{"id":3045,"date":"2025-09-19T19:05:04","date_gmt":"2025-09-19T19:05:04","guid":{"rendered":"http:\/\/terrarara.com.br\/en\/?page_id=3045"},"modified":"2025-09-19T19:05:04","modified_gmt":"2025-09-19T19:05:04","slug":"cometa-interestelar-3iatlas-esta-ficando-mais-brilhante-do-que-o-esperado","status":"publish","type":"page","link":"https:\/\/terrarara.com.br\/en\/?page_id=3045","title":{"rendered":"Interstellar comet 3i\/atlas is brightening more than expected"},"content":{"rendered":"
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Here”s one of the newest images of interstellar object Comet 3I\/ATLAS. The Gemini Multi-Object Spectrograph (GMOS) on the Gemini South telescope at Cerro Pach\u00c3\u00b3n in Chile captured this image, which NOIRLab released on September 4, 2025. The colors of the background stars are due to 4 filters. The comet was fixed in the center of the telescope”s field of view, while the positions of the background stars changed, showing streaks. Image via International Gemini Observatory\/ NOIRLab\/ NSF\/ AURA\/ Shadow the Scientist. Image Processing: J. Miller & M. Rodriguez (International Gemini Observatory\/NSF NOIRLab), T.A. Rector (University of Alaska Anchorage\/NSF NOIRLab), M. Zamani (NSF NOIRLab).<\/figcaption><\/figure><\/div>
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\r\n\t#3I\/Atlas<\/a>\u00c2\u00a0<\/p>

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\r\n\tComet 3I\/ATLAS, a visitor from another star system, is brightening faster than scientists predicted<\/strong><\/p>

Until recently, it followed the expected pattern of increasing in brightness as it approached the Sun.<\/p>

\r\nBut in mid-September 2025, observations showed that it was becoming brighter than normal for a comet approaching the Sun.<\/p>

\r\nComets are unpredictable, so we don’t know if this increase means it will become even more visible or if it’s just a temporary flare.<\/p>

\r\nOnly time will tell.\r\n<\/p>

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As of mid-September, the data at the Comet Observation database (COBS), maintained by Crni Vrh Observatory, shows that interstellar comet 3I\/ATLAS is outperforming expectations. The comet is brightening faster than expected. Is it just an outburst, and it will return to a slightly dimmer state? Or will it be brighter than scientists 1st thought? That remains to be seen. Image via COBS (CC BY 4.0).<\/figcaption><\/figure><\/div>
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Why is the comet brightening? <\/b>\r\n<\/p>

\r\nWhen a comet approaches the Sun, the water ice on its surface turns directly to gas in a process called sublimation.<\/p>

\r\nThis process releases dust particles that were trapped in the comet’s nucleus.<\/p>

\r\nThis gas and dust form the bright, diffuse coma we see, along with the comet’s tail.\r\n<\/p>

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This diagram shows the thin disk of the Milky Way in teal and the thick disk in yellow. A new paper said Comet 3I\/ATLAS likely came from the Milky Way”s thin disk. Image via Gaba P\/ Wikipedia (CC BY-SA 3.0).<\/figcaption><\/figure><\/div>
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Mars Flyby <\/b>\r\n<\/p>

\r\nIf the comet maintains this brightness, it could put on a beautiful spectacle as it passes Mars on October 3, 2025, at 4:00 AM (UTC, or 1:00 AM Bras\u00c3\u00adlia time).<\/p>

\r\nIt will be closest to Mars at this time, and some probes that normally observe the red planet, such as the Mars Reconnaissance Orbiter, the European Space Agency’s (ESA) Trace Gas Orbiter, and Mars Express, will turn their cameras toward the comet.<\/p>

\r\nThis could provide us with incredible images of this interstellar visitor.\r\n<\/p>

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The Hubble Space Telescope captured this image of interstellar object 3I\/ATLAS on July 21, 2025. It was the sharpest image yet of the object, acquired when the object was 226 million miles (364 million km) from Earth. This object is now generally believed to be a comet by most astronomers. In this image, a comet-like, teardrop-shaped cocoon of dust can be seen coming off its solid, presumably icy nucleus. Image via NASA\/ ESA\/ D. Jewitt (UCLA); Image Processing: J. DePasquale (STScI).<\/figcaption><\/figure><\/div>
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Where did 3I\/ATLAS come from? <\/b>\r\n<\/p>

\r\nA team led by Xabier P\u00c3\u00a9rez-Couto of the University of A Coru\u00c3\u00b1a in Spain has tracked the path of comet 3I\/ATLAS for 10 million years.<\/p>

\r\nThis is only the third known interstellar object to enter our solar system, meaning it wasn’t born here, but came from another star system.<\/p>

\r\nScientists wanted to determine which star it came from or if any star altered its path as it traveled to us.\r\n<\/p>

\r\nUsing data from the Gaia space observatory, which has mapped billions of stars in the Milky Way for 12 years, researchers analyzed the comet’s path.<\/p>

\r\nThey calculated that it traveled more than 100 million astronomical units (AU, the distance between Earth and the Sun) to get here.<\/p>

\r\nThey identified 93 possible “encounters” with stars, 62 of which were considered significant, but none of them were close enough to alter the comet’s path.<\/p>

\r\nThus, they were unable to identify 3I\/ATLAS’s star of origin.\r\n<\/p>

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Hubble Space Telescope images of interstellar comet 3I\/ATLAS are out! These were taken 5 hours ago. Plenty of cosmic rays peppering the images, but the comet’s coma looks very nice and puffy. Best of luck to the researchers trying to write up papers for this… archive.stsci.edu\/proposal_sea… ?

[image or embed]<\/a><\/p>? astrafoxen (@astrafoxen.bsky.social<\/a>) 21 de julho de 2025 \u00c3\u00a0s 18:28<\/a><\/blockquote>