Kelly Lepo
@kellylepo.bsky.social
Astronomer | Science communicator | Adult Lisa Simpson
Education and Outreach Scientist at the Space Telescope Science Institute (@stsci.edu) supporting JWST.
Personal account — Views are my own
Also on Mastodon: @KellyLepo@scicomm.xyz
Education and Outreach Scientist at the Space Telescope Science Institute (@stsci.edu) supporting JWST.
Personal account — Views are my own
Also on Mastodon: @KellyLepo@scicomm.xyz
Happy launch anniversary JWST!
The telescope launched on December 25, 2021 on an Ariane 5 rocket from the European Spaceport near Kourou, French Guiana.
Thanks to the hard work of the people at ESA, JWST had a fantastic start to its trip out to its parking spot 1.5 million km away at L2.
The telescope launched on December 25, 2021 on an Ariane 5 rocket from the European Spaceport near Kourou, French Guiana.
Thanks to the hard work of the people at ESA, JWST had a fantastic start to its trip out to its parking spot 1.5 million km away at L2.
James Webb Space Telescope Launch Highlights
YouTube video by Space Telescope Science Institute
www.youtube.com
December 25, 2025 at 10:59 PM
Happy launch anniversary JWST!
The telescope launched on December 25, 2021 on an Ariane 5 rocket from the European Spaceport near Kourou, French Guiana.
Thanks to the hard work of the people at ESA, JWST had a fantastic start to its trip out to its parking spot 1.5 million km away at L2.
The telescope launched on December 25, 2021 on an Ariane 5 rocket from the European Spaceport near Kourou, French Guiana.
Thanks to the hard work of the people at ESA, JWST had a fantastic start to its trip out to its parking spot 1.5 million km away at L2.
Reposted by Kelly Lepo
Hubble has imaged the largest planet-forming disk ever seen! At 400 billion miles wide, it is roughly 40 times the diameter of our solar system. The disk is unexpectedly chaotic and turbulent, offering new insights into how planetary systems form: https://bit.ly/477sQ9b 🔭 🧪
December 23, 2025 at 2:07 PM
Hubble has imaged the largest planet-forming disk ever seen! At 400 billion miles wide, it is roughly 40 times the diameter of our solar system. The disk is unexpectedly chaotic and turbulent, offering new insights into how planetary systems form: https://bit.ly/477sQ9b 🔭 🧪
Reposted by Kelly Lepo
Happy Winter Solstice!
Beer can, pinhole camera photos of the Summer to Winter Solstice (2024) and the Winter to Summer Solstice (2025).
You never know quite what you're going to get with these photos, set the beer can pointing towards the sun at hopefully the correct angle and wait 6 months!
Beer can, pinhole camera photos of the Summer to Winter Solstice (2024) and the Winter to Summer Solstice (2025).
You never know quite what you're going to get with these photos, set the beer can pointing towards the sun at hopefully the correct angle and wait 6 months!
December 21, 2025 at 3:26 PM
Happy Winter Solstice!
Beer can, pinhole camera photos of the Summer to Winter Solstice (2024) and the Winter to Summer Solstice (2025).
You never know quite what you're going to get with these photos, set the beer can pointing towards the sun at hopefully the correct angle and wait 6 months!
Beer can, pinhole camera photos of the Summer to Winter Solstice (2024) and the Winter to Summer Solstice (2025).
You never know quite what you're going to get with these photos, set the beer can pointing towards the sun at hopefully the correct angle and wait 6 months!
Happy Solstice everyone!
December 22, 2025 at 1:11 AM
Happy Solstice everyone!
Reposted by Kelly Lepo
Happy December Solstice! 🌞
It’s summer at NSF–DOE Rubin Observatory in Chile! Wildflowers? Blooming. Skies? Clear. Sun? Vibing. ☀️
Sending warm thoughts to the northern hemisphere! ❄️
It’s summer at NSF–DOE Rubin Observatory in Chile! Wildflowers? Blooming. Skies? Clear. Sun? Vibing. ☀️
Sending warm thoughts to the northern hemisphere! ❄️
December 21, 2025 at 4:10 PM
Happy December Solstice! 🌞
It’s summer at NSF–DOE Rubin Observatory in Chile! Wildflowers? Blooming. Skies? Clear. Sun? Vibing. ☀️
Sending warm thoughts to the northern hemisphere! ❄️
It’s summer at NSF–DOE Rubin Observatory in Chile! Wildflowers? Blooming. Skies? Clear. Sun? Vibing. ☀️
Sending warm thoughts to the northern hemisphere! ❄️
The first data from NASA's SPHEREx mission are out!
Check out this video, showing the entire sky in infrared light. The Milky Way runs as a band across the center. Each frame shows a different infrared wavelength, with light from stars, hot gas, and cosmic dust. 🔭🧪
www.jpl.nasa.gov/news/nasas-s...
Check out this video, showing the entire sky in infrared light. The Milky Way runs as a band across the center. Each frame shows a different infrared wavelength, with light from stars, hot gas, and cosmic dust. 🔭🧪
www.jpl.nasa.gov/news/nasas-s...
SPHEREx First All-Sky Map — Spectrum
YouTube video by JPLraw
youtu.be
December 19, 2025 at 7:11 PM
The first data from NASA's SPHEREx mission are out!
Check out this video, showing the entire sky in infrared light. The Milky Way runs as a band across the center. Each frame shows a different infrared wavelength, with light from stars, hot gas, and cosmic dust. 🔭🧪
www.jpl.nasa.gov/news/nasas-s...
Check out this video, showing the entire sky in infrared light. The Milky Way runs as a band across the center. Each frame shows a different infrared wavelength, with light from stars, hot gas, and cosmic dust. 🔭🧪
www.jpl.nasa.gov/news/nasas-s...
Reposted by Kelly Lepo
I mean, just check out this stunning new image from SPHEREx, the latest NASA space mission. It's mapping the full sky in 102 colors, and choosing the right combinations can reveal different information about the Universe. Here's our galaxy in infrared colors that pick out stars:
December 19, 2025 at 4:11 PM
I mean, just check out this stunning new image from SPHEREx, the latest NASA space mission. It's mapping the full sky in 102 colors, and choosing the right combinations can reveal different information about the Universe. Here's our galaxy in infrared colors that pick out stars:
Reposted by Kelly Lepo
I wanted to do a quick thread about this paper led by a great postdoc here at JPL, Flavio Petricca, which suggests that Titan may not have a global ocean after all. www.nasa.gov/solar-system...
NASA Study Suggests Saturn’s Moon Titan May Not Have Global Ocean - NASA
A key discovery from NASA’s Cassini mission in 2008 was that Saturn’s largest moon Titan may have a vast water ocean below its hydrocarbon-rich surface. But
www.nasa.gov
December 18, 2025 at 4:36 PM
I wanted to do a quick thread about this paper led by a great postdoc here at JPL, Flavio Petricca, which suggests that Titan may not have a global ocean after all. www.nasa.gov/solar-system...
I had a blast walking with the @stsci.edu float for the Mayor’s Christmas Parade in Baltimore on Sunday.
December 15, 2025 at 7:19 PM
I had a blast walking with the @stsci.edu float for the Mayor’s Christmas Parade in Baltimore on Sunday.
Reposted by Kelly Lepo
Vibert Douglas fought against gender discrimination in her field, earned an MBE for her war service, was a celebrated astrophysicist and one of the first individuals to receive the Order of Canada.
This is her remarkable story.
🧵 1/8
This is her remarkable story.
🧵 1/8
December 15, 2025 at 2:01 PM
Vibert Douglas fought against gender discrimination in her field, earned an MBE for her war service, was a celebrated astrophysicist and one of the first individuals to receive the Order of Canada.
This is her remarkable story.
🧵 1/8
This is her remarkable story.
🧵 1/8
One of my favorite recent JWST images, Pismis 24, is now available as a free downloadable poster. Perfect for printing and decorating your walls.
It includes the image on the front and a description in both English and Spanish on the back. 🔭🧪
science.nasa.gov/asset/webb/p...
It includes the image on the front and a description in both English and Spanish on the back. 🔭🧪
science.nasa.gov/asset/webb/p...
December 12, 2025 at 9:49 PM
One of my favorite recent JWST images, Pismis 24, is now available as a free downloadable poster. Perfect for printing and decorating your walls.
It includes the image on the front and a description in both English and Spanish on the back. 🔭🧪
science.nasa.gov/asset/webb/p...
It includes the image on the front and a description in both English and Spanish on the back. 🔭🧪
science.nasa.gov/asset/webb/p...
Reposted by Kelly Lepo
SAVE THE DATE: Dr. Stefanie Milam will discuss how #NASAWebb is revealing details across the Solar System that were not previously known—December 17 at 4 p.m. ET.
Planets, Asteroids, and Interstellar Interlopers, OH MY! Revealing the Solar System with JWST
YouTube video by Space Telescope Science Institute
www.youtube.com
December 12, 2025 at 7:48 PM
SAVE THE DATE: Dr. Stefanie Milam will discuss how #NASAWebb is revealing details across the Solar System that were not previously known—December 17 at 4 p.m. ET.
Reposted by Kelly Lepo
🔭 Now it's official, the nebula was never in Andromeda!
Our paper has been published and we show that the large 🧪 oxygen nebula is in the Milky Way.
This arc was discovered by amateurs photographing Andromeda with an [O III] filter, and now we have new things to say... ⚛️
Our paper has been published and we show that the large 🧪 oxygen nebula is in the Milky Way.
This arc was discovered by amateurs photographing Andromeda with an [O III] filter, and now we have new things to say... ⚛️
December 11, 2025 at 10:03 PM
🔭 Now it's official, the nebula was never in Andromeda!
Our paper has been published and we show that the large 🧪 oxygen nebula is in the Milky Way.
This arc was discovered by amateurs photographing Andromeda with an [O III] filter, and now we have new things to say... ⚛️
Our paper has been published and we show that the large 🧪 oxygen nebula is in the Milky Way.
This arc was discovered by amateurs photographing Andromeda with an [O III] filter, and now we have new things to say... ⚛️
Space telescopes are way more expensive than ground-based telescopes, for reasons including:
• Launch costs
• No atmosphere means more radiation and more expensive electronics
• Can't fix them if they break, so they need way more testing and better hardware
• Cooling in space is very hard, actually
• Launch costs
• No atmosphere means more radiation and more expensive electronics
• Can't fix them if they break, so they need way more testing and better hardware
• Cooling in space is very hard, actually
Just because it's being passed around a lot: NO, data centers in space do NOT benefit from space being cold. Space is cold in the formal sense we use to define temperature. But it is very bad at cooling. What would you rather have to cool hot metal: a lukewarm water tub or a giant cold atmosphere?
December 10, 2025 at 4:39 PM
Space telescopes are way more expensive than ground-based telescopes, for reasons including:
• Launch costs
• No atmosphere means more radiation and more expensive electronics
• Can't fix them if they break, so they need way more testing and better hardware
• Cooling in space is very hard, actually
• Launch costs
• No atmosphere means more radiation and more expensive electronics
• Can't fix them if they break, so they need way more testing and better hardware
• Cooling in space is very hard, actually
Reposted by Kelly Lepo
Hubble reobserved interstellar comet 3I/ATLAS on November 30. At the time, the comet was about 178 million miles (286 million kilometers) from Earth.
Hubble tracked the comet as it moved across the sky. As a result, background stars appear as streaks of light: https://go.nasa.gov/4iCU2lH 🔭 🧪
Hubble tracked the comet as it moved across the sky. As a result, background stars appear as streaks of light: https://go.nasa.gov/4iCU2lH 🔭 🧪
December 4, 2025 at 3:31 PM
Hubble reobserved interstellar comet 3I/ATLAS on November 30. At the time, the comet was about 178 million miles (286 million kilometers) from Earth.
Hubble tracked the comet as it moved across the sky. As a result, background stars appear as streaks of light: https://go.nasa.gov/4iCU2lH 🔭 🧪
Hubble tracked the comet as it moved across the sky. As a result, background stars appear as streaks of light: https://go.nasa.gov/4iCU2lH 🔭 🧪
Reposted by Kelly Lepo
I have eaten
the planets
that were in
the inner solar system
and which
you were probably
saving
for living on
Forgive me
they were delicious
so crunchy
and so warm
the planets
that were in
the inner solar system
and which
you were probably
saving
for living on
Forgive me
they were delicious
so crunchy
and so warm
Elderly stars just get hungry, and orbiting planets are *right there.* 🔭🧪
New research from Edward Bryant @uni-of-warwick.bsky.social and Vincent Van Eylen @University College London, input from Sabine Reffert @uniheidelberg.bsky.social, story by @bowlerhatscience.org. eos.org/articles/pla...
New research from Edward Bryant @uni-of-warwick.bsky.social and Vincent Van Eylen @University College London, input from Sabine Reffert @uniheidelberg.bsky.social, story by @bowlerhatscience.org. eos.org/articles/pla...
Planet-Eating Stars Hint at Earth’s Ultimate Fate - Eos
A sampling of aging Sun-like stars demonstrates that they likely eat their closest planets.
eos.org
December 2, 2025 at 4:42 PM
I have eaten
the planets
that were in
the inner solar system
and which
you were probably
saving
for living on
Forgive me
they were delicious
so crunchy
and so warm
the planets
that were in
the inner solar system
and which
you were probably
saving
for living on
Forgive me
they were delicious
so crunchy
and so warm
Reposted by Kelly Lepo
Beautiful!
On Mars, dust grains are ~ the same size as visible light wavelengths, so they scatter red light away (Mie scattering) and let blue through near the Sun.
On Earth, air molecules are far smaller, scatter blue away (Rayleigh) and leave red.
Same physics, inverted colors!
🔭 🧪 #science
On Mars, dust grains are ~ the same size as visible light wavelengths, so they scatter red light away (Mie scattering) and let blue through near the Sun.
On Earth, air molecules are far smaller, scatter blue away (Rayleigh) and leave red.
Same physics, inverted colors!
🔭 🧪 #science
My artwork of a Sunset on Mars. Dust and small particles suspended in the Martian atmosphere scatter light in the direction of the Sun forward. This creates a blue halo around the setting Sun, rendering a Martian landscape quite different from its terrestrial equivalent.
#ArtAdventCalendar
#SciArt
#ArtAdventCalendar
#SciArt
December 1, 2025 at 2:54 PM
Beautiful!
On Mars, dust grains are ~ the same size as visible light wavelengths, so they scatter red light away (Mie scattering) and let blue through near the Sun.
On Earth, air molecules are far smaller, scatter blue away (Rayleigh) and leave red.
Same physics, inverted colors!
🔭 🧪 #science
On Mars, dust grains are ~ the same size as visible light wavelengths, so they scatter red light away (Mie scattering) and let blue through near the Sun.
On Earth, air molecules are far smaller, scatter blue away (Rayleigh) and leave red.
Same physics, inverted colors!
🔭 🧪 #science
Reposted by Kelly Lepo
Very excited to share the NASA/ESA/STScI press release of our team's work on Apep! It's a terrific writeup, complete with a brand new beautiful visualisation of the nebula geometry.
1/? ⚛️🔭🧪
science.nasa.gov/missions/web...
1/? ⚛️🔭🧪
science.nasa.gov/missions/web...
Webb First to Show 4 Dust Shells 'Spiraling' Apep, Limits Long Orbit - NASA Science
NASA’s James Webb Space Telescope has delivered a first of its kind: a crisp mid-infrared image of a system of four serpentine spirals of dust, one expanding
science.nasa.gov
November 19, 2025 at 10:08 PM
Very excited to share the NASA/ESA/STScI press release of our team's work on Apep! It's a terrific writeup, complete with a brand new beautiful visualisation of the nebula geometry.
1/? ⚛️🔭🧪
science.nasa.gov/missions/web...
1/? ⚛️🔭🧪
science.nasa.gov/missions/web...
Reposted by Kelly Lepo
Here are the #I/ATLAS releases from varied NASA/ESA missions. Having worked with such telescope & spacecraft data for 40 years, my perspective is: no surprises. It's a comet; its differences from Solar System comets are intriguing but every comet is different! science.nasa.gov/solar-system...
November 19, 2025 at 8:42 PM
Here are the #I/ATLAS releases from varied NASA/ESA missions. Having worked with such telescope & spacecraft data for 40 years, my perspective is: no surprises. It's a comet; its differences from Solar System comets are intriguing but every comet is different! science.nasa.gov/solar-system...
Reposted by Kelly Lepo
Just want to emphasize here that this is an image of an INTERSTELLAR COMET taken by a camera orbiting MARS. Space is so cool!
NASA's pix of the interstellar comet 3I/ATLAS are now up science.nasa.gov/solar-system...
This is the HiRISE/MRO image ⬇️
This is the HiRISE/MRO image ⬇️
November 19, 2025 at 8:30 PM
Just want to emphasize here that this is an image of an INTERSTELLAR COMET taken by a camera orbiting MARS. Space is so cool!
I'm glad this is finally out after the government shutdown!
JWST's images of dusty, spiraling shells around Wolf-Rayet star binaries are my favorite.
JWST's images of dusty, spiraling shells around Wolf-Rayet star binaries are my favorite.
Three #NASAWebb discoveries in ONE! Webb shows there are FOUR dust shells (only one was previously seen), allowing researchers to narrow the stars’ orbit of one another to a LONG 190 years. Plus, they confirmed a third star is part of the “party”: https://bit.ly/4n1tpas 🔭 🧪
November 19, 2025 at 4:14 PM
I'm glad this is finally out after the government shutdown!
JWST's images of dusty, spiraling shells around Wolf-Rayet star binaries are my favorite.
JWST's images of dusty, spiraling shells around Wolf-Rayet star binaries are my favorite.
Reposted by Kelly Lepo
NASA will host a live event at 3 p.m. EST, Wednesday, Nov. 19, to share imagery of the interstellar comet 3I/ATLAS collected by a number of the agency’s missions. The event will take place at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. www.nasa.gov/news-release... ☄️🔭
NASA to Share Comet 3I/ATLAS Images From Spacecraft, Telescopes - NASA
NASA will host a live event at 3 p.m. EST, Wednesday, Nov. 19, to share imagery of the interstellar comet 3I/ATLAS collected by a number of the agency’s
www.nasa.gov
November 17, 2025 at 10:04 PM
NASA will host a live event at 3 p.m. EST, Wednesday, Nov. 19, to share imagery of the interstellar comet 3I/ATLAS collected by a number of the agency’s missions. The event will take place at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. www.nasa.gov/news-release... ☄️🔭
Reposted by Kelly Lepo
Well, here's some very exciting news!
I've been wanting to share this for a few months, but had to wait for the pre-print to drop.
A NEW GLITCH ON A MILLISECOND PULSAR HAS BEEN OBSERVED!
These events are extremely rare - only two others since MSPs discovered.
🔭🧪📡
I've been wanting to share this for a few months, but had to wait for the pre-print to drop.
A NEW GLITCH ON A MILLISECOND PULSAR HAS BEEN OBSERVED!
These events are extremely rare - only two others since MSPs discovered.
🔭🧪📡
For only the third time ever, a glitch event has been observed on a millisecond #pulsar.
@rami.spaceaustralia.com chats with lead author and PhD candidate Bhavnesh Bhat about the significance of this important, yet rare, event.
www.spaceaustralia.com/news/new-gli...
#SpaceAustralia
📸 NASA SVS
@rami.spaceaustralia.com chats with lead author and PhD candidate Bhavnesh Bhat about the significance of this important, yet rare, event.
www.spaceaustralia.com/news/new-gli...
#SpaceAustralia
📸 NASA SVS
November 17, 2025 at 8:05 PM
Well, here's some very exciting news!
I've been wanting to share this for a few months, but had to wait for the pre-print to drop.
A NEW GLITCH ON A MILLISECOND PULSAR HAS BEEN OBSERVED!
These events are extremely rare - only two others since MSPs discovered.
🔭🧪📡
I've been wanting to share this for a few months, but had to wait for the pre-print to drop.
A NEW GLITCH ON A MILLISECOND PULSAR HAS BEEN OBSERVED!
These events are extremely rare - only two others since MSPs discovered.
🔭🧪📡
Reposted by Kelly Lepo
My entire timeline rn.
November 12, 2025 at 1:41 AM
My entire timeline rn.
Reposted by Kelly Lepo
Submit them to Aurorasaurus!!! They're an NSF funded project out of University of New Mexico that takes crowdsourced aurora observations for research purposes:
www.aurorasaurus.org
www.aurorasaurus.org
Aurorasaurus - Reporting Auroras from the Ground Up
Friends, see my real-time #aurora report on the aurorasaurus.org map! Follow us on www.facebook.com/aurorasaurus.org. Reporting #northernlights and #citizenscience from the ground up since 2012!
www.aurorasaurus.org
November 12, 2025 at 3:25 AM
Submit them to Aurorasaurus!!! They're an NSF funded project out of University of New Mexico that takes crowdsourced aurora observations for research purposes:
www.aurorasaurus.org
www.aurorasaurus.org