Dr Joanna Barstow

Great corset. Having never worn one, closest I’ve come is my wedding dress which had a very structured bodice but was adjusted to fit me - is it not horribly uncomfortable?

I’m definitely with you there! Innovation requires brains that have learned to think creatively. If we outsource our thinking to computers what will that result in long term?

Absolutely. Writing good papers also requires creativity IMO. At the end of the day it’s all about storytelling.

That was my immediate reaction too Chris. Sure, it’s expected in hydrogen dominated atmospheres for certain temperatures (so seeing it in a brown dwarf is cool but far from shocking). It’s still very much not expected in a CO2 or N2 dominated atmosphere. Caution always good, but context important!

It turns out the mob sing: ‘We don’t like what we don’t understand - in fact it scares us .’ Followed shortly after by cries to bring guns/knives and kill the Beast.

I feel like these lyrics are pretty key to the current shitshow we live in. Also, Howard Ashman was a genius.

I’m in an amateur production of Beauty and the Beast and in rehearsals last week we got around to learning/setting the Mob Song (the one with repeated calls to ‘Kill the Beast!’) I confess I never paid much attention to the details of the lyrics in the film…

If you don't know what's going on with anti-trans stuff in the UK, read this.

If you're similarly disgusted with the way anti-trans people have gotten away with demonising and assaulting an innocent minority, send this to your friends, family and MP to demand change.

They won't stop with us.

I don’t think there is an official repository yet. It would be excellent if it was part of the NASA Exoplanet archive but I think that would require an awful lot of investment they probably can’t make at the moment.

a cartoon character is sitting in a chair and says `` we 've forgotten the crackers '' . Alt: GIF of Wallace in A Grand Day Out waving his hands in horror at the realisation: ‘We’ve forgotten the crackers!’

Interstellar cheese? I think we all know who we need to investigate this…

YouTube video by OpenLearn from The Open University OpenLearn Podcast #3: Looking for life on exoplanets with Dr Jo Barstow

I had lots of fun last week recording a podcast episode for our OpenLearn team, which meant i got to wave my hands around a lot whilst talking about everything exoplanets - and of course, Habitable Worlds Observatory got an honourable mention. youtu.be/KXbo6OAKfoI?...

It’s about the difficulties a younger sibling has with everything the family does being about his brother. It might not all be a comfortable watch. But it is very well done.

There was a TV drama a few years ago called Coming Down the Mountain that was very good. Not sure if it was ever a book.

That's a wrap folks, #HWO25 is done! In 20 years I'll be posting on whatever social media platform then exists about Earthlike planet detections and maybe even signs of life 👀

Gupta: warmer planet T-p profiles lie completely in the miscible region. As a planet cools, eventually it will intersect the critical curve, and condensate clouds will emerge. Later there is deep 'rainfall' inside the planet, leading to water deep in the interior. TOI-270d too hot for this! #HWO25

Gupta: these simulations can help determine the critical curve defining the regions of pressure-temperature space where water is miscible in all proportions, and regions where hydrogen and water are only partially miscible. Uranus and Neptune have T-p profiles strikingly close to this curve. #HWO25

Gupta: insights into atmosphere-interior interactions are critical for interpreting HWO data. Lab experiments at relevant conditions are very hard though! Quantum mechanical methods (ab initio molecular dynamics) can help us understand interactions between hydrogen and water. #HWO25

Now our final talk, by Akash Gupta on the story of hydrogen and water - new insights into the interaction of planet atmospheres and interiors. Planet formation entails interaction of hydrogen envelope with interior - are these important? Yes - likely impact structure and thermal evolution #HWO25

Gialluca: however, there are big errors on estimated crater size with impactor energy. We need to do much more impact testing to understand this better. We therefore don't want a ~25 planet sample, this might end up being reduced by 50%, so we need contingency/conservative sample sizes #HWO25

Gialluca: in general impactors only start affecting yield if the energy is greater than 0.2 J. For a ~26J impactor similar to the JWST C3 impactor, this could result in a ~30% reduction in yield. #HWO25

Having a telescope barrel reduces stray light in two ways, it minimises the risk of impacts and minimises incident stray light from background sources. For high energy impactors, the background source improvement isn't that great, but it does protect against impacts happening in the 1st place #HWO25

Gialluca: this work provides order of magnitude estimates of stray light from these rare, high energy impact events. Two models exist for predicting crater size for a given impact - give different answers, so we have an optimistic to pessimistic range of possible sizes. #HWO25

Now we have Megan Gialluca on assessing the impact of stray light due to micrometeoroid damage. Micrometeoroid damage is unavoidable for space missions. JWST has seen a rate of a couple per month, consistent with pre-launch expectations - excepting the high energy event on the C3 mirror #HWO25

Wolff: shorter correlated noise lengthscales produce the widest posteriors, and shortest lengthscales match the width of absorption lines. E.g. oxygen posteriors can be biased here. PSF chromaticity produces correlated noise at these length scales. This will be a limiting noise source for HWO #HWO25

Wolff: speckle noise can be modelled using Gaussian processes, simply specified by an amplitude and length scale. Failing to model correlated noise in retrievals biases and artificially narrows posteriors. Most retrieval studies for HWO trade space do not yet account for speckle noise. #HWO25

Now we have Nicole Wolff talking about impacts of correlated noise on retrievals of exo-Earth atmospheres. Direct images contain chromatic speckles that move radially outward with wavelength. They are a source of spectrally correlated noise coupling adjacent wavelength bins. #HWO25

Stuber: hot exozodi could reduce HWO's performance drastically, but we don't know much detail about it yet. So every estimate of yield is highly uncertain and subject to this! #HWO25

Next we have Thomas Stuber, talking about hot exozodiacal dust and its effect on HWO's performance. Debris disks are circumstellar discs, gas poor, optically thin, composed of dust fragments left over from planetesimal fragmentation. Hot dust resides within ~1 au of the star, seen in near-IR #HWO25

Brugman: if magma on an exoplanet can't erupt then plate tectonics are suppressed, there is no crust recycling or volatile release, bioessential element recycling is restricted - planet is less likely to be habitable. #HWO25

Brugman: experimental petrology involves making exoplanet magma in the lab! Tests include looking at hydrogen solubility in magma ocean and phosphorus solubility in lava. Considering geochemical habitability is also really important - are surface conditions right for hosting life? #HWO25

Now we have Kara Brugman talking about goechemical habitability. Volcanoes are a crust factory for planets and also a mechanism for transporting volatiles from the interior to the surface and therefore atmosphere. Geochemical context is therefore critical for interpreting biosignatures. #HWO25