David Trevascus
@dtcupcakes.bsky.social
Astrophysics PhD student at MPIA Heidelberg 🇩🇪
Studying the formation of planets via direct imaging 🪐
he/they 🏳️🌈
Studying the formation of planets via direct imaging 🪐
he/they 🏳️🌈
A big thanks to Iain Hammond, who provided us with his new astrometry for PDS 70 d! You can find his paper about new detections of the planet candidate here: arxiv.org/abs/2504.11127
Keplerian motion of a compact source orbiting the inner disk of PDS 70: A third protoplanet in a resonance with b and c?
The disk around PDS 70 hosts two directly imaged protoplanets in a gap. Previous VLT/SPHERE and recent James Webb Space Telescope/NIRCam observations have hinted at the presence of a third compact sou...
arxiv.org
April 17, 2025 at 3:41 PM
A big thanks to Iain Hammond, who provided us with his new astrometry for PDS 70 d! You can find his paper about new detections of the planet candidate here: arxiv.org/abs/2504.11127
By comparing our new mass constraints to luminosity evolution models from Spiegel & Burrows (2012) we determined that PDS 70 b and c are both hot/warm-start planets!
April 17, 2025 at 3:41 PM
By comparing our new mass constraints to luminosity evolution models from Spiegel & Burrows (2012) we determined that PDS 70 b and c are both hot/warm-start planets!
In order to tell hot/cold-start you need planet masses, and a good way to get those is through orbit fitting. We do a lot of different orbit fits, some of which include the new planet candidate PDS 70 d!
April 17, 2025 at 3:41 PM
In order to tell hot/cold-start you need planet masses, and a good way to get those is through orbit fitting. We do a lot of different orbit fits, some of which include the new planet candidate PDS 70 d!
The differences between cold/hot-start planet formation are really important when we're searching for planets via direct imaging. Beta Pic b & c are hot-start, and so are the HR 8799 planets, but what about PDS 70 b & c?
April 17, 2025 at 3:41 PM
The differences between cold/hot-start planet formation are really important when we're searching for planets via direct imaging. Beta Pic b & c are hot-start, and so are the HR 8799 planets, but what about PDS 70 b & c?
I feel like people are overlooking the results of this paper which also came out today: arxiv.org/abs/2504.12030
tl;dr the amount of starlight being reflected into space by this planet is way too low to prevent a runaway greenhouse effect, which would not allow the existence of a liquid water ocean
tl;dr the amount of starlight being reflected into space by this planet is way too low to prevent a runaway greenhouse effect, which would not allow the existence of a liquid water ocean
Planetary albedo is limited by the above-cloud atmosphere: Implications for sub-Neptune climate
Energy limits that delineate the `habitable zone' for exoplanets depend on a given exoplanet's net planetary albedo (or `Bond albedo'). We here demonstrate that the planetary albedo of an observed exo...
arxiv.org
April 17, 2025 at 2:42 PM
I feel like people are overlooking the results of this paper which also came out today: arxiv.org/abs/2504.12030
tl;dr the amount of starlight being reflected into space by this planet is way too low to prevent a runaway greenhouse effect, which would not allow the existence of a liquid water ocean
tl;dr the amount of starlight being reflected into space by this planet is way too low to prevent a runaway greenhouse effect, which would not allow the existence of a liquid water ocean