This planet cannot have been where it is today, so it went on a journey after the death of its star: rapid spiralling inwards or a high-eccentricity migration. But we don’t know which one happened.

This is where #JWST comes in. But little me cannot share more 🚫🤫Stay tuned! #ExSSV

Next up, we’ve got Sydney Jenkins on thermal emission from a giant planet transiting a white dwarf.

This is basically a sibling program to the talk before but they don’t want me to share this either, so stay tuned ☺️🚫🤫

#ExSSV

The next talk is by Andrew Vanderburg on #MEOW: a survey targeting white dwarf systems to study the prognosis of the solar system.

Mars might survive, but be roasted. The smaller gravity after the red giant phase will push the orbits further out. See pictures for a graphics.

Combining data from TESS and JWST, they’ve found one close-in TESS planet around a WD, and even after searching 10000 more, they cannot find another one; so this is rare!

So maybe we need to look further out.

#ExSSV

With the MEOW survey, they target around 20-30 WDs to find candidates. And they found a lot already (so maybe just contamination).

So we need to check:

The shape will give it away. Planet are not extended (galaxies are), so they need to be point sources.

The colour should be very red due to the temperature.

They identify one close-by planet, not even resolved with MIRI but follow-up is needed #ExSSV

Next up, we’ve got Sihao Cheng on occurrence rates of giant planets around B stars.

It is difficult to discover planets around massive stars, so our knowledge of planets around them is very limited. A way to do is to study white dwarfs as dependents of these massive stars.

In some infrared bands, a planet around a white dwarf may actually be brighter than the white dwarf itself, which is excellent for direct imaging. Especially for young systems, this is the case. #ExSSV

While this was an idea already 15 years ago, instrumentation has advanced significantly. They checked plenty of systems and found one candidate with colour excess. This candidate will be observed with #JWST (hopefully) soon.

Ground-based spectra show that the host is a fast-rotating WD that used to be a massive star. Future observations will tell what we’re looking at! #ExSSV

For the last talk of today, we’ve got Tim Cunningham on accreted planetary material determined from #xray observations.

Tim starts with the #exoplanet #HR diagram and points out polluted white dwarfs. Roughly 25-50% of the WD we know show metal pollution. This is expected to be happening when the star dies and kills its planetary system + then accretes the planetary material.

The accretion rates depend on the atmospheric models of WDs. #ExSSV