Comets Archives

October 31, 2024October 31, 2024 by Brian Koberlein

Astronomers Predict the Orbits of Potentially Hazardous Comets From Meteor Showers

Comets have long been seen as omens and portents, and it’s easy to understand why. They first appear as faint smudges of light in the sky, sometimes fading soon after and sometimes becoming brighter than the planets, with a long, glowing tail. They have been observed throughout human history, but it wasn’t until the eighteenth century that astronomers began to predict the return of some comets. Even today, we can’t predict the return of most comets until after they swing through the inner solar system. If such a comet happens to be heading toward Earth, we wouldn’t know about it until too late. But that could change thanks to our observations of meteor showers.

October 9, 2024October 9, 2024 by Mark Thompson

Good News. Comet Encke Only Threw a Handful of Giant Space Rocks in our Direction

This image taken by NASA's Spitzer Space Telescope shows the comet Encke riding along its pebbly trail of debris. Every October, Earth passes through Encke's wake, resulting in the well-known Taurid meteor shower.

As comets travel along their orbit they dump material along the way. A stream of debris known as the Taurid swarm has been keeping astronomers attention. It’s thought the debris is the remains of comet Encke which has also been fuelling the Taurid meteor shower. The swarm is believed to be composed of mostly harmless, tiny objects but there has been concern that there may be some larger, kilometre size chunks. Thankfully, new observations reveal there are of the order of 9-14 of these 1km rocks.

September 5, 2024September 5, 2024 by Mark Thompson

Explaining Different Kinds of Meteor Showers. It’s the Way the Comet Crumbles

The Universe often puts on a good show for us down here on Earth but one of the best spectacles must be a meteor shower. We see them when particles, usually the remains of comets, fall through our atmosphere and cause the atmosphere to glow. We see them as a fast moving streak of light but a new paper has suggested that the meteor showers we see can explain the sizes of the particles that originally formed the comet from where they came.

July 16, 2024July 16, 2024 by Carolyn Collins Petersen

More Than Half of Near Earth Objects Could Be “Dark Comets”

An artist's concept of a dark comet floating in space. Courtesy Nicole Smith.

Next time you’re visiting the seaside or a large lake, or even sipping a frosty glass of water, think about where it all originated. There are many pathways that water could have taken to the infant Earth: via comets, “wet asteroids”, and outgassing from early volcanism. Aster Taylor, a University of Michigan graduate student has another idea: dark comets. They’re something of a cross between asteroids and comets and could have played a role in water delivery to our planet.

May 26, 2024May 26, 2024 by Carolyn Collins Petersen

A Weather Satellite Watched a Space Rock Burn Up Above Spain and Portugal

A map of the track of the vaporizing space rock that lit up skies over Portugal and Spain on May 18, 2024. The track was created from position measurements of the fireball flashes as seen by ESA's MeteoSat weather satellite. Courtesy ESA.

It’s been a momentous May for skywatchers around the world. First the big auroral event of May 10-11, next a flaming space rock entering over Spain and Portugal. The inbound object was captured by ground-based cameras and the MeteoSat Third Generation Imager in geostationary orbit.

March 28, 2024March 28, 2024 by Nancy Atkinson

Someone Just Found SOHO's 5,000th Comet

The 5,000th comet discovered with the Solar and Heliospheric Observatory (SOHO) spacecraft is noted by a small white box in the upper left portion of this image. A zoomed-in inset shows the comet as a faint dot between the white vertical lines. The image was taken on March 25, 2024, by SOHO’s Large Angle and Spectrometric Coronagraph (LASCO), which uses a disk to block the bright Sun and reveal faint features around it. Credit: NASA/ESA/SOHO

The Solar and Heliospheric Observatory (SOHO) was designed to examine the Sun, but as a side benefit, it has been the most successful comet hunter ever built. Since early in the mission, citizen scientists have been scanning through the telescope’s data, searching for icy objects passing close to the Sun. An astronomy student in Czechia has identified 200 comets in SOHO data since he started in 2009 at the age of 13. He recently spotted the observatory’s 5,000th comet.

February 27, 2024February 27, 2024 by Laurence Tognetti

Comets: Why study them? What can they teach us about finding life beyond Earth?

Image of Comet 67P/Churyumov-Gerasimenko taken by the European Space Agency’s (ESA) Rosetta spacecraft on Jan. 31, 2015. There's a jet of material streaming from the comet as it's warmed by the Sun. (Credit: ESA/Rosetta/NAVCAM – CC BY-SA IGO 3.0)

Universe Today has explored the importance of studying impact craters, planetary surfaces, exoplanets, astrobiology, and solar physics, and what this myriad of scientific disciplines can teach scientists and the public regarding the search for life beyond Earth. Here, we will explore some of the most awe-inspiring spectacles within our solar system known as comets, including why researchers study comets, the benefits and challenges, what comets can teach us about finding life beyond Earth, and how upcoming students can pursue studying comets. So, why is it so important to study comets?

February 23, 2024February 23, 2024 by Carolyn Collins Petersen

A Star Passed Through the Oort Cloud Less Than 500,000 Years Ago. It Wasn’t the Only One.

Stars travel throughout the Galaxy. It's inevitable that some will pass near the Sun and perhaps even through our Oort Cloud, with interesting consequences. Credit: NASA/ESA/STScI.

As stars in the Milky Way move through space, some of them have an unexpected effect on the Solar System. Over time, one comes closer to the Sun during its orbit in the galaxy. Some of them actually get within a light-year of our star and pass through the Oort Cloud. Such close flybys can affect the orbits of the outer planets and send cometary nuclei on a long inward rush to the Sun.

November 9, 2023November 9, 2023 by Nancy Atkinson

Some of the Moon's Craters are From Interstellar Impacts. Can We Tell Which?

Far Side of Moon Imaged by MoonKAM. This image of the lunar surface was taken by the MoonKAM system onboard NASA’s Ebb spacecraft on March 15, 2012. Credit: NASA/Caltech-JPL/MIT/SRS

By discovering two interstellar objects (ISOs), we know that asteroids and comets from other star systems pass through the Solar System from time to time. By inference, some of these must have crashed into the Moon, creating impact craters. If we could study the impact sites, we might be able to learn about the star systems that they came from.

A new paper suggests there could be a way to determine which lunar craters came from interstellar object impacts. The authors say that young, small craters with high-melt volume near the Moon’s equator are likely the best candidates for ISO-generated craters on the lunar surface.

May 17, 2023May 17, 2023 by Evan Gough

JWST Finds a Comet Still Holding Onto Water in the Main Asteroid Belt

This artist's illustration shows the rocky body of a comet with a detailed, cratered surface. Glowing rays emanate from the rocky surface like sunlight through clouds, representing water ice being vapourised by the heat of the Sun. Image Credit: NASA, ESA

Comets are instantly recognizable by their tails of gas and dust. Most comets originate in the far, frozen reaches of our Solar System, and only visit the inner Solar System occasionally. But some are in the Main Asteroid Belt, mixed in with the debris left over after the Solar System formed.

Astronomers just found water vapour coming from one of them.

“With Webb’s observations of Comet Read, we can now demonstrate that water ice from the early Solar System can be preserved in the asteroid belt.”
Michael Kelley, University of Maryland