iiinova — where your digital self keeps evolving

William Thompson @wrtastro.bsky.social · 09/12/2025

BTW the ride over WAS bumpy as indicated by the shock loggers… good thing everything survived in one piece thanks to the coil dampers in the crate

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William Thompson @wrtastro.bsky.social · 09/12/2025

SPIDERS is installed on the Subaru Naysmith platform and we got first fringes on from the upstream AO system. Next step, a real star! Huge thanks to Subaru, NAOJ, and the SCExAO teams for accommodating us. #exoplanets #instrumentation

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William Thompson @wrtastro.bsky.social · 23/10/2025

(most of) The local team together to see SPIDERS off! Fingers crossed the ride over wont be too bumpy 🫨

group photo around an astronomical instrument, inside a lab with a green wall in the background.

angle view of an astronomical instrument on a pallet

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William Thompson @wrtastro.bsky.social · 18/10/2025

SPIDERS is out of the clean room and almost ready to ship — it’s really happening! #instrumentation #exoplanets

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William Thompson @wrtastro.bsky.social · 29/09/2025

Paper accepted to AJ! 🥳 Updated preprint coming to an arxiv server near you.

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William Thompson @wrtastro.bsky.social · 02/09/2025

First day as a Plaskett Fellow 😎

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William Thompson @wrtastro.bsky.social · 29/08/2025

Last day as a Herzberg fellow 🥲

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William Thompson @wrtastro.bsky.social · 16/08/2025

To make it work, I had to pass “--overcommit” Story of my life…

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William Thompson @wrtastro.bsky.social · 16/08/2025

Probably nothing compared to TESS and Kepler though!

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William Thompson @wrtastro.bsky.social · 15/08/2025

#exoplanets As we speak, Octofitter is running on nearly 20,000 cores 😅 maybe a record for most exoplanet orbit fits run in parallel?

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William Thompson @wrtastro.bsky.social · 15/07/2025

These changes are breaking---See sefffal.github.io/Octofitter.j... for details. Thanks! [4/4]

sefffal.github.io

Migration Guide · Octofitter.jl

Documentation for Octofitter.jl.

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William Thompson @wrtastro.bsky.social · 15/07/2025

We have a new concept of “observation variables” that makes it easy to model out instrument systematics like RV offsets and northangle/platescale uncertainties. This plugs into our improved cross-validation capabilities to test how different subsets of data impact results. [3/4]

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William Thompson @wrtastro.bsky.social · 15/07/2025

We have a new API for constructing models and specifying priors, with much simpler syntax. It’s now really easy to e.g. add priors on mutual inclination between two bodies and other dynamical constraints. [2/4]

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William Thompson @wrtastro.bsky.social · 15/07/2025

Octofitter v7, now released! This release overhauls the modelling syntax and add some powerful new capabilities for advanced users. [1/4] (Octofitter is a package for Bayesian modelling of exoplanet orbits)

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Reposted by William Thompson

Brett Morris @brettmorr.is · 14/07/2025

The brightest star in Scorpius, Antares, is nearing the end of its 15 million year life. It's so large that the orbits of Mercury, Venus, Earth and Mars would be inside the star. 🔭🧪 Pilate et al. published brightness maps of the star, showing gigantic convective cells. arxiv.org/abs/2507.08614

Relative brightness maps of Antares over the course of a year, showing the changing brightness and shapes of convective cells in the stellar photosphere.

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William Thompson @wrtastro.bsky.social · 12/07/2025

Direct imagers, what is your expectation for how speckles behave at high spectral resolution? Do they vary smoothly with wavelength? We have an R11,000 cube at 10^-7 contrast to share soon, but I’m curious to hear people’s expectations first #instrumentation #exoplanets.

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William Thompson @wrtastro.bsky.social · 10/07/2025

Position of Epsilon Eridani b in-front/behind the star, and phase angle over time for those interested. Updated pre-print should be ready soon! 🔭 #exoplanets

a plot of a planet's position vs the star in 2D indicated as coloured lines. The line colour goes towards red or blue as the planet is in front of the star or behind. It is blue on the left, red on the right, and green, indicating 0, at the top and bottom. The separation is about 1000 milliarcseconds left or right increasing to about 1300 at top or bottom, creating an oval.

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William Thompson @wrtastro.bsky.social · 06/07/2025

There’s something very special about the gulf islands 🏝️

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Reposted by William Thompson

Jayke Samson Nguyen @jayke.io · 02/07/2025

Found some beautiful Neptune data digging through the Keck Observatory Archives! The pole isn't nearly as visible now as it was back in 2002.

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William Thompson @wrtastro.bsky.social · 03/06/2025

I was honoured today to give the Plaskett medal award talk to open this years Canadian Astronomical Society meeting in Halifax! Great to share our work on #exoplanets imaging and modelling 🔭

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Reposted by William Thompson

Heidi B. Hammel @hbhammel.bsky.social · 27/05/2025

Astonishing new videos of the Sun show coronal "rain" in (pink-tinted) hydrogen-alpha light. Obtained with advanced adaptive optics research supported by NSF, the National Solar Observatory, and New Jersey Institute of Technology. Details and more videos in the link in the first comment below.

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William Thompson @wrtastro.bsky.social · 22/05/2025

Link: sefffal.github.io/Octofitter.j... Change log: github.com/sefffal/Octo... Fig. credits: * arxiv.org/abs/2504.11127 * arxiv.org/abs/2502.05359 * arxiv.org/abs/2502.20561 Thanks to: * Dori Blakley * Eric Nielsen * William Roberson * Zach Langford * Eric Agol * Sarah Blunt * Clarissa R Do Ó

sefffal.github.io

Home · Octofitter.jl

Documentation for Octofitter.jl.

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William Thompson @wrtastro.bsky.social · 22/05/2025

Octofitter v6 just released! 🐙 * Overhauled Hipparcos / Gaia modelling * Multi-planet epicycle approximation * Include astrometric jitter, north angle, and plate-scale uncertainties * Dynamical priors (prevent crossing) * Celerite gaussian processes Much more! (fig. credit in reply) #exoplanets 🔭

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Aniket Sanghi @astroaniket.bsky.social · 17/05/2025

Check out our short update on JWST mid-infrared observations of the closest Sun-like star, Alpha Centauri A! iopscience.iop.org/article/10.3...

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Reposted by William Thompson

Paul Byrne @theplanetaryguy.com · 07/05/2025

Credit: Jason Wang/William Thompson/Christian Marois/Quinn Konopacky Access the video and related data here: jasonwang.space/orbits.html

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William Thompson @wrtastro.bsky.social · 29/04/2025

Unfortunately no, although we used to have a little LED to act as a planet 😅 Now we just inject fake planets with software when we need to.

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William Thompson @wrtastro.bsky.social · 29/04/2025

Here's a bonus video of SPIDERS maintaining a dark hole in real time, despite simulated turbulence!

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William Thompson @wrtastro.bsky.social · 29/04/2025

Amazingly, this bright interference pattern is super robust to vibrations, atmospheric turbulence, etc thanks to a common-path design. Any physical vibration affects both arms of the interferometer equally, requiring no active vibration compensation. SPIDERS ships this fall! [3/3]

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William Thompson @wrtastro.bsky.social · 29/04/2025

Starlight can interfere with itself, but not with light from planets and disks, so fringed = speckle, and unfringed = planet (if within ~0.5" of the star, where the reference beam is). This lets us measure and remove speckles using our deformable mirror without any probing. [2/3]

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William Thompson @wrtastro.bsky.social · 29/04/2025

Recent images from our SPIDERS pathfinder instrument demonstrating the self-coherent camera--next generation tech for direct imaging of exoplanets! We use a special coronagraph to interfere the starlight with itself, like a classic double slit experiment... [1/3] 🔭 #Instrumentation #exoplanets

fringed image of star behind coronagraph

unfringed image of star behind coronagraph

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Reposted by William Thompson

Physics & Astronomy at UVic @phys-astro-uvic.bsky.social · 26/03/2025

Congratulations to Dr. William Thompson '23, of ARC and NRC-Herzberg, who was named as the recipient of the 2025 CASCA Plaskett Medal and the NRC Herzberg Plaskett Fellowship for Most Outstanding Doctoral Thesis in Astronomy or Astrophysics 🎉 #UVic #UVicScience #CASCA #ARC #NRCHerzberg #Astronomy

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William Thompson @wrtastro.bsky.social · 25/03/2025

Thanks also to my external examiner Dr. Charles Beichman for his kind words: > it is the combination of innovative thinking, rigorous simulation and laboratory testbed results which make the work so impressive

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William Thompson @wrtastro.bsky.social · 25/03/2025

I learned today that am being awarded the J.S. Plaskett medal for most outstanding doctoral thesis in astronomy in Canada. Thank you @casca.ca.web.brid.gy, and my committee for the nomination! 🔭

CASCA is pleased to announce Dr. William Thompson as the 2025 recipient of the Plaskett Medal for the most outstanding doctoral thesis in astronomy or astrophysics.

Dr. Thompson’s thesis, defended at the University of Victoria in 2023 under the direction of Profs. Falk Herwig and Christian Marois, is entitled, “Lights in Motion: Observing Nearby Planets with Imaging, Wavefront Sensing, Orbital Detection, and Spectroscopy”. The title hints at the breadth of the research described within Dr. Thompson’s thesis work, including developing new computational methods to analyze angular differential imaging observations and employing these methods to discover a new candidate exoplanet around HR 8799; developing the first multi-technique exoplanet finding code that can incorporate radial velocity, astrometry and high-contrast imaging data; carrying out both simulation and laboratory tests of two new techniques for exoplanet imaging; and more. The thesis external examiner notes that, “it is the combination of innovative thinking, rigorous simulation and laboratory testbed results which make the work so impressive.” The software developed as part of Dr. Thompson’s thesis research is publicly available and is already being used by other exoplanet researchers, and his instrumentation development work provides first steps toward possible hardware contributions to the Habitable Worlds Observatory. CASCA is delighted to recognize Dr. Thompson for these outstanding contributions.

La CASCA a le plaisir d’annoncer que le M William Thompson, Ph. D., est le lauréat de la médaille J.S. Plaskett 2025 pour la thèse de doctorat la plus remarquable en astronomie ou en astrophysique.

La thèse du M Thompson, Ph. D., soutenue à l'Université de Victoria en 2023 sous la direction des Profs. Falk Herwig et Christian Marois, est intitulée « Lumières en mouvement : observation de planètes proches à l'aide de l'imagerie, de la détection de front d'onde, de la détection orbitale et de la spectroscopie ». Le titre fait allusion à l'ampleur de la recherche décrite dans la thèse. Les travaux de thèse du M Thompson, Ph. D., comprenaient le développement de nouvelles méthodes de calcul pour analyser les observations d'imagerie différentielle angulaire et l'utilisation de ces méthodes pour découvrir une nouvelle exoplanète candidate autour de HR 8799 ; le développement du premier code multitechnique de recherche d'exoplanètes capable d'intégrer la vitesse radiale, l'astrométrie et les données d'imagerie à contraste élevé ; la réalisation de simulations et de tests en laboratoire de deux nouvelles techniques d'imagerie d'exoplanètes, et plus encore. L'examinateur externe de la thèse note que « c'est la combinaison d'une pensée innovante, d'une simulation rigoureuse et de résultats de banc d'essai en laboratoire qui rend le travail si impressionnant ». Le logiciel mis au point dans le cadre de la thèse du M Thompson, PhD, est accessible à tous et est déjà utilisé par d'autres chercheurs sur les exoplanètes, et son travail de développement d'instrumentation constitue un premier pas vers d'éventuelles contributions matérielles à l'Observatoire des mondes habitables. La CASCA est ravie de souligner les réalisations de M Thompson, Ph. D., en lui décernant ce prix.

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Space Telescope Science Institute @stsci.edu · 17/03/2025

The James Webb Space Telescope imaged young, giant exoplanets and detected carbon dioxide! The findings suggest that the giant exoplanets in the HR 8799 system likely formed like Jupiter and Saturn. (1/5) 🔭 🧪 🧵

This image shows the planetary system HR 8799. The background is black. At the center there is a symbol representing a star labeled HR 8799. The star’s light is blocked. There are four exoplanets, which look like fuzzy dots, pictured surrounding the star. Furthest from the star is a fuzzy, faint blue dot, labeled b, at the 10 o’clock position. At the 1 o’clock position, second furthest from the star is a blueish-white fuzzy dot labeled c. Just below that is an orange dot labeled e. At the 4 o’clock position, still near the star, is another fuzzy white dot labeled d.

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William Thompson @wrtastro.bsky.social · 16/03/2025

This is fantastic news. Upping grad and postdoc awards (both stipend and amount), and finally allowing non-Canadian/PRs to apply.

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William Thompson @wrtastro.bsky.social · 04/03/2025

Here are some individual draws from the posterior. I think any individual row should work. The angular parameters are in units of radians, period in years, tp in MJD (ps: plain text copyable version in the alt-text). We'll post the full posteriors and reproducible scripts once accepted.

A plain text data table that reads:

M_pri b_e b_ω b_τ b_P b_i b_Ω b_a b_tp b_mass
Float64 Float64 Float64 Float64 Float64 Float64 Float64 Float64 Float64 Float64
──────────────────────────────────────────────────────────────────────────────────────────────────
0.831638 0.168298 3.89686 0.858561 7.21718 0.640533 3.29034 3.51345 59651.7 1.06503
0.795307 0.0308685 5.94108 0.169789 7.28537 0.874402 2.96544 3.48309 57840.3 0.879026
0.849784 0.133792 4.07826 0.885673 7.3039 0.7676 3.17299 3.56694 59751.3 0.962535
0.828249 0.0122253 2.14998 0.58055 7.33537 0.621978 3.60262 3.54694 58943.9 1.11392
0.830251 0.120784 5.83218 0.16658 7.32244 0.914066 3.4074 3.54528 57834.0 0.866626
0.843352 0.105946 4.02053 0.889047 7.3851 0.739503 3.33878 3.58424 59786.6 0.955619
0.843297 0.0298729 0.202907 0.251375 7.37376 0.68507 3.18727 3.58067 58065.5 1.08521
0.842145 0.0804329 5.19621 0.0807889 7.38184 0.878696 3.38147 3.58141 57606.3 0.903373
0.831515 0.0393159 5.18298 0.0626671 7.43359 0.73388 3.33258 3.5833 57558.6 1.16991
0.802696 0.0307339 0.643902 0.324703 7.22671 0.642977 3.42096 3.47524 58245.6 1.01233

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William Thompson @wrtastro.bsky.social · 04/03/2025

The stars photocentre is apparently moving by more than the radius of the star, and in sync with the RV. It’d be hard to explain that away with stellar activity IMO.

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William Thompson @wrtastro.bsky.social · 04/03/2025

Part of our work was independently confirming the orbital period using only absolutely astrometry for the first time— no RV. The periods line up perfectly. This planet is real or I’ll eat my hat!

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