This illustration of Comet 238P/Read reveals the main belt comet sublimating– its water ice vaporizing as its orbit approaches the Sun. This is considerable, as the sublimation is what distinguishes comets from asteroids, creating their distinctive tail and hazy halo, or coma. It is particularly crucial for Comet Read, as it is one of 16 recognized main belt comets discovered in the asteroid belt, instead of the colder Kuiper Belt or Oort Cloud, more remote from the Sun. Comet Read was among three comets used to specify the class of main belt comets in 2006. Credit: NASA, ESA
The James Webb Space Telescopes latest discovery is a tale of 2 detections.
Planetary system researchers took NASAs James Webb Space Telescope on a treasure hunt in the asteroid belt, and what they didnt find turned out to be as substantial as what they did. If a spectrum of possible chemical compounds serves as a map of what to search for, X marked the area of water vapor on Comet Read– a long-sought hint in the bigger mystery of how Earths liquid water, and consequently life, first came to be. Carbon dioxide was missing out on from the map, though it is present in all other comets. So in addition to continuing to pursue the history of ancient water in the planetary system, scientists have an unanticipated brand-new mission on their hands, and will be hunting for answers in our cosmic yard.
It shows the hazy halo, called the coma, and tail that are particular of comets, as opposed to asteroids. The dusty coma and tail result from the vaporization of ices as the Sun warms the primary body of the comet.
NASAs Webb Finds Water, and a New Mystery, in Rare Main Belt Comet.
NASAs James Webb Space Telescope has made it possible for another long-sought clinical advancement, this time for solar system researchers studying the origins of Earths abundant water. Using Webbs NIRSpec (Near-Infrared Spectrograph) instrument, astronomers have verified gas– specifically water vapor– around a comet in the main asteroid belt for the very first time, showing that water ice from the primordial solar system can be protected in that region. However, the successful detection of water features a brand-new puzzle: unlike other comets, Comet 238P/Read had no detectable carbon dioxide.
” Our water-soaked world, teeming with life and distinct in deep space as far as we understand, is something of a secret– were uncertain how all this water got here,” stated Stefanie Milam, Webb deputy task researcher for planetary science and a co-author on the research study reporting the finding. “Understanding the history of water circulation in the planetary system will help us to understand other planetary systems, and if they might be on their way to hosting an Earth-like world,” she added.
It is specifically essential for Comet Read, as it is one of 16 recognized main belt comets discovered in the asteroid belt, as opposed to the colder Kuiper Belt or Oort Cloud, more distant from the Sun. Comet Read was one of 3 comets utilized to define the class of primary belt comets in 2006. Discovering this in Comet Read was a significant achievement for Webb, as it is in a different class of comets than Jupiter-family comets like Hartley 2, and this marks the very first time that a gas has actually been validated in such a primary belt comet. Comet Read is a main belt comet– an object that lives in the main asteroid belt however which periodically displays a halo, or coma, and tail like a comet. Main belt comets themselves are a relatively brand-new classification, and Comet Read was one of the original three comets used to establish the category.
This graphic discussion of spectral information highlights a key resemblance and distinction in between observations of Comet 238P/Read by the NIRSpec (Near-Infrared Spectrograph) instrument on NASAs James Webb Space Telescope in 2022 and observations of Comet 103P/Hartley 2 by NASAs Deep Impact mission in 2010. Discovering this in Comet Read was a substantial accomplishment for Webb, as it is in a different class of comets than Jupiter-family comets like Hartley 2, and this marks the first time that a gas has actually been verified in such a primary belt comet.
Comet Read is a primary belt comet– an object that resides in the main asteroid belt but which occasionally displays a halo, or coma, and tail like a comet. Main belt comets themselves are a fairly brand-new classification, and Comet Read was one of the initial three comets used to establish the classification. Before that, comets were understood to reside in the Kuiper Belt and Oort Cloud, beyond the orbit of Neptune, where their ices might be protected further from the Sun. Frozen material that vaporizes as they approach the Sun is what offers comets their distinct coma and streaming tail, separating them from asteroids. Researchers have long speculated that water ice could be protected in the warmer asteroid belt, inside the orbit of Jupiter, but definitive proof was elusive– till Webb.
” In the past, weve seen things in the main belt with all the qualities of comets, however only with this exact spectral information from Webb can we say yes, its absolutely water ice that is producing that impact,” described astronomer Michael Kelley of the University of Maryland, lead author of the study.
” With Webbs observations of Comet Read, we can now demonstrate that water ice from the early planetary system can be protected in the asteroid belt,” Kelley stated.
Image of Comet 238P/Read caught by the Webb Telescopes NIRCam (Near-Infrared Camera), with compass arrows, scale bar, and color secret for reference.The north and east compass arrows show the orientation of the image on the sky. The color key reveals the filter utilized when collecting the light.Credit: NASA, ESA, CSA, Mike Kelley, Henry Hsieh (PSI), Alyssa Pagan (STScI).
Generally, carbon dioxide makes up about 10 percent of the unpredictable material in a comet that can be quickly vaporized by the Suns heat. One possibility is that Comet Read had carbon dioxide when it formed but has lost that since of warm temperature levels.
” Being in the asteroid belt for a very long time could do it– carbon dioxide vaporizes more quickly than water ice, and might percolate out over billions of years,” Kelley said. He said, Comet Read may have formed in an especially warm pocket of the solar system, where no carbon dioxide was available.
The next action is taking the research beyond Comet Read to see how other main belt comets compare, says astronomer Heidi Hammel of the Association of Universities for Research in Astronomy (AURA), lead for Webbs Guaranteed Time Observations for solar system things and co-author of the research study. Do other main belt comets also lack carbon dioxide?
Co-author Milam imagines the possibilities of bringing the research even closer to home. “Now that Webb has actually verified there is water preserved as close as the asteroid belt, it would be interesting to act on this discovery with a sample collection objective, and discover what else the main belt comets can inform us.”.
The research study is released in the journal Nature.
Referral: “Spectroscopic recognition of water emission from a main-belt comet” by Michael S. P. Kelley, Henry H. Hsieh, Dennis Bodewits, Mohammad Saki, Geronimo L. Villanueva, Stefanie N. Milam and Heidi B. Hammel, 15 May 2023, Nature.DOI: 10.1038/ s41586-023-06152-y.
