Since its discovery on 1 July 2025 by the Asteroid Terrestrial-impact Last Alert System (ATLAS), the object known as 3I/ATLAS has captured the popular imagination, being only the third known […]
3I/ATLAS
Europa Clipper Instrument Uniquely Observed Interstellar Comet 3I/ATLAS
SwRI-led Ultraviolet Spectrograph viewed 3I/ATLAS both when and where most other assets could not.
University of Hawaii 88-inch Telescope Observations of the Interstellar Comet 3I/ATLAS: Spectrophotometric Blue-Sensitive Spectral Time Series Spanning Two Months from Discovery
Interstellar objects are the ejected building blocks of other solar systems. As such, they enable the acquisition of otherwise inaccessible information about nascent extrasolar systems.
XMM-Newton Sees Interstellar Comet 3I/ATLAS in X-ray Light
The European Space Agency’s X-ray space observatory XMM-Newton observed interstellar comet 3I/ATLAS on 3 December for around 20 hours. During that time, the comet was about 282–285 million km from […]
CH3OH and HCN in Interstellar Comet 3I/ATLAS Mapped with the ALMA Atacama Compact Array: Distinct Outgassing Behaviors and a Remarkably High CH3OH/HCN Production Rate Ratio
We report the detection of methanol (CH3OH) toward interstellar comet 3I/ATLAS using the Atacama Compact Array of the Atacama Large Millimeter/Submillimeter Array (ALMA) on UT 2025 August 28, September 18 […]
SPHEREx Pre-Perihelion Mapping of H2O, CO2, and CO in Interstellar Object 3I/ATLAS
From 01- to 15-Aug-2025 UT, the SPHEREx spacecraft observed interstellar object 3I/ATLAS. Using R=40-130 spectrophotometry at λ=0.7-5μm, light curves, spectra, and imaging of 3I were obtained.
SwRI Researchers Use PUNCH To Track Interstellar Comet 3I/ATLAS
A Southwest Research Institute (SwRI) project is using data from NASA’s Polarimeter to Unify the Corona and Heliosphere (PUNCH) spacecraft to track the interstellar comet 3I/ATLAS.
Hubble Space Telescope Revisits Interstellar Comet 3I/ATLAS
NASA’s Hubble Space Telescope reobserved interstellar comet 3I/ATLAS Nov. 30, with its Wide Field Camera 3 instrument. At the time, the comet was about 178 million miles (286 million kilometers) […]
Interstellar Comet 3I/ATLAS Shows Activity In ESA Juice Navigation Camera Image
During November 2025, ESA’s Jupiter Icy Moons Explorer (Juice) used five of its science instruments to observe 3I/ATLAS. The instruments collected information about how the comet is behaving and what […]
Spectrophotometric Evidence For A Metal-bearing, Carbonaceous, and Pristine Interstellar Comet 3I/ATLAS
3I/ATLAS is only the second confirmed cometary object known to enter the Solar System from interstellar space.
