Kelly Lepo

Life update: December 31 was my last day at the Space Telescope Science Institute. The NASA's Universe of Learning grant that paid a large fraction of my salary was not renewed due to NASA budget cuts, so my contract was not renewed.

Why build two identical 8.1m telescopes on different continents? To see the whole universe! With Gemini North in Hawaii and Gemini South in Chile, the Gemini Observatory can access the entire night sky without blind spots. [1/5] #Astronomy #GeminiObservatory

This is so cool! White dwarfs are so much more colorful than their name would suggest. Pink and green stars!

Have you looked at the night sky recently? It is ABSURD how many satellites there are, and it will get >1000× worse in our lifetimes. A few billionaires and state actors will ruin the night sky for the next few *centuries*. This ought to be a much, much bigger story than it is

🔭 Ice Fishing for Cosmic Neutrinos Credit: NSF, B. Gudbjartsson, IceCube Collaboration ap261011

Added this wonderful anecdone from physicist Joanne Hewett, who was a postdoc at UW-Madison when Halzen first got the idea for IceCube. (1/2)  "We went to lunch on a cold winter day at the student union, as usual, and sat next to the window looking out over frozen Lake Mendota," she recalled.

Woot woot! Yay IceCube! Yay Francis!

I attended a seminar by freshly minted Nobel Laureate Francis Halzen many years ago and something he said stuck with me, but it takes some explaining, so this will be a (short) thread. The talk was about neutrino telescopes, and he started by explaining how rarely neutrinos interact with anything.

Astronomers theorize that the black hole at the center of Centaurus A influences the region as it feeds and launches powerful outflows. Learn more about the impact of its central black hole with a printable poster of this observation from #NASAWebb: https://go.nasa.gov/4hwsDlf

A successful Earth flyby improves Juice’s course to Jupiter Earlier today, Juice flew just 8640 km above the Indian Ocean and snapped these images with its onboard monitoring cameras. 1️⃣Africa, by Juice monitoring camera 2️⃣Madagascar, by Juice NavCam 3️⃣Moon, by Juice NavCam 🔭 🧪 #planetsci

PRIMA has been selected as NASA's first Probe Explorer mission! www.nasa.gov/news-release...

Giant telescope project rejects La Palma as backup site | Science | AAAS 🔭🧪 @science.org www.science.org/content/arti...

New Roman Space Telescope designs from Cepheid Studios have recently launched! Pin (shown below), necklace, earrings, and cufflinks in three colors of shiny acrylic, laser-cut with solar (and goat) power in France! shop.startorialist.com/products/nan... Psst @nancyromansci.bsky.social 🤩

One of my physics professors needed a source of alpha particles. Rather than buying it through official channels, he just brought a bunch of smoke detectors on eBay for their americium. So, if you showed up to an interview at his lab with an ionizing smoke detector, it might be a plus.

This starry view of the nearby star-forming region IC 348 sits just 1,000 light-years away in the constellation Perseus. Cold clouds of molecular hydrogen gas collapse to form new stars, creating glowing, sculpted scenes like this one. (1/5) 🧵 🔭

#NASARoman activated the Wide Field Instrument—a 300-megapixel infrared camera that will allow it to explore wide swaths of the cosmos quickly. This test image captures the very first photons of starlight to reach the instrument—taken as an initial performance assessment: https://go.nasa.gov/4rg4qEc

“As a result of exquisite planning by our orbital dynamics team, brilliant execution by the operations team, and a precise launch from SpaceX, Roman has fuel for at least 22 years of potential science operations,” said Jamie Dunn, center director at NASA’s Goddard Space Flight Center. #NASARoman 🔭

This week’s image is of the comet C/2025 K1 ☄️! Gemini’s GMOS-N captured this image, where you can see the comet's main body right beside two fragments that broke off! Check out the 🧵 for another paper. #Astronomy 📸 in thread

Six Hawaiʻi Island students helped bring a new Gemini North image to life! They selected the interacting galaxies NGC 7253 and gave them this Hawaiian name: Nā ʻUhane Māhoe Huki Pū i ke Ola, “The Twin Spirits Pulling Together Creating Life” #astronomy 📷 Gemini Observatory/NOIRLab/NSF/AURA

A happy goodbye is still a goodbye 🥹 Mission accomplished, MTM! 🫡 Thank you for the ride! Thanks to its solar-powered electric thrusters, MTM carried ESA's Bepi and JAXA's Mio to Mercury on the power equivalent of 250 ants! 🐜🐜🐜 🔭 🧪 #planetsci 1/3

This is good news! BepiColombo is a cool mission to orbit Mercury and will be there in less than three months. It flew there as two connected spacecraft, and they just separated successfully! www.science.esa.int/bepicolombo

The Nancy Grace Roman Space Telescope team has successfully activated the mission’s Coronagraph Instrument, which will block starlight to view planets and dusty disks around nearby stars. #NASARoman 🔭

We need your eyes! 🖥️ Introducing Rubin: Blobs and Blurs, a new citizen science project using NSF–DOE Rubin Observatory data. 🔭🧪 We’re on the hunt for faint, blurry galaxies that are dominated by invisible dark matter & often hard for computers to identify. zooniverse.org/rubin

At 12:02 p.m. EDT, the Nancy Grace Roman Space Telescope began an approximately 3-minute mid-course correction burn to adjust its trajectory toward its final orbit. #NASARoman 🔭

in case you missed it: Roman spacecraft separation #Roman 🔭🧪

Impress your family with trivia about the Nancy Grace Roman Space Telescope while you wait to watch the launch on Sunday morning! #NASARoman 🔭

Mooon. #eclipse

Lots of things suck lately, but also there's a partial lunar eclipse tonight! Go look! Partial begins at 10:34 PM eastern time, when it'll look like the Moon has a little bite out of it. The peak is 12:13 AM; it's 96%, so it should look reddish! www.timeanddate.com/eclipse/luna...

Ontario Lacus is a hydrocarbon lake near the south pole of Saturn’s moon Titan. Measuring 235 kilometers long by 75 kilometers across, Ontario Lacus is slightly smaller than its terrestrial counterpart, Lake Ontario. Lakes on Titan are named after lakes on Earth that are roughly the same size.

From @anaviuppal.bsky.social: In 2019, CHIME detected a very unusual fast radio burst (FRB) signal that excited the astronomical community. However, it turns out that the signal wasn’t from an FRB after all… ⚛️ 🔭 ☄️ 🧪 astrobites.org/2026/08/21/chime-misclassification/

Over the past days, unusually severe weather has affected northern Chile, where our observatories are located. This brought snow to Paranal and to the ELT construction site. It left stunning images, while causing severe flooding and damage to several cities within the Antofagasta Region. 🔭 1/2

This is a pleasing factoid: the Nancy Grace Roman space telescope is the same size and weight as a T-Rex! Countdown: 15 days to launch! 🚀 AUG 30, 2026 11:26 UTC ℹ️: science.nasa.gov/mission/roma...

During the recent Total Solar Eclipse the South Korean Danuri spacecraft obtained a nice view of Earth from Lunar orbit with the Moons shadow just visible on Earth. Here is their image, with attribution added, my colorized version and the nearly simultaneous EPIC-DSCOVR image used for the color.

How Two Medieval Scholars Used an Eclipse to Measure Longitude www.medievalists.net/2026/08/how-...