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https://www.eurekalert.org/news-releases/1132425
EXCERPTS: Northwestern University-led astronomers have discovered salty skies surrounding the universe’s famous “Pink Planet.”
For more than a decade, the ancient, rosy hazed world kept astronomers guessing. One of the coldest known planetary-mass companions ever directly imaged, the elusive object is too faint for astronomers to dissect its light from Earth. But new observations from the James Webb Space Telescope (JWST) reveal an atmosphere filled with exotic chemistry — and salty clouds unlike anything seen before.
The observations provide some of the first direct evidence for salt clouds in a cold object’s atmosphere, a phenomenon scientists theorized more than 15 years ago. The discovery also marks an important step toward studying increasingly cold objects, which are too dim to examine with ground-based telescopes.
The study is published in the Astronomical Journal.
“The Pink Planet is the coldest companion ever discovered using ground-based instruments,” said Northwestern’s Aneesh Baburaj, who led the study. “Many teams all around the world performed follow-up observations to study its light, but it was too faint for ground-based instruments. That made it a perfect target for JWST. When we finally obtained its spectrum, it immediately looked interesting. But once we started digging deeper into the data, we realized it was not like anything we have analyzed before.”
[...] “We ran simulations with clouds, and the results aligned with what we know about cold planets,” Baburaj said. “We tried three different types of clouds, and salt clouds fit best. When we accounted for salt clouds, it subdued the signature of molecules hidden deeper in the companion’s atmosphere. Then, the results became physically possible.”
The spectrum also suggested that GJ504b is unusually rich in heavy elements, or metals. However, the mystery of the object’s formation persists, with current data suggesting it could have formed either like a planet or a small star.
Baburaj says the techniques used in the study could help unravel other mysteries surrounding cold, faint planets. Jupiter, for example, hosts clouds made of ammonia ice. While those cloud types remain beyond the reach of current observations, the detection of GJ504b’s salt clouds suggests astronomers are getting closer... (MORE - details)
EXCERPTS: Northwestern University-led astronomers have discovered salty skies surrounding the universe’s famous “Pink Planet.”
For more than a decade, the ancient, rosy hazed world kept astronomers guessing. One of the coldest known planetary-mass companions ever directly imaged, the elusive object is too faint for astronomers to dissect its light from Earth. But new observations from the James Webb Space Telescope (JWST) reveal an atmosphere filled with exotic chemistry — and salty clouds unlike anything seen before.
The observations provide some of the first direct evidence for salt clouds in a cold object’s atmosphere, a phenomenon scientists theorized more than 15 years ago. The discovery also marks an important step toward studying increasingly cold objects, which are too dim to examine with ground-based telescopes.
The study is published in the Astronomical Journal.
“The Pink Planet is the coldest companion ever discovered using ground-based instruments,” said Northwestern’s Aneesh Baburaj, who led the study. “Many teams all around the world performed follow-up observations to study its light, but it was too faint for ground-based instruments. That made it a perfect target for JWST. When we finally obtained its spectrum, it immediately looked interesting. But once we started digging deeper into the data, we realized it was not like anything we have analyzed before.”
[...] “We ran simulations with clouds, and the results aligned with what we know about cold planets,” Baburaj said. “We tried three different types of clouds, and salt clouds fit best. When we accounted for salt clouds, it subdued the signature of molecules hidden deeper in the companion’s atmosphere. Then, the results became physically possible.”
The spectrum also suggested that GJ504b is unusually rich in heavy elements, or metals. However, the mystery of the object’s formation persists, with current data suggesting it could have formed either like a planet or a small star.
Baburaj says the techniques used in the study could help unravel other mysteries surrounding cold, faint planets. Jupiter, for example, hosts clouds made of ammonia ice. While those cloud types remain beyond the reach of current observations, the detection of GJ504b’s salt clouds suggests astronomers are getting closer... (MORE - details)