Jason Eastman
Jason Eastman
@exofast.bsky.social
Follow me for updates to EXOFASTv2, an IDL code to fit exoplanet data.
http://arxiv.org/abs/1206.5798
http://arxiv.org/abs/1907.09480
Harvard just denied my summer student hire "due to current and potentially impending federal funding freezes."

She's an amazing scientist with a bright future that just got a little dimmer, and we're all worse for it.
May 20, 2025 at 4:19 PM
Long overdue, but I've deactivated my twitter account and will be posting exclusively here going forward. I exported my old tweets and may retweet my most useful (instructional) ones here in the coming weeks.
January 22, 2025 at 4:35 PM
This is huge! This should make GPs within EXOFASTv2 fairly easy to implement.
Hi folks, I’ve written an IDL wrapper for Celerite2. If you have any suggestions on how to make it easier to use or encounter any issues, feel free to let me know.
github.com/wangxianyu7/...
GitHub - wangxianyu7/celerite2IDL: Fast & scalable Gaussian Processes in one dimension
Fast & scalable Gaussian Processes in one dimension - wangxianyu7/celerite2IDL
github.com
November 16, 2024 at 1:42 AM
The linkpars branch is now merged to master. This is a major update 2 years in the making, allowing multiple stars, automatically deblending transits based on multi-star sed fits, and linking parameters together via the prior file.

Please email me with any bug reports!
June 21, 2024 at 5:05 PM
Yikes... at some point, google calculator switched from r_jupiter = 7.1492e7 m (the equatorial radius, defined as "the jupiter radius" by IAU resolution B3 in 2015 arxiv.org/abs/1510.07674) to using r_jupiter = 6.6911e7 meters (the mean volumetric radius).

That's a 2% error.
IAU 2015 Resolution B3 on Recommended Nominal Conversion Constants...
Astronomers commonly quote the properties of celestial objects in units of parameters for the Sun, Jupiter, or the Earth. The resolution presented here was proposed by the IAU Inter-Division...
arxiv.org
May 30, 2024 at 7:27 PM
Proud dad moment: when your 6 year old takes your conference swag and dresses up as an astronomer for career day.

Prouder dad moment: at the bus stop, when someone asks, "oooo are you an astrologer?" she replies, "no, an asTRONomer." 🔭
February 29, 2024 at 1:49 PM
@jwstfeed.bsky.social

Not to steal Taylor Swift's #SuperBowl thunder, but my student, Regeneron finalist, and future Harvard undergrad Alexandra Mahajan led an exciting paper describing how to use JWST. to measure radii and temps of M dwarfs to 1%!
arxiv.org/abs/2402.05991
🔭🪐
Using JWST transits and occultations to determine $\sim1\%$...
Using JWST observations of a primary transit and two secondary eclipses for GJ 1214b, we determine an eccentricity that is more precise than a decade of HARPS data, which enables us to measure the...
arxiv.org
February 12, 2024 at 1:53 AM
Reposted by Jason Eastman
I just set up an automated way to send out invite codes to astro folk who request them 😁 I think I can send out about 100/day. 🔭

Donate any codes you have here: forms.gle/R35p4MRSwpk2...

& please share this code request form with other astro folks: forms.gle/GggKAPv8Vcrv...
October 7, 2023 at 4:35 PM
I made this animation of WASP-76 to explain global modeling and MCMC. Please feel free to use it.

lweb.cfa.harvard.edu/~jeastman/WA...
September 28, 2023 at 6:16 PM
Paper describing exofast's transit only eccentricity parameterization out today: arxiv.org/abs/2309.14410
September 27, 2023 at 4:51 AM
I pushed an update to the linkpars branch Friday that introduces the Mann 2019 Mass Ks relation. This is likely to evolve, but if you're interested in trying it out or have thoughts about how it would be most useful (or how much you believe the stated errors), feel free to reach out.
September 3, 2023 at 5:05 PM
I pushed an update to the linkpars branch that fixes all known bugs. This will be merged into the master branch after more thorough testing, and represents a major update that allows modeling an arbitrary number of stars and linking parameters together. More detail when the master branch is updated.
August 23, 2023 at 4:31 PM