Comets Archives

April 16, 2020April 16, 2020 by Evan Gough

Astronomers Finally Think They Understand Where Interstellar Object Oumuamua Came From and How it Formed

Artist’s impression of the first interstellar asteroid/comet, "Oumuamua". This unique object was discovered on 19 October 2017 by the Pan-STARRS 1 telescope in Hawaii. Credit: ESO/M. Kornmesser

‘Oumuamua caused quite a stir when it visited our Solar System in 2017. It didn’t stay long, however, and when it was spotted with the Pan-STARRS telescope in Hawaii on October 19th, it was already leaving. But its appearance in our part of the Universe spawned a lot of conjecture on its nature and its origins.

April 13, 2020April 13, 2020 by Evan Gough

When Comets Break Up, the Fragments Can Be Devastating If They Hit the Earth

Artist's conception of asteroids or comets bearing water to a proto-Earth. Credit: Harvard-Smithsonian Center for Astrophysics

Comet breakups are a timely topic right now. The interstellar comet 2I/Borisov just broke into at least two pieces. And though that comet is speeding out of the Solar System, never to be seen again, most of them don’t leave the Solar System. Most of them orbit the Sun, and return to the inner Solar System again and again.

A new paper examines the potential hazard to Earth from comets that break into pieces. The author makes the case that comet breakups could have had a hand in shaping the ebb and flow of life on Earth. It could happen again.

April 9, 2020April 9, 2020 by Evan Gough

Interstellar Comet 2I/Borisov Appears to Have Broken in Half

In 2019, amateur astronomer Gennadiy Borisov discovered a comet, which now bears his name. There’s a long history of amateur astronomers discovering comets, as they approach our inner Solar System on their elongated orbits. But this one was different: it was moving much too fast to be gravitationally bound to the Sun.

It was an interstellar comet. And now, it looks like it has split into two chunks.

January 23, 2020January 23, 2020 by Evan Gough

Rosetta Saw the Building Blocks of Life on Comet 67P

Comet 67P as seen by Rosetta on 7 July 2015. By ESA/Rosetta/NAVCAM, CC BY-SA IGO 3.0, CC BY-SA 3.0-igo, https://commons.wikimedia.org/w/index.php?curid=41733207

Why is there so little nitrogen in Comet 67P/Churyumov-Gerasimenko (67P)? That’s a question scientists asked themselves when they looked at the data from the ESA’s Rosetta spacecraft. In fact, it’s a question they ask themselves every time they measure the gases in a comet’s coma. When Rosetta visited the comet in 2014, it measured the gases and found that there was very little nitrogen.

In two new papers published in Nature Astronomy, researchers suggest that the nitrogen isn’t really missing at all, it’s just hidden in the building blocks of life.

October 19, 2019October 19, 2019 by Matt Williams

Comets and Interstellar Objects Could be Exporting Earth Life Out into the Milky Way

An artist’s overview of the mission concept for the Comet Interceptor spacecraft, which will fly from the vicinity of Earth to rendezvous with a long-period comet or interstellar object inbound from the outer solar system. Credit: ESA

For over a century, proponents of Panspermia have argued that life is distributed throughout our galaxy by comets, asteroids, space dust, and planetoids. But in recent years, scientists have argued that this type of distribution may go beyond star systems and be intergalactic in scale. Some have even proposed intriguing new mechanisms for how this distribution could take place.

For instance, it is generally argued that meteorite and asteroid impacts are responsible for kicking up the material that would transport microbes to other planets. However, in a recent study, two Harvard astronomers examine the challenges that this would present and suggest another means – Earth-grazing objects that collect microbes from our atmosphere and then get flung into deep-space.

October 17, 2019October 17, 2019 by Evan Gough

Here’s the Picture We’ve Been Waiting for. Hubble’s Photo of Interstellar Comet 2I/Borisov

A Hubble image of comet 2I/Borisov speeding through our Solar System. Image Credit: NASA, ESA, and D. Jewitt (UCLA)

Leave it up to the good ole Hubble Space Telescope. The workhorse telescope has given us a photo of the new interstellar comet 2I/Borisov. Take that, fancy new telescopes.

September 14, 2019September 14, 2019 by Matt Williams

Images are Starting to Come in of the New Interstellar Comet

On August 30th, amateur astronomer Gennady Borisov spotted a comet of extrasolar origin passing through our Solar System. This is the second time in as many years that an interstellar object has been observed (the last being ‘Oumuamua 2.0 in 2017). Thanks to the Gemini Observatory, we now have pictures of this comet, making it the first object of its kind to be successfully imaged in multiple colors!

August 15, 2019August 15, 2019 by Evan Gough

An Astrophotographer Noticed a Chunk of Ice Orbiting Comet 67P in Rosetta’s Photos

"Churymoon," comet 67P/Churymuov-Gerasimenko's tiny, icy companion. It was brought to light by Spanish astrophotographer Jacint Roger who was working with the archive of images from the ESA's Rosetta mission. Image Credit: ESA/Rosetta/MPS/OSIRIS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA/J. Roger (CC BY-SA 4.0)

The European Space Agency’s (ESA) Rosetta mission spent two years at the comet 67P/Churyumov-Gerasimenko. At the end of September 2016, its mission was ended when the spacecraft was sent on a collision course into the comet. During its time at comet 67P, it captured a vast amount of images.

The ESA made all those images freely available at their Rosetta website, and now an astro-photographer working with those images has found something interesting: a chunk of ice travelling through space with 67P.

June 29, 2019June 29, 2019 by Evan Gough

Meet the Comet Interceptor. It’ll Wait Patiently In Space for a Comet, Then Pounce On It

The ESA has announced a new mission to explore a comet. The Comet Interceptor mission will have a spacecraft wait in space until a pristine comet approaches the inner Solar System. Then it will make a bee line for it, and do some ground-breaking science.

April 17, 2019April 17, 2019 by Evan Gough

Astronomers Find a Chunk of a Comet Inside a Meteorite

A slice from the LaPaz 02342 meteorite which contains dust grains from an ancient comet. Image Credit: Carnegie Institution/Nittler et. al. 2019.

The early days of the Solar System are hard to piece together from our vantage point, billions of years after it happened. Now a team of scientists have found a tiny chunk of an ancient comet inside an ancient meteorite. They say it sheds light on the early days of the Solar System when planets were still forming.