cometary-science

Is it possible for us to send a spaceship to Comet 3I/ATLAS to collect samples of its gas, dust, and surface and bring them back to Earth for analysis? Raymond Tanguay It would be great to get a spacecraft to an interstellar object to see it up close and to sample what it is made of. Continue reading "Could we send a spaceship to Comet 3I/ATLAS to collect samples and bring them back for analysis?…

In September 1999, the Lincoln Near Earth Asteroid Research (LINEAR) project discovered a comet – Comet C/1999 S4, or Comet LINEAR – on a course for the Sun. Its unusual behavior drew attention: By July 5-7 of the following year, the Hubble Space Telescope had watched a piece of its crust blow off as if Continue reading "July 26, 2000: Comet LINEAR disintegrates" The post July 26, 2000: Comet LIN…

Comets are known for providing breathtaking observations of their long and shiny tails when they travel too close to the Sun. This happens because comets are made of ice and primarily orbit far from the Sun, but as their icy core heats up it evaporates, resulting in the aforementioned breathtaking observations. But while evaporating comets […] The post Spin-reversing comet may face self-destructi…

This periodic visitor is now bright enough to see in binoculars from a dark sky. We also report on a bright supernova in Ursa Major. The post Comet 10P/Tempel Brightens, Sets Sail South appeared first on Sky & Telescope .

Nature Astronomy, Published online: 21 July 2026; doi:10.1038/s41550-026-02912-8 Based on activity inferred from observed comet-like nongravitational acceleration, we report the detection of a cometary tail on a near-Earth object that was previously classified as inactive. This finding demonstrates that nongravitational accelerations can be used to infer the outgassing of ices on covertly ‘inacti…

Our ability to track and visualize small rocks in space is still improving. And occasionally we’ll find a space rock that will remind us of that fact. One such rock is detailed in a new paper, led by Davide Farnocchia of NASA’s Jet Propulsion Laboratory, and recently published in Nature Astronomy, where the research team discovered what they thought was a normal, run of the mill asteroid, was act…

Chris Schur, taken from Happy Jack, Arizona Comet 10P/Tempel 2’s needle-thin dust trail stands out starkly in this image captured earlier this month as the comet was crossing Capricornus, heading toward its Aug. 2 perihelion. This trail of dust is not a traditional comet’s tail, directly blown out by the Sun — rather, it’s dust Continue reading "Tempel’s trail strengthens" The post Tempel’s trail…

China’s Tianwen-1 orbiter caught a rare glimpse of 3I/ATLAS as it swept past Mars, revealing the hazy coma and tail of a comet born beyond our solar system. The interstellar object known as 3I/ATLAS just flew past Mars, and China’s Tianwen-1 mission managed to snap some pics with its high-resolution camera. According to the China [...]

Looking for a sky event this week? Check out our full Sky This Week column.  July 17: The Moon skims south of Venus Comet 10P/Tempel (also called Tempel 2) is closing in on the Sun for an early August perihelion. It’s now undergoing some spectacular visual changes as Earth passes through the plane of the comet’s orbit. As Continue reading "The Sky Today on Saturday, July 18: Comet Tempel’s knife-…

In July 1992, Comet Shoemaker-Levy 9 made its closest approach to Jupiter, skimming 25,000 miles (40,000 km) above Jupiter’s cloud tops. That put Shoemaker-Levy 9 within the gas giant’s Roche limit; the planet’s tidal forces broke the comet into more than 20 pieces, giving it a “string of pearls” appearance and setting the stage for Continue reading "July 8, 1992: Comet Shoemaker-Levy 9 breaks up…

Observations of the fast-moving interstellar comet with the Very Large Telescope in Chile support similar observations made by the JWST.

Chris Schur, taken from Payson, Arizona In 1983, NASA’s pioneering Infrared Astronomical Satellite (IRAS) imaged the sky and found dust trails littered throughout the solar system. The cause turned out to be comets, which leave trails of dust that build up in their orbit. The dust trail of 10P/Tempel (also known as Comet Tempel 2) Continue reading "Comet Tempel 2’s dust trail" The post Comet Temp…

3I/ATLAS , also known as C/2025 N1 (ATLAS) and formerly designated as A11pl3Z , is an i interstellar comet. It was discovered by the Asteroid Terrestrial-impact Last Alert System (ATLAS) station at Río Hurtado , Chile on 1 July 2025. Note: it was mentioned (as... Read more

As interstellar comet 3I/ATLAS began moving away from the Sun in December 2025, astronomers took the opportunity to turn NASA’s powerful James Webb Space Telescope in its direction and capture detailed measurements of its chemical components. The comet was freshly warmed from its closest pass by the Sun, and its ancient ice had been converted […] The post NASA’s Webb Finds Clues to Ancient, Dista…

Looking for a sky event this week? Check out our full Sky This Week column.  June 12: The Moon meets Mars Turn your telescope toward southern Pisces this morning, where Saturn outshines any of the stars in this part of the sky. This is where Comet 220P/McNaught recently underwent an outburst, quickly brightening from 18th magnitude to Continue reading "The Sky Today on Saturday, June 13: Catch Co…

We witnessed a surprise outburst late last week, from a lesser known periodic comet. Posts flashed across message boards late last week, alerting comet watchers to a dramatic change in brightness for periodic comet 220P McNaught. Though it wasn’t on our list for bright comets to watch for in 2026, Comet 220P is now in range of binoculars or a small telescope, low to the east at dawn as it heads t…

The James Webb Space Telescope observed a large amount of methane around 3I/ATLAS, revealing just how different it is from comets from our solar system.

Interstellar comet 3I/ATLAS was almost called 3I/Rubin, after researchers found that the giant survey telescope coincidentally spotted this visitor from the stars over a week before it was officially discovered.

When the interstellar comet 3I/ATLAS passed between ESA’s Jupiter Icy Moons Explorer (Juice) spacecraft and NASA’s Europa Clipper spacecraft in November 2025, scientists seized an once-in-a-lifetime chance: one spacecraft caught the comet’s glowing dayside, the other its dusty night side, simultaneously. The post Europa Clipper and Juice Team Up to Observe Interstellar Comet 3I/ATLAS appeared fir…

Looking for a sky event this week? Check out our full Sky This Week column.  May 9: Look the croc in the eye Although still best for experienced observers with larger scopes, Comet 10P/Tempel (also called Tempel 2) is quickly brightening. Glowing at roughly magnitude 15, Tempel 2 is currently in Aquila the Eagle, rising late in Continue reading "The Sky Today on Sunday, May 10: Can you catch Come…