On 12 November 2014, after a ten year journey through the Solar System and over 500 million kilometres from home, Rosetta’s lander Philae made space exploration history by touching down on a comet for the first time. On the occasion of the tenth anniversary of this extraordinary feat, we celebrate Philae’s impressive achievements at Comet 67P/Churyumov-Gerasimenko.
Scientists revealed unexpected outgassing from this object galloping across the outer solar system.
Similar to the Ancient Greek mythological creature of the same name, centaurs in astronomy are in an in-between dynamical phase: leaving their distant and stable orbits beyond Neptune and migrating to the inner solar system, while also entering an active cometary phase. Being stored for billions of years in the freezing confines of the outer solar system, they preserve key insights about the birth of our solar system, which are uniquely revealed as they slowly start to unfreeze in this transient stage.
Using NASA’s James Webb Space Telescope, a team of astronomers observed Centaur 29P/Schwassmann-Wachmann 1, one of the most active and intriguing objects in the outer solar system. The high degree of detail captured by the telescope led to the discovery of new, previously unknown jets of gas, which is helping inform theories about how centaurs and planets are formed.
Comet Tsuchinshan-Atlas is a bright comet that’s about to fly around the Sun and pass near Earth. It’s possible to see the comet in the pre-dawn sky right now, and in a couple of weeks, when the comet makes its closest approach to Earth, it may offer an even more impressive sight. Only time will tell for sure.
On March 25, 2024, a citizen scientist in the Czech Republic spotted a comet in an image from the Solar and Heliospheric Observatory (SOHO) spacecraft, which has now been confirmed to be the 5,000th comet discovered using SOHO data. SOHO has achieved this milestone over 28 years in space, even though it was never designed to be a comet hunter.
The new comet to look for with the naked eye.
A new comet is visible in the predawn skies as it passes close to Earth on its journey around the Sun. Comet Nishimura is green in color with a long, white tail. It will make its closest pass by Earth on Sept. 12, 2023, and then will carry on toward the Sun.
We have known for a while that asteroid 3200 Phaethon acts like a comet. It brightens and forms a tail when it's near the Sun, and it is the source of the annual Geminid meteor shower, even though comets are responsible for most meteor showers. Scientists had blamed Phaethon's comet-like behavior on dust escaping from the asteroid as it's scorched by the Sun. However, a new study using two NASA solar observatories reveals that Phaethon's tail is not dusty at all but is actually made of sodium gas.
CBET 5134 & MPEC 2022-L97, issued on 2022, June 13, announce that an apparently asteroidal object discovered on June 4 with the 0.68-m Schmidt reflector of the Catalina Sky Survey has been found to show cometary appearance by CCD astrometrists elsewhere after the Minor Planet Center posted it to the PCCP webpage on the basis of a comet-like orbit. The new comet has been designated C/2022 L1 (Catalina).
Astronomers using a fleet of world leading telescopes on the ground and in space have captured images of a periodic rocky near-Sun comet breaking apart. This is the first time such a comet has been caught in the act of disintegrating and could help explain the scarcity of such periodic near-Sun comets.
ESA’s Comet Interceptor mission to visit a pristine comet or other interstellar object just starting its journey into the inner Solar System has been ‘adopted’ this week; the study phase is complete and, following selection of the spacecraft prime contractor, work will soon begin to build the mission.
CBET 5113 & MPEC 2022-G83, issued on 2022, April 06, announce the discovery of a comet (magnitude ~17) in infrared exposures obtained during Mar. 30-Apr. 1 UT with the Near-Earth Object Wide-field Infrared Survey Explorer (or NEOWISE; formerly the WISE earth-orbiting satellite). The new comet has been designated C/2022 F2 (NEOWISE).
CBET 5112 & MPEC 2022-G82, issued on 2022, April 06, announce the discovery of a comet (magnitude ~18.5) on CCD images taken on Mar. 30.3 UT with a 0.5-m f/2 Wright-Schmidt reflector at Rio Hurtado, Chile, in the course of the "Asteroid Terrestrial-Impact Last Alert System" (ATLAS) search program. The new comet has been designated C/2022 F1 (ATLAS).