05-08-2026, 09:42 AM
"3I/ATLAS Just Gave Scientists a Rare Look Inside an Interstellar Comet"
This is from https://www.bez-kabli.pl/3i-atlas-just-g...llar-comet which is not a place I think I ever linked to but it's a very interesting read.
3I/ATLAS is the third interstellar object we know about that entered our Solar System. There have likely been millions of others before we had the technology to detect them. However, we now know three objects have visited us from other solar systems because their orbits mean they came from outside the solar system and originated elsewhere in our Galaxy. Unlike the previous two objects, 3I/ATLAS showed all the indications it was a true comet - and iceball that formed in cold but dense enough regions for objects to coalesce. It then passed near our sun, and the comet's outer layers heated and were ejected. Those gases were measured by several telescopes, including the Subaru Observatory on Mauna Kea.
The gases were different from those of other comets we had observed before. Something was different, and it turns out, with help from other observatories, 3I/ATLAS formed in a much colder region than typical for solar system comets.
"Luis E. Salazar Manzano from the University of Michigan, who headed up the ALMA research, described the chemistry as “really sensitive to temperature,” and noted it tends to indicate regions colder than 30 Kelvin—roughly minus 406 Fahrenheit. That’s much colder than where most known solar-system comets originated."
There's more research to be done, though:
"But there are some important caveats. According to the Nature Astronomy team, this deuterium result is based on just one observing window, and ALMA itself didn’t actually pick up normal water above its detection limit during that session. Instead, the water output was estimated using models anchored partly on methanol line data. So the precise ratios may shift as researchers line up results from other dates and telescopes."
This is from https://www.bez-kabli.pl/3i-atlas-just-g...llar-comet which is not a place I think I ever linked to but it's a very interesting read.
3I/ATLAS is the third interstellar object we know about that entered our Solar System. There have likely been millions of others before we had the technology to detect them. However, we now know three objects have visited us from other solar systems because their orbits mean they came from outside the solar system and originated elsewhere in our Galaxy. Unlike the previous two objects, 3I/ATLAS showed all the indications it was a true comet - and iceball that formed in cold but dense enough regions for objects to coalesce. It then passed near our sun, and the comet's outer layers heated and were ejected. Those gases were measured by several telescopes, including the Subaru Observatory on Mauna Kea.
The gases were different from those of other comets we had observed before. Something was different, and it turns out, with help from other observatories, 3I/ATLAS formed in a much colder region than typical for solar system comets.
"Luis E. Salazar Manzano from the University of Michigan, who headed up the ALMA research, described the chemistry as “really sensitive to temperature,” and noted it tends to indicate regions colder than 30 Kelvin—roughly minus 406 Fahrenheit. That’s much colder than where most known solar-system comets originated."
There's more research to be done, though:
"But there are some important caveats. According to the Nature Astronomy team, this deuterium result is based on just one observing window, and ALMA itself didn’t actually pick up normal water above its detection limit during that session. Instead, the water output was estimated using models anchored partly on methanol line data. So the precise ratios may shift as researchers line up results from other dates and telescopes."