Very sad news. Mike was also Treasurer for some of my time on Council and he did it superbly. He was also very friendly and I had many enjoyable conversations with him over the years.

Me, on astronomy funding crisis, on the @ox.ac.uk website: www.ox.ac.uk/news/2026-02... 🔭🧪

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 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?...

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 👀

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

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

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

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

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

Now we have Martin Barstow, taking the opportunity to embarrass me slightly (parental prerogative I suppose?) before going on to talk about white dwarfs as probes of exoplanet compositions. White dwarfs eat exoplanets for breakfast - they are good probes of rocky exoplanet composition. #HWO25

Thanks Laura for posting about my presentation!

We are back for the last session of #HWO25 with Michiel Min, describing the science case for observing cold gas giants via coronagraphy with HWO. The gas giants of our solar system have varied atmospheirc properties, clouds and chemistry. We need more targets to understand processes at work.

Next it's me! I'll be talking about observing transiting exoplanet phase curves with HWO 🙌 #HWO25

Now we have Kaz Gary, on masses of directly-imaged planets via ultra-high precision astrometry with HWO. Mass determination is important to correctly interpret spectra of potential biosignature host planets. Mass affects atmospheric structure, lack of knowledge hampers retrieval accuracy #HWO25

Next we have Marco Landoni, speaking about AI-assisted observation strategies for HWO. One of the things can that profitably be automated is scheduling, which can optimize the use of time. Bayesian inference and machine learning methods can both be used for this. #HWO25

Next we have Taro Matsuo speaking about the green sea hypothesis - the coevolution of Earth and life. The colour of the Earth is driven by the atmosphere but also the ocean. Cyanobacteria, the first organisms to use oxygen photosynthesis, used a range of pigments rather than chlorophyll. Why? #HWO25

Next is Anna Grace Ulses, talking about characterizing terrestrial exoplanet surfaces with reflected light spectroscopy. Oceans (habitability indicator), continents (oxygen false positive discriminator), vegetation and microbial mats are all important. #HWO25

Vanderburg: HWO will enable measurement of many many more contaminated white dwarf spectra and neural networks can be a big part of this. #HWO25

In the exoplanets/astrobiology parallel session this afternoon we start with Andrew Vanderburg, speaking about determining composition of rocky planets using AI. It's important to understand the range of rocky planet compositions in the solar neighbourhood to contextualise biosignatures #HWO25

Now we have the synthesis and vision discussion, led by Evgenya Shkolnik and John O'Meara. Shkolnik: HWO feels like a community-driven flagship mission. Aim is to keep that level of engagement throughout. Everyone here has been very excited, and despite challenging times the mood is hopeful. #HWO25

And, on that topic.... the next panel is on international partnerships. Panelists: Shawn-Domagal Goldman, Caroline Harper, Keigo Enya, Paul McNamara, Jean Dupuis; moderator Megan Ansdell. Representation from NASA, UKSA, JAXA, ESA and CSA. Long history of collaboration between all these. #HWO25

We now have an industry partnerships panel, panelists Jon Arenberg, Jeanette Domber, Matthew East and Alison Nordt; moderator Jim Oschman. Training the next generation of engineers and scientists is key because this is a long-duration mission. Advocacy for science (in general) also needed #HWO25

Now we have J. Scott Smith, discussing the road to mission concept review. We will be drawing on expertise and lessons learned from Hubble, JWST and Roman. MCR takes place prior to mission phase A. Traditionally, tech development happens in phase A, we are doing it early to mitigate risk #HWO25

We now have a second panel on emerging technologies, panelists Andrew Vanderburg, Tania Bedrax-Weiss, Dan Sirbu, Bernard Rauscher, Susan Redmond, John MacKenty; moderator Ruslan Belikov. AI technology is something that is emerging, could be used to speed up e.g. predictions/simulations. #HWO25

We now have a panel on astrophysics beyond 100 parsecs. Panelists: Sarah Tuttle, Eric Burns, Adam Smercina, Thaisa Storchi Bergmann, Allison Strom; moderator Janice Lee. First question is on the ideal lowest wavelength cutoff. 100 nm seems to be the consensus. #HWO25

Next we have Xinfeng Xu, talking about spatially resolving the fundamental elements of reionization in galaxies. Young, massive star clusters are fundamental to ionization. These have been observed in lensed galaxies at high redshift - strong lensing enables resolution of distant clusters. #HWO25

Good morning from the last day of #HWO25 - kicking off with Adam Smercina, talking about resolved stellar populations in nearby galaxies with HWO. Stars encode the evolutionary histories of galaxies. Measuring colour and brightness gives us their temperature and luminosity -> age and composition

Now we have Lynnae Quick who will be talking about cold ocean planets - exoplanet analogs of our solar system’s icy moons. Around 1/4 of terrestrial exoplanets are like to be geologically active ocean worlds, with about 2/3 of these likely to be cryovolcanic. HWO could detect such activity. #HWO25

Now we have Richard Cartwright talking about assessing ocean world habitability (eg Enceladus) with HWO. These are subsurface ocean worlds - global saline oceans at depth are sustained by tidal heating or radiogenic heat. #HWO25

Now we have Bryan Holler on characterizing physical properties and binarity of trans-Neptunian objects with HWO. These small bodies orbit beyond Neptune, currently over 5000 known. They are made of rock and ice. #HWO25

Now we have John Noonan talking about small body science with HWO. In the solar system we hypothesise that Jupiter’s formation divided the inner and outer solar system asteroid populations, but some observations seem to contradict this. Can HWO test hypotheses? #HWO25

Now we have Piero D’Incecco talking about using Venus and Earth as analogs for terrestrial exoplanets via the AVENGERS initiative (Analogs for VENus GEologically Recent Surfaces). Several field sites for this exist, one is Mount Etna in Sicily (compared with Idunn Mons on Venus.) #HWO25

Now we have Noam Izenberg, talking about whether we could observe Venus with HWO (yep, not exo-Venuses…. *actual* Venus). It would be very hard but we should totally do it! 👀 #HWO25

Now we're hearing from Fabien Malbet on very high precision astrometry for exoplanets and dark matter with HWO. As well as measuring astrometric variation of exoplanets, HWO can also measure extremely small proper motions of more distant objects to test dark matter models. #HWO25

Next is Eduardo Bendek talking about high-precision astrometry for direct imaging targets. Astrometry and radial velocity are complementary techniques, access different regions of parameter space. Astrometry and direct imaging together allow solving for semimajor axis and mass. #HWO25

Next up we have Rachel Fernandes on challenges in quantifying the frequency of Earth analogs in the habitable zone. eta Earth: frequency of Earth analogs (in mass/density) in the habitable zones (could have liquid water) of sun-like stars (same age, temperature, mass as the sun). #HWO25

Next we have Caleb Harada, on radial velocity masses of potential HWO targets. These measurements are also important to assess dynamical stability of systems (as other planets in the system may be identified). Giant planets in the habitable zone are bad news for potentially habitable worlds! #HWO25

Next is Renyu Hu, on distinguishing rocky planets, water worlds and gas dwarfs with HWO. Small exoplanets have diverse compositions. How can we tell them apart with HWO (bearing in mind: radius of non-transiting planets is unknown; mass may be unknown/lower limit). #HWO25

I should have said - we are now in parallel sessions for this afternoon so I am afraid I'm providing only the 1/3 of the content dedicated to exoplanets and solar systems. #HWO25

Now we have Courtney Dressing introducing the scientific discovery space for HWO. There is a paper summarizing the science case development documents, as an easy go-to for the range of community science interests. Over 65 science cases, many proposed observations can answer multiple questions #HWO25

Now we have Steven Finkelstein, talking about constraining galaxy evolution and reionization. We want to learn when the lights turned on in the universe - to do this, we need to observe galaxies at progressively earlier times/higher redshifts. #HWO25

Now we have the microphysics of dark matter with HWO from Bryce Wedig. What happens to dark matter at sub-galactic scales in sub-halos? Cold/warm/self-interacting dark matter models produce different small-scale structure. Frequency of different halo masses is diagnostic of different models #HWO25

Next is Jess Doppel discussing probing dark matter via ultra-faint satellite galaxies. In the current model, cold dark matter collapses to form halos, which merge to form larger halos. Galaxies tend to reside within these. Small scale model differences affect number of ultra-faint satellites. #HWO25

We're moving on to black holes now with Vivian U talking about unveilig intermediate mass black holes through reverberation mapping. Why do we care about black holes? They are important to galaxy evolution. Intermediate mass BHs are particularly interesting, but hard to observe. #HWO25

Next we have the biosignatures panel discussion. Panelists: Eddie Schwieterman, Tyler Robinson, Nick Wogan, Kevin Fogarty and Amber Young. Moderator Vikki Meadows. Reinforcing the importance of environmental context and confirmatory/negatory molecules for interpreting biosignatures. #HWO25

Next is Bethan James talking about galactic chemical evolution and the origins of life. Ultraviolet observations are key to tracing evolution of elements that make up biosignatures. Tracking chemical evolution within galaxies helps us understand how element distribution changed over time. #HWO25

Now we have Mary Anne Limbach on challenges and opportunities for detecting moons and exorings with HWO. If we had a super-HWO that could image all the planets in our solar system, in some cases rings/moons dominate the reflected light signal (Saturn's rings in particular, in the near-IR). #HWO25

Next we have Ligia Fonseca Coelho, speaking about surface biosignatures of cold, hot and dry exoplanets. Many factors influence the surface of a planet - geophysical considerations, impacts, atmospheric composition, the influence of the star - and also life. #HWO25