SETI Institute

Photo of theoretical physicist Brian Greene in front of a blackboard full of differential equations.

One of the best-known proponents of string theory, Brian Greene, explains why it remains the most comprehensive theory for understanding the fundamental laws of nature. But can it even be tested? It’s Skeptic Check: String Theory on @bipisci.bsky.social. 🧪

Listen here: buff.ly/SOmv0qH

#podcast

Their goal was straightforward: to establish whether 3I/ATLAS could be seen in radio waves. And their findings now confirm: it behaves like a comet, and not a technological artefact broadcasting radio signals.

Learn more: www.ru.ac.za/latestnews/r...

At the centre of it: MeerKAT, one of the world’s most sensitive radio telescopes and a research team drawn from the University of Cape Town, SARAO, Rhodes University, Sweden’s KTH Royal Institute of Technology, and the Breakthrough Listen initiative.

The internet promptly filled the gap with theories ranging from the plausible to the eccentric. However, while the speculation churned, a quieter, methodical effort began to take shape in South Africa.

When a faint, fast-moving speck named 3I/ATLAS slipped into view earlier this year, it carried more than a whiff of cosmic intrigue. Only two other confirmed interstellar objects have ever wandered through our Solar System, and both left scientists with more questions than answers. 🧪 🔭 👩‍🔬

CORRECTION: Applications open on November 20, 2025, and must be submitted by January 16, 2026.

Moss Can Survive the Harsh Conditions of Space A months-long sojourn outside the International Space Station didn't phase these plants.

A team demonstrated that more than 80% of moss spores left on the outside of the ISS for nine months and brought back to Earth germinated normally. The findings confirm that moss spores, already known to be hardy, handily survive the stresses of near-Earth orbit. 🧪 👩‍🔬

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Deception Island | Copernicus On 17 March 2023, one of the Copernicus Sentinel-2 satellites captured this rare cloud-free image of  Deception Island.

Learn more: www.copernicus.eu/en/media/ima...

This caldera creates a unique, sheltered harbour that has previously served as a natural haven for whaling and sealing ships.

Moreover, the caldera's shape provides a protective barrier from strong winds and currents, creating a microclimate that supports a rich and diverse ecosystem.

It has long been the focus of intense interest from both tourists and researchers because of its remarkable geology and unique ecological characteristics.

The island boasts a horseshoe-shaped caldera, a distinguishing feature formed by a large volcanic eruption approximately 10,000 years ago.

A cloud-free satellite image of Deception Island in the South Shetland Islands of Antarctica. The island forms an almost-closed horseshoe with a small opening near the bottom right of the image. Two sets of snow-covered peaks line the bottom and right of the horseshoe.

#PPOD: On 17 March 2023, one of the Copernicus Sentinel-2 satellites captured this rare cloud-free image of Deception Island, an active volcanic caldera located in the South Shetland Islands of Antarctica. Credit: European Union, Copernicus Sentinel-2 imagery 🧪

Agata Zupanska Principal Investigator and Research Scientist

Not Just Aliens is the SETI Institute’s weekly series featuring scientists exploring astrobiology, heliophysics, planetary science, and more — expanding the search for life beyond Earth. And sometimes, we feature scientists looking for technosignatures!

Learn more: www.seti.org/people/agata...

Dr. Zupanska is particularly interested in spaceflight microgravity and uses the International Space Station laboratory for her research experiments. She also conducts experiments with high-energy ion beams to explore how plants can withstand cosmic ionizing radiation that pervades deep space.

Text: #notjustaliens. Agata Zupanska, Molecular Biology. Background: Starry night sky. Inset: Photo of Agata Zupanska.

Text: Dr. Agata Zupanska brings a biologist’s perspective to the quest for understanding life. She tests the limits of terrestrial plant life and works on preparing plants for deep space human missions, all with a goal to advance deep space exploration. Background: Starry night sky with graphics of a star and exoplanets in front of it.

Text: Dr. Zupanska is particularly interested in spaceflight microgravity and uses the International Space Station laboratory for her research experiments. She also conducts experiments with high-energy ion beams at the NASA Space Radiation Laboratory, at the Brookhaven National Laboratory, to explore how plants can withstand cosmic ionizing radiation that pervades deep space. Background: Starry night sky with graphics of a star and exoplanets.

SETI Institute logo. Graphics: (top) Black hole. (bottom) radio telescope dishes at the Allen Telescope Array. Background: Starry night sky.

Dr. Agata Zupanska brings a biologist’s perspective to the quest for understanding life. She tests the limits of terrestrial plant life and works on preparing plants for deep space human missions, all with a goal to advance deep space exploration. 🧪 🔭 👩‍🔬

SETI Institute Invites Applications for the 2026 Mino Postdoctoral Fellowship

Applications open on November 20, 2025, and must be submitted by May 1, 2026.

To learn more and apply: www.seti.org/news/seti-in...

SETI Institute logo. Text: SETI Institute invites applications for the 2026 Mino Postdoctoral Fellowship. Background: Photo of physicist Minoru Freund standing in front of a spacecraft model.

PRESS RELEASE:
The SETI Institute is pleased to open the call for applications for the 2026 Mino Postdoctoral Fellowship. This research program offers an exceptional opportunity for talented early-career scientists worldwide to contribute significant advances in several fields. 🧪 🔭 👩‍🔬

The Moon that Could Support Life: What Cassini Discovered Beneath the Ice of Enceladus Join host Beth Johnson for a fascinating episode of SETI Live, featuring planetary scientists Dr Georgina Miles and Dr Carly Howett from the University of Ox...

WATCH LIVE: youtube.com/live/fDf0VQ_...

SETI Live record button logo. Text: The Moon That Could Support Life with Beth Johnson, Georgina Miles, and Carly Howett. Background: Artist's representation of Enceladus looking back at the Sun, using Cassini imagery of the moon. Inset: Photos of Georgina Miles and Carly Howett.

Next #SETILive: The Moon that Could Support Life
TODAY, 20 November, 11 am PST

Join @planetarypan.bsky.social and planetary scientists Dr Georgina Miles and Dr Carly Howett (University of Oxford) to discuss their latest study, which shows that Enceladus may harbor a stable subsurface ocean. 🧪 🔭 👩‍🔬

Credit: ESA/TGO/CaSSIS

Learn more: www.esa.int/ESA_Multimed...

The smooth appearance of the crater is consistent with other features in the region, which have evidence of a water-ice history. Zooming into the crater, it is possible to see streaks on the walls of the crater, showing evidence of landslides, and ripples sculpted by the wind.

This view shows a crater approximately 8 kilometres in diameter with material ejected in a manner that scientists believe suggests the presence of water ice. When the asteroid hit this region of Mars, the water ice melted, and a mix of liquid water and dust rock was propelled from the top layers.

This remnant of an ancient impact is just one of the many scars asteroids have inflicted upon the Red Planet. Water, volcanoes, and impacts from asteroids shaped the Martian surface in the ancient past. Mars is currently a cold, dry desert.

A smooth sided crater takes up the majority of this image, taken from space, of the surface of Mars. Ejecta from the impact can be seen as lighter colored dust around the rim of the crater and even in some smaller craters to the left and below the main one. Dark streaks down the inside cliff walls could be evidence of water ice under the surface. The bottom of the crater seems to be almost flat.

#PPOD: A vast cavity on the Red Planet looks back at ExoMars Trace Gas Orbiter (TGO) with an icy stare. The crater is located in Utopia Planitia, the largest known impact basin in the Solar System, with a diameter of roughly 3,300 km, or twice the size of Earth’s Sahara Desert from north to south. 🧪

NASA Webb 'Pierces' Bullet Cluster, Refines Its Mass - NASA Science NASA’s James Webb Space Telescope recently zeroed in on the Bullet Cluster — delivering highly detailed images that show a greater abundance of extremely

Learn more: science.nasa.gov/missions/web...

The Bullet Cluster is unusual in that the intracluster gas and dark matter are separated, offering further evidence in support of dark matter.

Credit: Image: NASA, ESA, CSA, STScI, CXC; Science: James Jee (Yonsei University, UC Davis), Sangjun Cha (Yonsei University), Kyle Finner (Caltech/IPAC)

The blue represents the dark matter, which was precisely mapped by researchers with JWST's detailed imaging. Usually, gas, dust, stars, and dark matter are combined into galaxies, even when they are gravitationally bound within larger groups known as galaxy clusters.

Landscape image full of galaxies, featuring in particular, two galaxy clusters that make up a region known as the Bullet Cluster. At the center is a pink cloud that represents X-rays mapped by Chandra. To either side are blueish "clouds" that are actually the mapped areas of dark matter as determined by JWST's infrared observations.

#PPOD: This is the central region of the Bullet Cluster, comprised of two massive galaxy clusters. The vast number of galaxies and foreground stars in the image was captured by NASA’s JWST in near-infrared light. Glowing, hot X-rays captured by NASA’s Chandra X-ray Observatory appear in pink. 🧪 🔭

This Microbe Breathes Two Ways! The Bacteria That Challenge Biochemistry

In a recent SETI Live episode, Dr. Eric Boyd, microbial geochemist at Montana State University, joined SETI Institute communications specialist @planetarypan.bsky.social to discuss his team’s groundbreaking findings.

Learn more: www.seti.org/news/this-mi...

A recent discovery from Yellowstone National Park has redefined one of biology’s most basic assumptions: that a cell must “choose” between using oxygen or other chemicals to breathe. 🧪 👩‍🔬

Credit: NASA, ESA, JPL, ISS, Cassini Imaging Team; Processing: Fernando Garcia Navarro