All posts tagged: comets

We’ve caught a comet switching its spin direction for the first time

We’ve caught a comet switching its spin direction for the first time

Published by skeptic

An artist’s impression of comet 41P as it approached the sun and shot material off into space NASA, ESA, CSA, Ralf Crawford (STScI) A small comet seems to have switched the direction in which it is rotating – the first time astronomers have seen evidence of such behaviour. Changes like this may help us learn about the insides of comets, which could reveal information about the composition of the early solar system. Comet 41P/Tuttle-Giacobini-Kresák, or simply 41P, measures about 1 kilometre across and takes around 5.4 years to orbit the sun. We can only see it when it visits the inner solar system and its trajectory happens to take it relatively close to Earth. It was last seen in 2017. In March that year, it was rotating at a rate of about one full spin every 20 hours. When astronomers observed it just two months later, it had slowed down dramatically to one spin every 46 to 60 hours. Now, David Jewitt at the University of California, Los Angeles, has reanalysed observations from the Hubble …

Mysterious comet disintegration caught by telescope after lucky break

Mysterious comet disintegration caught by telescope after lucky break

Published by skeptic

Comet K1 captured by the Hubble Space Telescope NASA, ESA, Dennis Bodewits (AU) By a stroke of luck, we have seen a comet just days after it cracked into four pieces. This could provide a crucial window into the history of the solar system. John Noonan at Auburn University in Alabama and his colleagues had planned to observe a different comet with the Hubble Space Telescope, but limitations to the spacecraft’s ability to turn quickly made that impossible, so they found a new target: a comet called C/2025 K1 (ATLAS). When they pointed Hubble at K1, they saw not a single comet but four fragments. “We have seen comets break up before – we’ve seen them break up from the ground all the time – but this one wasn’t known to have broken up when we looked at it,” says Noonan. “The amount of sheer luck that came into acquiring these images cannot be overstated.” We have never taken such clear pictures of a comet that’s just broken up before, because it is hard to …

3I/ATLAS: Interstellar comet has water unlike any in our solar system

3I/ATLAS: Interstellar comet has water unlike any in our solar system

Published by skeptic

3I/ATLAS is pretty strange International Gemini Observatory/NOIRLab/NSF/AURA/B. Bolin The interstellar comet 3I/ATLAS contains water and carbon molecules at levels never before seen in our solar system. This suggests that it formed around an alien star radically different from and much older than the sun. Astronomers have been tracking 3I/ATLAS since it entered our solar system last year – and it is weird. It appears to be packed with far more carbon dioxide and water than almost any other comet we have seen, and early estimates put its age at 8 billion years – almost twice as old as the sun. Now, Martin Cordiner at NASA’s Goddard Space Flight Center in Maryland and his colleagues have found that its levels of deuterium – a form of hydrogen with an extra neutron – are at least 10 times higher than in any comet we have seen before. Deuterium naturally exists in small amounts in Earth’s oceans, but the levels in 3I/ATLAS are more than 40 times higher. “3I/ATLAS continues to astonish us with what it reveals about …

Interstellar Comet 3I/Atlas Has Another Surprise: It’s Full of Alcohol

Interstellar Comet 3I/Atlas Has Another Surprise: It’s Full of Alcohol

Published by skeptic

Comet 3I/Atlas is now heading out of the solar system and into interstellar space, but scientists are still analyzing the data it left behind as it passed through our cosmic neighborhood. A new study, still under review, reveals a surprising detail: The comet is laden with alcohol. Observations from the ALMA telescope in Chile’s Atacama Desert show that the coma of this celestial object is heavily enriched in methanol, a type of alcohol common in fuels and solvents. Although methanol is commonly found in comets in the solar system, 3I/Atlas contained up to four times the typical amount. According to the study, available at arXiv, 3I/Atlas is the second most methanol-rich comet ever measured, behind only the unusual C/2016 R2, discovered 10 years ago. Parallel investigations have also detected high abundances of other organic compounds, such as carbon dioxide, iron, and nitrogen, reinforcing the idea that this object has an out-of-the-ordinary composition. The combination of excess methanol, a carbon dioxide-dominated coma, and other atypical chemical ratios supports the hypothesis that 3I/Atlas formed in an environment …

JWST solves a longstanding cosmic mystery about comet crystals

JWST solves a longstanding cosmic mystery about comet crystals

Published by Jenni Sidey

Using NASA’s James Webb Space Telescope, astronomers from Seoul National University and other international institutions have been able to answer a question that has puzzled scientists for years about how rocky materials formed in planetary systems. By studying the young star EC 53, the astronomers present evidence that crystallized minerals form near a newly created star and move outward into cooler regions where comets and planets develop. The research team, led by Jeong-Eun Lee at Seoul National University, studied EC 53, a Sun-like protostar located deep in the Serpens Nebula about 1,300 light years from Earth, which is filled with stars still forming. The team’s results were published in Nature. Crystalline silicates are regularly found in comets that have formed in our Solar System. These materials require very high levels of heat, greater than 900 Kelvin, to form, which is a significant mystery since comets spend the bulk of their lives far away from the Sun and frozen solid. Scientists have long thought that crystallized materials formed near a newly formed star and travelled outward, …

Did an exploding comet end the age of the wooly mammoths? New evidence says yes

Did an exploding comet end the age of the wooly mammoths? New evidence says yes

Published by Jenni Sidey

Almost 13,000 years ago, North America underwent drastic changes at a rapid rate. Mammoths, mastodons, giant ground sloths, and many other large animals went extinct. Around the same time, the Clovis Culture, famous for its well-made fluted stone tools, also disappeared from North America. During this time, the Earth experienced an abrupt return to nearly ice-age conditions, known as the Younger Dryas, due to a prolonged cold spell. There has been substantial debate among scientists over the years as to whether the extinction of large animals and the disappearance of the Clovis culture were linked or simply a coincidence. A new study published in PLOS ONE adds to the growing body of research indicating that a comet-like object impacted Earth, triggering the massive changes seen in North America at this time. James Kennett, an Emeritus Professor of Earth Science at the University of California, Santa Barbara, along with an international team of geologists and archaeologists, conducted the study. Site map. Location of study sites in California, Arizona, and New Mexico. (CREDIT: PLOS One) The study …

Comet 3I/ATLAS from beyond solar system carries key molecule for life

Comet 3I/ATLAS from beyond solar system carries key molecule for life

Published by skeptic

Comet 3I/ATLAS is only the third known visitor to our solar system from elsewhere International Gemini Observatory/NOIRLab/NSF/AURA/Shadow the Scientist; J. Miller & M. Rodriguez (Intl Gemini Observatory/NSF NOIRLab), T.A. Rector (University of Alaska Anchorage/NSF NOIRLab), M. Zamani (NSF NOIRLab) The interstellar comet 3I/ATLAS is belching out carbon-rich chemical compounds at higher rates than almost any other comet in our solar system. One of these compounds is methanol, a key ingredient in prebiotic chemistry that hasn’t been seen in other interstellar objects. 3I/ATLAS, which is only the third visitor to our solar system from elsewhere in the galaxy, appears to be quite unlike any comet from our own galactic neighbourhood. As it travelled towards the sun, an envelope of water vapour and gas rapidly grew around it, which also contained much greater amounts of carbon dioxide than we see in typical solar system comets. The comet’s light also appeared to be much redder than is typical, indicating a possible unusual surface chemistry, and it began releasing its gases while relatively far away from the sun, an …