Jarron Leisenring
LightNews LightNews
banner
jarron.bsky.social
Jarron Leisenring
@jarron.bsky.social
290 followers 190 following 260 posts
Astronomer at Steward Observatory and Director of the Imaging Technology Lab. Worked on JWST NIRCam, ground-based AO, IR instrumentation and detectors, high contrast imaging, exoplanet and disks. Statements and opinions are my own. he/him
Posts Replies Media Videos
jarron.bsky.social
I just installed @skywatch.bsky.social filter earlier this week, and am pleased to say they're doing this job well. Not the first time I've seen them in the wild, but definitely the most prominent example so far!
Screen shot of @roxanegay fiercely responding to an asshole troll that has been automatically blocked and labelled appropriately for me by @skywatch.
June 28, 2025 at 1:32 AM
jarron.bsky.social
Apologies to my followers. The dam broke...
February 4, 2025 at 4:51 AM
jarron.bsky.social
If you're interested in blocking the account, someone else I follow posted it.
Account claiming to show a picture of Andromeda Galaxy taken by the Hubble Space telescope with no attribution. Be sure to block and not follow allabtgalaxy.bsky.social
November 26, 2024 at 3:20 AM
jarron.bsky.social
From last night.
November 21, 2024 at 8:29 PM
jarron.bsky.social
Bluesky now has over 10 million users, and I was #58,166, part of the first 1% to join.
Image showing my join date on 5/3/2023 puts me at #58166 of 10M users; part of the first 1%.
September 18, 2024 at 1:42 PM
jarron.bsky.social
Nausicaä from Hayao Miyazaki's "Nausicaä: Valley of the Winds" about to stab someone.
May 31, 2024 at 5:35 PM
jarron.bsky.social
You mean like this?
May 31, 2024 at 5:10 PM
jarron.bsky.social
Even saw a slight uptick in humidity measurements here in Tucson. Not sure if that’s real or just an effect of the instrument.

We were at 75% eclipse.
Solar radiation chart showing drop during eclipse from about 600 W/m^2 to 150 then rise back to 800. Slight dip in temperature by a couple F during eclipse. Very minor but consistent rise in measured humidity from 21% to 23% during eclipse.
April 9, 2024 at 5:06 AM
jarron.bsky.social
🧪 This small section of the image is pretty cool looking. Nicknamed "Baby Cas A", it's evidently an intricate light echo of dust that got warmed up by the initial explosion. It's about 170 ly behind Cas A supernova remnant.
NIRCam captured a particularly intricate and large light echo, nicknamed Baby Cas A by researchers that resembles a piece of molten glass. It is located about 170 light-years behind the supernova remnant.
December 11, 2023 at 3:31 AM
jarron.bsky.social
Hello, Cas A.

www.nasa.gov/missions/web...
side-by-side comparison of supernova remnant Cassiopeia A (Cas A) as captured by JWST NIRCam and MIRI. The outskirts of Cas A’s main inner shell, which appeared as a deep orange and red in the MIRI image, look like smoke from a campfire in the NIRCam image. The dust in the circumstellar material being slammed into by the shockwave is too cool to be detected directly at near-infrared wavelengths, but lights up in the mid-infrared. Also not seen in the near-infrared view is the loop of green light in the central cavity of Cas A that glows in mid-infrared, nicknamed the Green Monster by the research team.
December 11, 2023 at 3:17 AM
jarron.bsky.social
Obligatory Three Panel Soul: www.threepanelsoul.com/comic/how-pe...
How people think their car alarm works. Two people coming to the defense of a random car whose alarm is going off asking “Whose car is this anyway?” Response: “Don’t know but I’ll defend it with my life.”
October 20, 2023 at 7:57 AM
jarron.bsky.social
Welp…
Notification informing me that Google and Apple are shutting down COVID exposure notifications feature amid rising COVID infections.
September 18, 2023 at 6:34 PM
jarron.bsky.social
I read the paper. Here you go: www.nature.com/articles/s41...

While it talks about a series of issues with mega-constellations, the one relevant to your point dealt with how de-orbiting the satellites could cause ozone depletion and affect how the upper atmosphere absorbs and reflects light.
Paragraph of text, paraphrasing: "A 5-year cycle would see on average almost 2 tonnes re-entering Earth’s atmosphere daily. The satellites are mostly aluminum. Each mega-constellation will produce fine particulates that could greatly exceed natural forms of high-altitude atmospheric aluminum deposition, particularly if the full numbers of envisaged satellites are launched. Anthropogenic deposition of aluminum in the atmosphere has long been proposed in the context of geoengineering as a way to alter Earth’s albedo. Mega-constellations will begin this process as an uncontrolled experiment."
August 26, 2023 at 10:25 PM
jarron.bsky.social
Looks like it’s already available on Mac through Steam??
August 19, 2023 at 4:05 PM
jarron.bsky.social
Love my weather station. Here’s what we got in Tucson. Temperature dropped 40F. This came with quarter sized hail covering the yard and telephone poles snapped in half.
Outdoor temperature during thunderstorm showing 40F drop from 110 to 70F.
July 29, 2023 at 7:06 AM
jarron.bsky.social
After a year of science operations, we have enabled a new capability with JWST NIRCam coronagraphic observations that allows simultaneous acquisition of data in both SW+LW channels using the same mask. 🔭

https://www.stsci.edu/contents/news/jwst/2023/new-nircam-capability-is-now-available
Image of the white dwarf companion, HD 114174 B, observed in both SW and LW channels.
July 10, 2023 at 7:33 PM
jarron.bsky.social
Not sure how this all works here, but here is a picture of the debris disk around our relatively close neighbor Fomalhaut as observed by JWST/MIRI, led by András Gáspár. Press release: https://webbtelescope.org/contents/news-releases/2023/news-2023-109
May 8, 2023 at 4:22 PM