Recently in the Comets Category

This week's images of comet 67P/Churyumov-Gerasimenko reveal an extraordinarily irregular shape. We had hints of that in last week's images and in the unscheduled previews that were seen a few days ago, and in that short time it has become clear that this is no ordinary comet.

This short animation explains the relative sizes of the Rosetta spacecraft and comet 67P/Churyumov--Gerasimenko.

ESA's Rosetta spacecraft has found that comet 67P/Churyumov-Gerasimenko is releasing the equivalent of two small glasses of water into space every second, even at a cold 583 million kilometers from the Sun.

An image snapped earlier this month by ESA's Rosetta spacecraft shows its target comet has quietened, demonstrating the unpredictable nature of these enigmatic objects.

Three NASA science instruments aboard the European Space Agency's (ESA) Rosetta spacecraft, which is set to become the first to orbit a comet and land a probe on its nucleus, are beginning observations and sending science data back to Earth.

A comet discovered in 2004 will make a close approach this Friday resulting in what could be a spectacular meteor shower and possibly, though not likely, a meteor storm.

Rosetta is about to put on the brakes to ensure that it is on target for comet 67P/Churyumov-Gerasimenko.

Rosetta: When Can We See The Comet?

Visualisation of how comet 67P/Churyumov-Gerasimenko will appear in Rosetta's OSIRIS narrow angle camera between May and August 2014. During this time, the 4 kilometre-wide comet will 'grow' in Rosetta's field of view from appearing to have a diameter of less than 1 camera pixel to well over 2000 pixels -- equivalent to a resolution of around 2 metres per pixel -- allowing the large surface features to be resolved.

ESA's Rosetta spacecraft has caught a first glimpse of its destination comet since waking up from deep-space hibernation on 20 January.

NASA released Thursday an image of a comet that, on Oct. 19, will pass within 84,000 miles of Mars -- less than half the distance between Earth and our moon.

Rosetta's Comet Wakes Up

It's back! After comet 67P/Churyumov-Gerasimenko had disappeared behind the Sun and out of the Earth's view last year in October, the target comet of ESA's Rosetta mission can now be seen again.

The exploits of comet-hunting spacecraft Rosetta are generating intense interest as it speeds towards a dramatic climax this autumn.

It was a fairy-tale ending to a tense chapter in the story of the Rosetta space mission this evening as ESA heard from its distant spacecraft for the first time in 31 months.

Rosetta: To Chase a Comet

Comets are among the most beautiful and least understood nomads of the night sky. To date, half a dozen of these most heavenly of heavenly bodies have been visited by spacecraft in an attempt to unlock their secrets

Rosetta Spacecraft -- The Story so Far

This short movie tells the story of Rosetta's journey through the Solar System so far, through the voices of some of the many people involved in this exciting mission.

Rosetta's Orbit Around the Comet

After a ten year journey through space, ESA's Rosetta spacecraft will reach comet 67P/Churyumov-Gerasimenko in August 2014.

There are hundreds of comets flying around the Solar System, each of them a potential target for ESA's comet-chasing Rosetta mission.

The Life of Comet ISON

After several days of continued observations, scientists continue to work to determine and to understand the fate of Comet ISON.

The unusual shape of the comet's tail permits conclusions about yesterday's encounter with the sun November 29, 2013

Comet ISON May or May Not Still Exist

Comet ISON went around the sun on Nov. 28, 2013. Several solar observatories watched the comet throughout this closest approach to the sun, known as perihelion.

Comet ISON approaches the Sun

SOHO image showing comet ISON approaching the Sun. ISON makes its closest approach on 28 November, when it will pass at a distance of 1.2 million kilometres above the Sun's visible surface. SOHO's instruments are expected to have a view of the comet as it passes through their fields-of-view.

Comet ISON Streams Toward the Sun

In the early hours of Nov. 27, 2013, Comet ISON entered the field of view of the European Space Agency/NASA Solar and Heliospheric Observatory.

During an intensive commissioning run, Hyper Suprime-Cam (HSC), mounted at prime focus on the Subaru Telescope, has successfully imaged Comet ISON (C/2012 S1) as it journeys toward the Sun.

Watching ISON's Journey Around the Sun

It began in the Oort cloud, almost a light year away. It has traveled for over a million years. It has almost reached the star that has pulled it steadily forward for so long.

One or more fragments may have detached from comet ISON in the past days, as two wing-shaped features in the comet's atmosphere suggest.

Astronomers viewing our solar system's asteroid belt with NASA's Hubble Space Telescope have seen for the first time an asteroid with six comet-like tails of dust radiating from it like spokes on a wheel.

A new image of the Sunward plunging Comet ISON suggests that the comet is intact despite some predictions that the fragile icy nucleus might disintegrate as the Sun warms it. The comet will pass closest to the Sun on November 28.

ESA's comet-chasing mission Rosetta will wake up in 100 days' time from deep-space hibernation to reach the destination it has been cruising towards for a decade.

Comet ISON Details Beginning to Emerge

Scientists are unraveling more information on Comet C/2012 S1 (ISON) as it continues on its journey toward the Sun. ISON will skim 730,000 miles above the Sun's surface on Nov. 28 and has the potential to be readily visible from Earth starting in early December.

The first ever evidence of a comet entering Earth's atmosphere and exploding, raining down a shock wave of fire which obliterated every life form in its path, has been discovered by a team of South African scientists and international collaborators.

First HiRISE Images of Comet ISON

On 29 September 2013, the Mars Reconnaissance Orbiter (MRO) maneuvered to point its High Resolution Imaging Science Experiment (HiRISE) camera at ISON, a new comet passing by Mars on its way into the inner Solar System.

Comet ISON is still more than two months away from its spectacular close encounter with the sun. Already, the brightening comet has become a good target for backyard telescopes in the pre-dawn sky.

Will Comet ISON Break Up?

Comet ISON is an interesting comet in many ways, but we know it won't hit us. There is speculation among astronomers however, that it could break up into pieces.

For 30 years, a large near-Earth asteroid wandered its lone, intrepid path, passing before the scrutinizing eyes of scientists while keeping something to itself: (3552) Don Quixote, whose journey stretches to the orbit of Jupiter, now appears to be a comet.

The true identity of centaurs, the small celestial bodies orbiting the sun between Jupiter and Neptune, is one of the enduring mysteries of astrophysics.

Approaching the sun, Comet ISON floats against a seemingly infinite backdrop of numerous galaxies and a handful of foreground stars.

Astronomers using NASA's Spitzer Space Telescope have observed what most likely are strong carbon dioxide emissions from Comet ISON ahead of its anticipated pass through the inner solar system later this year.

Planetary astronomers and Host Tony Darnell hosted a Google Hangout discussion of Comet ISON, its origins and destination, and why everyone's so excited about it.

What is a Sungrazing Comet?

Sungrazing comets are a special class of comets that come very close to the sun at their nearest approach, a point called perihelion. To be considered a sungrazer, a comet needs to get within about 850,000 miles from the sun at perihelion. Many come even closer, even to within a few thousand miles.

This July Fourth, the solar system is showing off some fireworks of its own. Superficially resembling a skyrocket, comet ISON is hurtling toward the sun presently at a whopping 48,000 mph.

ALMA Discovers Comet Factory

Astronomers using the new Atacama Large Millimeter/submillimeter Array (ALMA) have imaged a region around a young star where dust particles can grow by clumping together. This is the first time that such a dust trap has been clearly observed and modelled.

It solves a long-standing mystery about how dust particles in discs grow to larger sizes so that they can eventually form comets, planets and other rocky bodies. The results are published in the journal Science on 7 June 2013.

A new series of images from Gemini Observatory shows Comet C/2012 S1 (ISON) racing toward an uncomfortably close rendezvous with the Sun. In late November the comet could present a stunning sight in the twilight sky and remain easily visible, or even brilliant, into early December of this year.

Scientists eagerly await the arrival of a recently discovered, highly active comet that will skim 730,000 miles above the Sun's surface on Nov. 28 and has the potential to be readily visible from Earth.

From NASA ScienceCast: "A comet is heading for Mars, and there is a chance that it might hit the Red Planet in October 2014. An impact wouldn't necessarily mean the end of NASA's Mars program. But it would transform the program along with Mars itself."

The latest trajectory of comet 2013 A1 (Siding Spring) generated by the Near-Earth Object Program Office at NASA's Jet Propulsion Laboratory in Pasadena, Calif., indicates the comet will pass within 186,000 miles (300,000 kilometers) of Mars and there is a strong possibility that it might pass much closer.

Comets trailing wispy tails across the night sky are a beautiful byproduct of our solar system's formation, icy leftovers from 4.6 billion years ago when the planets coalesced from rocky rubble.

Every six seconds, for millions of years, comets have been colliding with one another near a star in the constellation Cetus called 49 CETI, which is visible to the naked eye.

Scientists Monitor Comet Breakup

The Hergenrother comet is currently traversing the inner-solar system. Amateur and professional astronomers alike have been following the icy-dirt ball over the past several weeks as it has been generating a series of impressive outbursts of cometary-dust material. Now comes word that the comet's nucleus has taken the next step in its relationship with Mother Nature.

A team at Southern Illinois University Edwardsville has developed a new website, IceHunters (, to challenge the public to discover Kuiper Belt objects in the outer solar system. It is hoped that among the myriad of new objects found by IceHunters there will be an object (or maybe even objects) with just the right orbit to carry it on to a rendezvous with NASA's New Horizons spacecraft.

Amateur astronomers, including Nick James of Chelmsford, Essex, England, have captured video of the interesting object. James generated his video of GP59 on the night of Monday, April 11. The video, captured with an 11-inch Schmidt-Cassegrain telescope, is a compilation of 137 individual frames, each requiring 30 seconds of exposure. At the time, the asteroid was approximately 3,356,000 kilometers (2,081,000 miles) distant. Since then, the space rock has become something of a darling of the amateur astronomy community, with many videos available. Here is one recent posting: