Carl Sagan Institute
@carlsaganinstitute.bsky.social
Interdisciplinary research team at Cornell University, following Carl Sagan's legacy by building the tools to find life in the Universe.
https://carlsaganinstitute.cornell.edu/
https://carlsaganinstitute.cornell.edu/
Alpha’s mission sends the first holographic images to space, tests tiny ChipSat technology, demonstrates one of the smallest—and first free-flying—light sail designs, and proves that low-cost light sailing is a possible path for a variety of future missions.
Ad astra, Alpha Cubesat ✨
Ad astra, Alpha Cubesat ✨
December 5, 2025 at 6:55 PM
Alpha’s mission sends the first holographic images to space, tests tiny ChipSat technology, demonstrates one of the smallest—and first free-flying—light sail designs, and proves that low-cost light sailing is a possible path for a variety of future missions.
Ad astra, Alpha Cubesat ✨
Ad astra, Alpha Cubesat ✨
Regardless of its short lifespan, Alpha CubeSat has demonstrated the tenacity of hundreds of undergraduate students, equipped with a toolkit of nothing more than hobbyist electronics and their drive to help build the future of spaceflight.
December 5, 2025 at 6:55 PM
Regardless of its short lifespan, Alpha CubeSat has demonstrated the tenacity of hundreds of undergraduate students, equipped with a toolkit of nothing more than hobbyist electronics and their drive to help build the future of spaceflight.
Drag is expected to pull the light sail out of orbit quicker than the CubeSat, so this may explain the silence. The sail was only projected to live for a few days, and the ChipSats are much smaller/harder to pick up than the CubeSat—so it's an incredible feat that we heard from them at all!
December 5, 2025 at 6:55 PM
Drag is expected to pull the light sail out of orbit quicker than the CubeSat, so this may explain the silence. The sail was only projected to live for a few days, and the ChipSats are much smaller/harder to pick up than the CubeSat—so it's an incredible feat that we heard from them at all!
The CubeSat is currently alive and transmitting. You can see the data update every few hours here: alphacubesat.cornell.edu/dashboard.html. There's also a link to the light sail's ChipSat signals (although he team hasn't heard from the light sail's ChipSats recently).
December 5, 2025 at 6:55 PM
The CubeSat is currently alive and transmitting. You can see the data update every few hours here: alphacubesat.cornell.edu/dashboard.html. There's also a link to the light sail's ChipSat signals (although he team hasn't heard from the light sail's ChipSats recently).
Just as suddenly as it fell silent, the spacecraft spoke again! Alpha heard the command and deployed the light sail successfully, and the tiny radio transmitters on the light sail (contained in four credit card-sized computers called “ChipSats”) began to send their own separate signals down, too.
December 5, 2025 at 6:55 PM
Just as suddenly as it fell silent, the spacecraft spoke again! Alpha heard the command and deployed the light sail successfully, and the tiny radio transmitters on the light sail (contained in four credit card-sized computers called “ChipSats”) began to send their own separate signals down, too.
This video from the International Space Station on December 2nd shows four CubeSats (small cube-shaped spacecraft), one of which is Alpha, holding its light sail inside. Tumbling through space at thousands of miles per hour, Alpha sent radio signals soon after launch… then fell silent.
December 5, 2025 at 6:55 PM
This video from the International Space Station on December 2nd shows four CubeSats (small cube-shaped spacecraft), one of which is Alpha, holding its light sail inside. Tumbling through space at thousands of miles per hour, Alpha sent radio signals soon after launch… then fell silent.
CONGRATULATIONS to CSI fellow Dr. Josh Umansky-Castro and the whole Alpha CubeSat team: they've successfully deployed the first-ever light sail to “free fly” in space (disconnect from its spacecraft)!
Read the story of its first few days in space below!
🔭
Read the story of its first few days in space below!
🔭
December 5, 2025 at 6:55 PM
CONGRATULATIONS to CSI fellow Dr. Josh Umansky-Castro and the whole Alpha CubeSat team: they've successfully deployed the first-ever light sail to “free fly” in space (disconnect from its spacecraft)!
Read the story of its first few days in space below!
🔭
Read the story of its first few days in space below!
🔭
If alien life fluoresces at the same wavelengths we’re familiar with—and if clouds don’t block too much of our view—then with upcoming telescopes like the Habitable Worlds Observatory, it may be challenging, but possible, to find glow-in-the-dark signs of life on small, rocky exoplanets!
October 31, 2025 at 6:14 PM
If alien life fluoresces at the same wavelengths we’re familiar with—and if clouds don’t block too much of our view—then with upcoming telescopes like the Habitable Worlds Observatory, it may be challenging, but possible, to find glow-in-the-dark signs of life on small, rocky exoplanets!
In a follow-up paper, the authors also found that biofluorescence could be useful around cooler red dwarf stars that have ultraviolet “flares"—high-energy bursts that life would need to protect itself from.
Paper 1: academic.oup.com/mnras/articl...
Follow-up: academic.oup.com/mnras/articl...
Paper 1: academic.oup.com/mnras/articl...
Follow-up: academic.oup.com/mnras/articl...
October 31, 2025 at 6:14 PM
In a follow-up paper, the authors also found that biofluorescence could be useful around cooler red dwarf stars that have ultraviolet “flares"—high-energy bursts that life would need to protect itself from.
Paper 1: academic.oup.com/mnras/articl...
Follow-up: academic.oup.com/mnras/articl...
Paper 1: academic.oup.com/mnras/articl...
Follow-up: academic.oup.com/mnras/articl...
O’Malley-James & Kaltenegger found that if a planet around a bluer F-type star was covered in 70% ocean and 30% lifeforms such as strongly biofluorescent coral on Earth, then we could receive roughly 10% more light at the wavelengths that these organisms emit (see table below for more scenarios)
October 31, 2025 at 6:14 PM
O’Malley-James & Kaltenegger found that if a planet around a bluer F-type star was covered in 70% ocean and 30% lifeforms such as strongly biofluorescent coral on Earth, then we could receive roughly 10% more light at the wavelengths that these organisms emit (see table below for more scenarios)
On alien planets orbiting bluer stars, where more “sunscreen” is needed, biofluorescence might make up a larger fraction of the light we’d receive in our telescopes. CSI researchers O’Malley-James & Kaltenegger examined biofluorescent life on Earth to determine what glowing colors of light we’d see.
October 31, 2025 at 6:14 PM
On alien planets orbiting bluer stars, where more “sunscreen” is needed, biofluorescence might make up a larger fraction of the light we’d receive in our telescopes. CSI researchers O’Malley-James & Kaltenegger examined biofluorescent life on Earth to determine what glowing colors of light we’d see.
You may be wondering—how bright is this “biofluorescence” anyway? Earth is covered in plants, and many of them emit a small amount of fluorescent light. However, this is just a fraction of a percent of all the green light we see reflected. (More info in Sagan’s Galileo study: tinyurl.com/yc2xtr43)
October 31, 2025 at 6:14 PM
You may be wondering—how bright is this “biofluorescence” anyway? Earth is covered in plants, and many of them emit a small amount of fluorescent light. However, this is just a fraction of a percent of all the green light we see reflected. (More info in Sagan’s Galileo study: tinyurl.com/yc2xtr43)
Happy Halloween! ✨ 👻 🎃 Jack-o’-lanterns aren’t the only signs of life that glow in the dark. Some organisms on Earth do, too. Would a distant planet full of glow-in-the-dark aliens be detectable to our telescopes? 🔭
October 31, 2025 at 6:14 PM
Happy Halloween! ✨ 👻 🎃 Jack-o’-lanterns aren’t the only signs of life that glow in the dark. Some organisms on Earth do, too. Would a distant planet full of glow-in-the-dark aliens be detectable to our telescopes? 🔭
The star will have to treat its planet kindly, lest it strip away the planet’s atmosphere, or heat the planet so intensely it becomes a “lava world.” Even if the planet avoids these extremes and organisms manage to thrive, the world those organisms call home may look quite different from ours.
September 21, 2025 at 6:43 PM
The star will have to treat its planet kindly, lest it strip away the planet’s atmosphere, or heat the planet so intensely it becomes a “lava world.” Even if the planet avoids these extremes and organisms manage to thrive, the world those organisms call home may look quite different from ours.
Some of these planets—the more sedate, less extreme ones—have a chance at hosting life. They’ll need to be not too far, not too close, but just the right distance from their host star: in the “Goldilocks” or “habitable” zone where liquid water could exist on a planet's surface.
September 21, 2025 at 6:43 PM
Some of these planets—the more sedate, less extreme ones—have a chance at hosting life. They’ll need to be not too far, not too close, but just the right distance from their host star: in the “Goldilocks” or “habitable” zone where liquid water could exist on a planet's surface.
There is a planet that takes 49 minutes to orbit its pulsar, in a pirouette too tight to ever allow for life; there are red-hot planets where gems may fall from clouds of metal and deep blue dots where glass may rain sideways.
September 21, 2025 at 6:43 PM
There is a planet that takes 49 minutes to orbit its pulsar, in a pirouette too tight to ever allow for life; there are red-hot planets where gems may fall from clouds of metal and deep blue dots where glass may rain sideways.
There are exoplanets that see two Suns in their skies, even three Suns; there are “rogue planets,” likely ejected from the disks of young stars, that shoot through an endless night; there is a planet that takes one million years to orbit its star;
September 21, 2025 at 6:43 PM
There are exoplanets that see two Suns in their skies, even three Suns; there are “rogue planets,” likely ejected from the disks of young stars, that shoot through an endless night; there is a planet that takes one million years to orbit its star;
6000 exoplanets. 🔭
We’ve found worlds orbiting all sorts of stars, from tiny, slow-burning reds to fast-living blue-whites to middle-of-the-road, prime-of-their-life yellows like our own...
We’ve found worlds orbiting all sorts of stars, from tiny, slow-burning reds to fast-living blue-whites to middle-of-the-road, prime-of-their-life yellows like our own...
September 21, 2025 at 6:43 PM
6000 exoplanets. 🔭
We’ve found worlds orbiting all sorts of stars, from tiny, slow-burning reds to fast-living blue-whites to middle-of-the-road, prime-of-their-life yellows like our own...
We’ve found worlds orbiting all sorts of stars, from tiny, slow-burning reds to fast-living blue-whites to middle-of-the-road, prime-of-their-life yellows like our own...
Just over five hours until Cornell's Alpha CubeSat launches on its way to the International Space Station! Learn more about the satellite, its lightsail, and its holograms at alphacubesat.cornell.edu, and tune into the livestream of the rocket launch there!
September 14, 2025 at 4:27 PM
Just over five hours until Cornell's Alpha CubeSat launches on its way to the International Space Station! Learn more about the satellite, its lightsail, and its holograms at alphacubesat.cornell.edu, and tune into the livestream of the rocket launch there!
Congratulations to project lead/CSI engineer Josh Umanksy-Castro, project advisor/CSI fellow Mason Peck, and to all the Cornell students who poured their heart into this mission!
September 13, 2025 at 7:09 PM
Congratulations to project lead/CSI engineer Josh Umanksy-Castro, project advisor/CSI fellow Mason Peck, and to all the Cornell students who poured their heart into this mission!
The NG-23 ISS commercial resupply mission launch is scheduled for Sunday 9/14 at 6:11pm EST with a backup opportunity on Monday 9/15 at 5:49pm. Alpha will ride to the International Space Station, then patiently wait for its turn to launch off the station and into space in mid-November.
September 13, 2025 at 7:09 PM
The NG-23 ISS commercial resupply mission launch is scheduled for Sunday 9/14 at 6:11pm EST with a backup opportunity on Monday 9/15 at 5:49pm. Alpha will ride to the International Space Station, then patiently wait for its turn to launch off the station and into space in mid-November.
A large group of Cornell students, alumni, family and friends are traveling to Cape Canaveral this weekend to view the launch! We invite you to join us by tuning into the livestream, linked at alphacubesat.cornell.edu.
September 13, 2025 at 7:09 PM
A large group of Cornell students, alumni, family and friends are traveling to Cape Canaveral this weekend to view the launch! We invite you to join us by tuning into the livestream, linked at alphacubesat.cornell.edu.
After 9 years and over 100 students, Cornell's Alpha CubeSat mission is launching to space TOMORROW! This small cube-shaped satellite will test the deployment of the first-ever free-flying light sail in low Earth orbit, a stepping stone towards laser sailing to the stars. 🔭
alphacubesat.cornell.edu
alphacubesat.cornell.edu
September 13, 2025 at 7:09 PM
After 9 years and over 100 students, Cornell's Alpha CubeSat mission is launching to space TOMORROW! This small cube-shaped satellite will test the deployment of the first-ever free-flying light sail in low Earth orbit, a stepping stone towards laser sailing to the stars. 🔭
alphacubesat.cornell.edu
alphacubesat.cornell.edu
For now, CSI researchers will construct better and better models for TRAPPIST-1 e's busy host star, until the day we can fully disentangle little planets from jumpy starlight!
Read more: carlsaganinstitute.cornell.edu/news/there-w...
(Papers also linked in article)!
Read more: carlsaganinstitute.cornell.edu/news/there-w...
(Papers also linked in article)!
September 13, 2025 at 12:04 AM
For now, CSI researchers will construct better and better models for TRAPPIST-1 e's busy host star, until the day we can fully disentangle little planets from jumpy starlight!
Read more: carlsaganinstitute.cornell.edu/news/there-w...
(Papers also linked in article)!
Read more: carlsaganinstitute.cornell.edu/news/there-w...
(Papers also linked in article)!
But even noisy data lets us rule out a few possibilities—models that would cause much larger dips than the ones in the graph. TRAPPIST-1 e is unlikely to have a huge hydrogen atmosphere, nor a huge carbon dioxide atmosphere like Venus, which traps enough heat to melt lead.
September 13, 2025 at 12:04 AM
But even noisy data lets us rule out a few possibilities—models that would cause much larger dips than the ones in the graph. TRAPPIST-1 e is unlikely to have a huge hydrogen atmosphere, nor a huge carbon dioxide atmosphere like Venus, which traps enough heat to melt lead.