Award winners from the 246th AAS meeting in Anchorage, Alaska, in June 2025. Congratulations, all! aas.org/posts/news/2... 🔭

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Reposted by Juliette Becker

UW–Madison Dept. of Atmospheric & Oceanic Sciences @uwmad-aos.bsky.social · Jun 18

AOS Prof. Hannah Zanowski studies polar oceanography, and she's now bringing that expertise to WiCOR, where she focuses on planetary oceanography by modeling early Earth and exoplanet conditions to understand what ultimately makes a planet habitable after it forms.

ls.wisc.edu/news/from-ea...

From Earth to Exoplanets: Studying Oceans Across the Universe

ls.wisc.edu

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Juliette Becker @jcbecker.bsky.social · Jun 18

Good question!! And Svetoslav is right, previous work by Madhusudhan et al. (arxiv.org/abs/2108.10888) found that Hycean planets are actually likely habitable to much lager distances due to their large masses which lead to large pressure & subsurface ocean (even if the top layer is ice, like Europa)

Habitability and Biosignatures of Hycean Worlds

We investigate a new class of habitable planets composed of water-rich interiors with massive oceans underlying H2-rich atmospheres, referred to here as Hycean worlds. With densities between those of ...

arxiv.org

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Juliette Becker @jcbecker.bsky.social · Jun 18

Congratulations, Irene, on this excellent (and very complete) paper!!

Irene Vargas-Salazar, PhD @irinipocket.bsky.social · Jun 17

🚨 Paper day!!! 🚨
Excited to announce that this project I’ve been working on these last few years has been published!
Read more at : arxiv.org/abs/2506.13004
More info in the 🧵

New Field OB and OBe Binaries of the SMC Wing: Observational Properties and Population Modeling

We present a radial velocity (RV) survey of the field OB and OBe stars of the SMC Wing. We use multi-epoch observations of 55 targets obtained with the Magellan IMACS and M2FS multi-object spectrograp...

arxiv.org

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Reposted by Juliette Becker

UW–Madison Science @uwmadscience.bsky.social · Jun 17

'Baby' stars are typically surrounded by disks loaded with gas, but it isn't long before that mass starts to drift away. #UWMadison astronomers say that might mean gas giants like Jupiter need to form earlier than rocky planets like ours. news.wisc.edu/measuring-ga...

Measuring gases around young stars, astronomers unlock major clues to planet formation

UW–Madison astronomers and international collaborators have produced the most accurate measurement of the gases swirling around young stars and their changing mass over time. The discovery offers clue

news.wisc.edu

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Juliette Becker @jcbecker.bsky.social · Jun 17

What does that mean? If a Hycean planet has a giant outer companion, tidal forces can perturb it out of the habitable zone, even if the incident stellar flux looks fine. You can find the accepted paper here:

Tides Tighten the Hycean Habitable Zone

Hycean planets -- exoplanets with substantial water ice layers, deep surface oceans, and hydrogen-rich atmospheres -- are thought to be favorable environments for life. Due to a relative paucity of at...

arxiv.org

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Juliette Becker @jcbecker.bsky.social · Jun 17

Here is a plot from Joseph's paper showing the effect - the transparent region was the location of the known habitable zone, the opaque region is the updated limits including tidal heating. For low mass stars, tides can make a difference!

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Juliette Becker @jcbecker.bsky.social · Jun 17

In a new paper accepted to ApJ Letters and on arXiv now, UW-Madison graduate student Joseph Livesey (astro.wisc.edu/staff/livese...) shows that tidal heating from even modest orbital eccentricity can heat close-in planets around M-dwarfs, shrinking the habitable zone significantly.

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Juliette Becker @jcbecker.bsky.social · Jun 17

Hycean planets (ocean worlds with H-rich atmospheres) are thought to be promising spots for life, particularly around M-dwarfs, with the habitable zone being much wider than it is for terrestrial planets. But there's a twist...

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Juliette Becker @jcbecker.bsky.social · Jun 13

Check out this 12-paper series out today from the AGE-PRO collaboration. Congrats to everyone (including Coco Zhang from UW Madison) on the huge amount of work that went into this interesting result!! It might take me a while to read all 12 papers though! public.nrao.edu/news/alma-pl...

ALMA Reveals Lives of Planet-Forming Disks - National Radio Astronomy Observatory

An international team of astronomers has unveiled groundbreaking findings about the disks of gas and dust surrounding nearby young...

public.nrao.edu

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Reposted by Juliette Becker

Kate Grier @grieratron.bsky.social · Jun 9

Ready to roll at #AAS246! I’ll be giving a talk on Tuesday afternoon in the AGN session and two of my students will be presenting in other AGN sessions as well!

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Juliette Becker @jcbecker.bsky.social · May 27

(Also thanks to the Big Ten Academic Alliance for making Open Access page charges free in PASP for any Big Ten researcher)

Juliette Becker @jcbecker.bsky.social · May 27

Check out our new paper in PASP!

Publications of the Astronomical Society of the Pacific (PASP) @paspjournal.bsky.social · May 22

A recent open-access @paspjournal.bsky.social article assesses the impact of episodic FU Orionis outbursts on the evolution and migration of planetary systems, providing an avenue for the observed prevalence of low-mass, iron-rich ultra short-period planets. iopscience.iop.org/article/10.1....

The ratio of the final mass of a planet after one FU Ori outburst event to the initial planet mass as a function of the local disk temperature. From Becker & Batygin (2025).

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