时间:2025-07-09 17:35:36 来源:网络整理编辑:熱點
The corona isn't the only thing optimistic eclipse chasers will try to see when the moon completely
The corona isn't the only thing optimistic eclipse chasers will try to see when the moon completely covers the sun over parts of North America next month.
Spectators will have a wee chance of seeing a comet with the naked eye or a standard pair of binoculars during the total solar eclipse on April 8.
Comet 12/P Pons-Brooks, which makes an appearance in the inner solar system every 71 years, will have its closest approach to the sun just two weeks after the eclipse on April 21. The timing of the visit means it could be visible in the temporary twilight that comes with a blocked sun. The key will be whether the comet — a space snowball — will undergo a sudden flare-up called an outburst a day or so before, said Tony Farnham, an astronomer with expertise in comet activity at the University of Maryland.
"Its forecasted brightness is right at the limit of most people's ability to see that brightness, and that's in a darksky," Farnham told Mashable. But "The thing about this comet is that it has a history of going into outbursts, a couple of which have actually been fairly large."
SEE ALSO:How the 2024 solar eclipse will be different from the lastTweet may have been deleted
During the eclipse, the moon will cast its shadow across the continent, starting on Mexico's western coast at 11:07 a.m. PT, according to NASA, arcing from Texas to Maine, entering Canada through Ontario, and exiting on the Atlantic Coast from Newfoundland at 5:16 p.m. NDT. Major U.S. cities in this corridor, known as the "path of totality," will include Dallas, Indianapolis, and Cleveland.
Totality is a rare opportunity for residents to see the sun's glowing corona, the outer layer of the sun's atmosphere, usually swamped out by the much brighter solar surface. The peak moment will last up to four minutes and 28 seconds for the tens of millions of people viewing it in the shadow's path.
Comets can be spectacular astronomical events in their own right. They are enormous balls of ice, dust, and rock that formed in the outer solar system, left over from the early days of planet formation about 4.6 billion years ago. Their ice starts to disintegrate as they get closer to the sun, converting instantly from a solid to a gas, skipping over the liquid phase. That process creates their signature tails, millions-of-miles-long debris trails of vaporizing material.
Hundreds of years ago, comets were considered bad omens. Today, scientists know these icy bodies as time capsules of the ancient solar system. Some astronomers believe comets brought water and organic compounds — a.k.a. the building blocks of life — to early Earth.
In the months leading up to April 8, eclipse cartographer Michael Zeiler has already mentally begun planning out his precious 4.5 minutes of totality.
"I'll make a quick look for that comet," he said. "But I won't spend more than 10 seconds or so doing that."
This large comet — which could have a nucleus up to 21 miles wide — has been compared to Star Wars'Millennium Falcon or a devil with horns for its unusual shape. Experts don't fully understand what's causing this distortion of its coma, the gas cloud around its nucleus. The last time Pons-Brooks, recently nicknamed the "devil comet," swung by was in 1954.
Recently, the comet was popping in on the galaxy Andromeda in the early evening sky. But during the eclipse, it should be near Jupiter.
To locate it, Farnham recommends looking to the left of the totally eclipsed sun. About a hand's length away should be Jupiter, which will look like a bright point of light, like a star. Using the planet as a reference, you may find the comet nearby while scanning around it with binoculars.
"If you look up in that vicinity and you see something fuzzy, that's the comet," he said.
"If you look up in that vicinity and you see something fuzzy, that's the comet."
Remember that it's safe to use regular binoculars to look at a solar eclipse when the sun is completely concealed, but never during a partial eclipse, even if only the rim is exposed. Direct sunlight can also damage the optical parts of a camera, binoculars, or telescope — including the filters on protective solar eclipse glasses, if a person wears them while looking through one of these devices.
Still, astronomers are tempering people's expectations for catching a glimpse of Pons-Brooks. Nalin Samarasinha, a senior scientist and comet expert at the Planetary Science Institute, said the peak magnitude of Halley's Comet was around the same in 1986 as is predicted for this one on April 8, and he was unable to see Halley with the unaided eye in a predawn sky, a similar lighting condition to a total eclipse.
"I really doubt it will be a naked eye object (at least not with my eyesight)," he wrote in an email.
But for people planning to take pictures during totality, Samarasinha said it's worth trying some long exposures with a wide-angle camera, as Pon-Brooks might make a faint photobomb, particularly if it undergoes an outburst.
Though scientists don't know the exact cause of outbursts, one possibility is that heat waves from the sun make their way into a crack or pocket in the comet's nucleus, causing volatile gasses to then vaporize and shoot out material in a burst of energy. Another possibility is that as the comet evolves, a cliff or escarpment may form on the nucleus, exposing fresh material that then becomes active.
The ever-changing dynamics are what drew Farnham to studying comets in the first place: They're full of surprises. He plans to travel to Central Texas for the eclipse, and he will take a glance over for Pons-Brooks.
"If you see something, great, but if you don't, the real story here is the eclipse," he said.
This story originally published on March 9, 2024 and has been updated.
TopicsNASA
Sound the alarms: Simone Biles finally met Zac Efron2025-07-09 16:57
金童獎40人名單 :佩德裏領銜 卡馬文加榜上有名2025-07-09 16:54
索帥下課危機!曼聯鎖3位接替者 孔蒂或因C羅作罷2025-07-09 16:47
國足近期將公布熱身對手 兩場訓練賽間隔5天模擬12強賽2025-07-09 16:40
Pokémon Go is so big that it has its own VR porn parody now2025-07-09 16:13
歐冠首輪最佳陣容出爐 :阿賈克斯大贏家 萊萬入選2025-07-09 16:07
名宿談C羅場下指揮隊友:以他的地位沒人會反駁他2025-07-09 15:33
巴薩官宣鋒線絕對主力手術成功 2021年或提前報銷2025-07-09 15:10
You will love/hate Cards Against Humanity's new fortune cookies2025-07-09 14:58
瓜帥裏程碑戰歐冠勝場超溫格 格10傳射比肩魯小胖2025-07-09 14:54
Pole vaulter claims his penis is not to blame2025-07-09 17:34
法國名宿:皇薩等豪門嫉妒巴黎 隻當他們是暴發戶2025-07-09 17:10
魯梅尼格 :巴薩失去梅西就像丟了魂 西甲自擺烏龍2025-07-09 17:08
詹俊複盤歐冠 :C羅梅西未能取勝 拜仁切爾西最穩定2025-07-09 16:47
This weird squid looks like it has googly eyes, guys2025-07-09 16:19
越南隊長:中國和阿曼都很強 目標取得比前兩輪更好的結果2025-07-09 15:50
熱刺前瞻 :孫興慜缺陣 凱恩帶隊衝擊歐會杯小組首勝2025-07-09 15:38
巴薩VS拜仁:後梅西時代的痛 紅藍還能刷新下限 ?2025-07-09 15:11
WhatsApp announces plans to share user data with Facebook2025-07-09 15:10
國足2將因訓練強度大身體不適 傷勢不嚴重可回歸合練2025-07-09 15:06