Astronomers Spot the First Moon Outside Our Solar System

🌙 First exomoon candidate ever detected

🌋 Juno reveals Io's volcanic heat runs deep

👽 SETI search expands past the "water hole"

☢️ NASA's nuclear Mars mission gets a price tag

🕳️ JWST spots a filament feeding a distant black hole

European Southern Observatory astronomers led by Kevin Hoy used the Very Large Telescope's CRIRES+ instrument to detect what may be the first confirmed exomoon, orbiting a brown dwarf in the CD-35 2722 system rather than a planet.

The team applied the radial velocity method — the same technique used to find the first exoplanet around a Sun-like star — to detect wobbles in the brown dwarf caused by the orbiting object, which is at least as massive as Jupiter.

Hoy describes the system as "super weird" compared to our own, noting the object is clearly massive enough to be a planet but orbits a brown dwarf instead of a star, blurring the traditional lines between planets and moons.

NASA's Juno spacecraft used its Microwave Radiometer instrument during two close flybys to take the first-ever subsurface temperature measurements of Io, the most volcanically active body in the solar system.

Data revealed the temperature rises more than 40 degrees Fahrenheit within just a few feet of the surface, a gradient far steeper than solar heating alone could explain, and found large stretches of surprisingly smooth, low-density terrain.

Principal investigator Scott Bolton says the technique could also help study terrestrial volcanoes, since a similar instrument pointed at an Earth volcano might reveal a comparable subsurface heat signature.

University of Manchester researcher Louisa Mason conducted the first-ever SETI survey using the Atacama Large Millimeter/submillimeter Array (ALMA), searching archived data at radio frequencies far outside the traditional "water hole" band astronomers have focused on for decades.

Although Mason found no candidate technosignatures in the frequencies she examined, her method of estimating "stellar bycatch" with a galactic model instead of star catalogs increased the estimated stars surveyed in one past study from 288,000 to more than 6.1 million.

Mason says the null result doesn't mean intelligent life doesn't exist, only that no signal turned up in the narrow ranges studied, and hopes the work pushes future surveys to search a wider swath of the spectrum.

NASA confirmed early cost estimates for Space Reactor-1 Freedom, its planned nuclear-powered mission to Mars, at approximately $2.1 billion — a figure that excludes the SkyFall science payload the spacecraft would carry.

According to a document sent to Congress and reviewed by Politico, the agency plans to spend $640 million in fiscal 2026, ramping to $890 million in 2027, before dropping to $415 million in 2028 and $180 million in 2029 ahead of a targeted late-2028 launch.

NASA says pairing the launch and Mars transportation capability with the reactor mission supports its goal of lowering costs while focusing on near-term science opportunities, even as the agency juggles competing lunar priorities.

Astronomers using JWST's NIRSpec instrument as part of the BlackTHUNDER program discovered a 12-kiloparsec-long filament of multiple galaxies surrounding GN-77652, a compact black hole spotted just over a billion years after the Big Bang.

The five sources along the filament span a wide range of stellar masses, metallicities, and star formation rates, and emission-line diagnostics hint that a second, previously unknown black hole may be lurking in one of the more massive nearby galaxies.

Lead author Giulia Tozzi and colleagues estimate the whole cluster of galaxies is likely to merge into a single massive galaxy within 150 to 440 million years, suggesting the black hole's unusual compact appearance may just be a brief evolutionary phase.