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Reposted by Shashank Dholakia

Benjamin Pope @benjaminpope.bsky.social · 1d

In a companion paper, PhD student @maxecharles.bsky.social applies this to reconstructing complex images, not just fields of dots. We apply a regularised maximum likelihood method to restore clean, diffraction limited imaging by fitting directly to pixel level data.

Image reconstruction with the JWST Interferometer

Flying on board the James Webb Space Telescope (JWST) above Earth's turbulent atmosphere, the Aperture Masking Interferometer (AMI) on the NIRISS instrument is the highest-resolution infrared interfer...

arxiv.org

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Reposted by Shashank Dholakia

Benjamin Pope @benjaminpope.bsky.social · 1d

In the first paper Louis Desdoigts (ex PhD in my group, now Leiden postdoc) learns a model for the entire AMI system's optical physics together with a neural network 'effective detector model' the sensor, which suffers from a serious 'brighter-fatter effect' that blurs images at the pixel level.

AMIGO: a Data-Driven Calibration of the JWST Interferometer

The James Webb Space Telescope (JWST) hosts a non-redundant Aperture Masking Interferometer (AMI) in its Near Infrared Imager and Slitless Spectrograph (NIRISS) instrument, providing the only dedicate...

arxiv.org

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Reposted by Shashank Dholakia

Benjamin Pope @benjaminpope.bsky.social · 1d

Thrilled to have two years' of work out, in a pair of papers led by @gradientrider.bsky.social and @maxecharles.bsky.social.

We've built a data-driven calibration of the James Webb Interferometer to near its fundamental limits for high-res imaging - explainer at @aunz.theconversation.com!

How we sharpened the James Webb telescope’s vision from a million kilometres away

The only Australian hardware on board the legendary telescope is starting to fulfil its duties.

theconversation.com

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Reposted by Shashank Dholakia

George Monbiot @georgemonbiot.bsky.social · 7d

ME/CFS is a devastating condition that has long been denied, dismissed, psychologised and underdiagnosed. Research is at last starting to catch up with it, with glimmers of hope for those who have been left untreated for so long.
There's a huge BUT coming ...🧵
www.theguardian.com/society/2025...

Scientists develop first ‘accurate blood test’ to detect chronic fatigue syndrome

Research could offer hope for ME patients – but some experts urge caution and say more studies needed

www.theguardian.com

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Reposted by Shashank Dholakia

Sabina Sagynbayeva @sabinastro.bsky.social · 12d

Okay people, welcome my new paper into the world!!! With Isabel Colman and @farrwill.bsky.social

arxiv.org/abs/2510.02255

Rotation Periods for Stars in Open Cluster NGC 6819 From Kepler IRIS Light Curves

We present an updated catalog of stellar rotation periods for the 2.5 Gyr open cluster NGC 6819 using the Kepler IRIS light curves from superstamp data. Our analysis uses Gaussian Process modeling to ...

arxiv.org

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Shashank Dholakia @astroshashank.bsky.social · 8d

Yeah, it was labor intensive for sure. 15 mins for each video plus >100gb, but I'm a grad student so I've got time 😆

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Shashank Dholakia @astroshashank.bsky.social · 8d

It's all hand-tracked! I aligned the long axis of the camera in the direction of the drift and would recenter it every few seconds.

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Shashank Dholakia @astroshashank.bsky.social · 9d

And as a bonus, here's a false-color composite of the same. Blue is mapped to all of visible, green is infrared beyond 850nm, and red is the methane band at 889nm.

🔭 #astrophotography #saturn

An azure planet on a stark black background with neon orange-pink rings seen nearly edge-on.

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Shashank Dholakia @astroshashank.bsky.social · 9d

Been imaging Saturn while its rings are nearly edge-on and tried some infrared filters. At this 889nm methane band, Saturn strongly absorbs light, whereas its rings scatter equally across wavelengths.

Also a good visual demo of how astronomers measure exoplanet atmospheres!

🔭🧪 #astrophotography

Three images of Saturn from top to bottom: First, a standard RGB color image showing the rings nearly edge-on at about a 30 degree angle. Middle, a black and white image similar to above, but a little sharper taken with a filter that allows only wavelengths longer than 850nm. Lastly, at bottom, the rings seen as starkly white and the planet dark. This is a very narrow wavelength range of about 20nm centered on 889nm where methane absorbs light, making Saturn itself appear dark and the rings bright.

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Reposted by Shashank Dholakia

Kevin J. CREATURE @kevinjkircher.com · 10d

Sometimes I think about how from 1935-1975ish, Bell Labs produced an insane amount of revolutionary science and technology, including 11 Nobel Prizes, the transistor, UNIX, C, the laser, the solar cell, information theory, etc. The secret? Provide scientists with ample, steady, no-strings funding.

sites.stat.columbia.edu

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Reposted by Shashank Dholakia

Kevin J. CREATURE @kevinjkircher.com · 10d

Research also shows that spreading smaller amounts of funding out over more researchers generally delivers better scientific outcomes per dollar spent than focusing bigger grants on fewer researchers.

journals.plos.org/plosone/arti...

Big Science vs. Little Science: How Scientific Impact Scales with Funding

Agencies that fund scientific research must choose: is it more effective to give large grants to a few elite researchers, or small grants to many researchers? Large grants would be more effective only...

journals.plos.org

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Reposted by Shashank Dholakia

Mychal Threets @mychal3ts.bsky.social · 13d

There have been two hosts in the history of Reading Rainbow. The Legend of Literacy, LeVar Burton! And... me, Mychal Threets, a librarian 🥹🤯

I am a reader, a librarian because LeVar Burton and Reading Rainbow made us believe and see we belong in books, we belong everywhere ✨

youtu.be/e7es7qdWVnU

Smiling Mychal with hands raised wears an outer space shirt in a library. It is a still from an episode of Reading Rainbow.

LeVar Burton smiles with hands behind his head as he lies down on a colorful pile of books. ENEMY PIE book rests on his chest.

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Reposted by Shashank Dholakia

Abode Press @abodepress.bsky.social · 13d

Happy Pub Day to Earth and Earth-like Planets by Devaki D. Devi 🥳

Earth and Earth-like Planets is officially out for publication! 🧡 All pre-orders will be shipped as soon as possible.📦 If you haven't ordered your copy yet, you can purchase one here: www.abodepress.com/product-page...

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Shashank Dholakia @astroshashank.bsky.social · 13d

FFTs are pretty hard to beat in speed but restricting to the surface of a sphere and the analytic solution certainly helps! The goal is to do HMC on the surface map coefficients

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Shashank Dholakia @astroshashank.bsky.social · 13d

I believe @astromonnier.bsky.social has work on interferometrically detecting hot Jupiters from closure phases, maybe he'd have more to add about this

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Shashank Dholakia @astroshashank.bsky.social · 13d

🫩

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Shashank Dholakia @astroshashank.bsky.social · 13d

Need to take into account a few things like rotational and tidal deformation and stellar companions to do this well, but it's absolutely in the works!

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Reposted by Shashank Dholakia

Benjamin Pope @benjaminpope.bsky.social · 14d

This work owes a lot to ideas of and conversations with Rodrigo Luger, Keaton Burns, Geoff Vasil, and Ben Roberts, and it's been a really fun project with Shashank!

... and Shashank is on the postdoc market now, so if you're working on stars and planets, Jax, imaging science and applied maths...

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Shashank Dholakia @astroshashank.bsky.social · 13d

Thanks so much Will!!

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Shashank Dholakia @astroshashank.bsky.social · 13d

Thanks so much Brett!

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Shashank Dholakia @astroshashank.bsky.social · 13d

When you say you're going to work with spherical harmonics they make you sign an agreement to only use the plasma colormap

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Shashank Dholakia @astroshashank.bsky.social · 14d

Reposting for the #astro feed! 🔭

Shashank Dholakia @astroshashank.bsky.social · 14d

New paper by me and @benjaminpope.bsky.social! How well can we map a star using optical interferometry?

This is just a submitted preprint at the moment--comments and questions welcome! (1/N)

arxiv.org/abs/2509.25433

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Shashank Dholakia @astroshashank.bsky.social · 14d

However, we find that future, more densely spaced air Cherenkov arrays such as CTA might well be able to map stellar surfaces, especially for hot, blue chemically peculiar stars!

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Shashank Dholakia @astroshashank.bsky.social · 14d

Even with simultaneous photometry and regularizing assumptions, we can't map stars with current intensity interferometers. But bc intensity interferometers operate like radio interferometers and don't involve physically combining the light, it's possible to build them more densely (14/N)

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Shashank Dholakia @astroshashank.bsky.social · 14d

Lastly, we repeated this experiment for a technique called intensity interferometry, which has recently seen a revival from air Cherenkov telescopes, which during moonlit nights can be repurposed as interferometers. Pictured here is the VERITAS Array (13/N)

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