{"id":36934,"date":"2022-09-30T08:35:01","date_gmt":"2022-09-30T08:35:01","guid":{"rendered":"https:\/\/www.skyatnightmagazine.com\/?p=112368"},"modified":"2022-09-30T09:00:11","modified_gmt":"2022-09-30T09:00:11","slug":"astronomers-have-discovered-what-caused-betelgeuses-dimming-in-2019","status":"publish","type":"rss_feed","link":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/rss_feed\/astronomers-have-discovered-what-caused-betelgeuses-dimming-in-2019\/","title":{"rendered":"Astronomers have discovered what caused Betelgeuse\u2019s dimming in 2019"},"content":{"rendered":"

<\/p>

By Ezzy Pearson\n \t\t<\/p>

Published: Friday, 30 September 2022 at 12:00 am<\/p>

\n\n

Three years ago<\/span>, amateur astronomers around the world watched as the usually bright light of Betelgeuse<\/a> dimmed overnight and remained that way for several months.<\/p>\n

Now a group of astronomers have determined that Betelgeuse\u2019s dimming was caused by a piece of the star\u2019s atmosphere being ejected into space.<\/p>\n

\u201cWe\u2019ve never before seen a huge mass ejection of the surface of a star,\u201d says Andrea Dupree from the Center for Astrophysics, Harvard and Smithsonian, who led the study.<\/p>\n

Betelgeuse is a red giant star<\/a> over 1.6 billion kilometres wide \u2013 meaning if it replaced our Sun it would swamp Jupiter<\/a> and almost reach Saturn<\/a>.<\/p>\n

It has ballooned in size as it is approaching the end of its life and will eventually go supernova<\/a>.<\/p>\n

Though this is unlikely to happen for the next 10,000 years, it gives astronomers a unique view of a star in its final centuries.<\/p>\n

\"""\"<\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/picture><\/div>
After blowing its top, the red supergiant star\u2019s brightness dimmed dramatically behind the resulting dust cloud. Credit: NASA\/ESA\/Elizabeth Wheatley (STScI)<\/span><\/figcaption><\/div>\n

Over 200 years of observations have shown that the star\u2019s brightness slowly pulses according to a 400-day cycle, but the scale and speed of the 2019 dimming was unprecedented.<\/p>\n

Drawing together observations from all over the world, Dupree has determined that material bubbling up within the star blasted off a piece of the photosphere.<\/p>\n

The ejection had a mass several times that of our Moon \u2013 a colossal 400 billion times more than what our Sun typically gives off during coronal mass ejections.<\/p>\n

As this fractured piece cooled, it formed a dust cloud that blocked Betelgeuse\u2019s light from Earth, causing it to appear dimmer.\u00a0<\/span><\/p>\n

It also appears that Betelgeuse\u2019s 400-day brightness cycle has stopped, or at least paused.<\/p>\n

\"""\"<\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/picture><\/div>
These images, taken with the SPHERE instrument on ESO\u2019s Very Large Telescope, show the surface of the red supergiant star Betelgeuse during its unprecedented dimming, which happened in late 2019 and early 2020.<\/span><\/figcaption><\/div>\n

Spectral observations from the Hubble Space Telescope<\/a> taken by Dupree showed signs that this event and the star\u2019s attempts to rebuild its photosphere have disrupted the internal motions that drive the cycle.<\/p>\n

\u201cBetelgeuse continues to do some very unusual things right now; the interior is sort of bouncing,\u201d says Dupree.<\/span><\/p>\n

\u201cWe\u2019re left with something we don\u2019t completely understand. It\u2019s a totally new phenomenon that we can observe directly and can resolve surface details with Hubble. We\u2019re watching stellar evolution in real time.\u201d<\/span><\/p>\n

The team will continue to observe the red giant and hope to use the James Webb Space Telescope to watch as the cooling material moves away from the star.<\/span><\/p>\n

www.hubblesite.org\u00a0<\/span><\/span><\/strong><\/a><\/p><\/body><\/html>\n

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By Ezzy Pearson Published: Friday, 30 September 2022 at 12:00 am Three years ago, amateur astronomers around the world watched as the usually bright light of Betelgeuse dimmed overnight and remained that way for several months. Now a group of astronomers have determined that Betelgeuse\u2019s dimming was caused by a piece of the star\u2019s atmosphere […]<\/p>\n","protected":false},"author":24,"featured_media":36935,"template":"","categories":[1],"acf":{"readingTimeMinutes":"3"},"uagb_featured_image_src":{"full":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/09\/astronomers-have-discovered-what-caused-betelgeuses-dimming-in-2019.png",1500,750,false],"thumbnail":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/09\/astronomers-have-discovered-what-caused-betelgeuses-dimming-in-2019-150x150.png",150,150,true],"medium":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/09\/astronomers-have-discovered-what-caused-betelgeuses-dimming-in-2019-300x150.png",300,150,true],"medium_large":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/09\/astronomers-have-discovered-what-caused-betelgeuses-dimming-in-2019-768x384.png",768,384,true],"large":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/09\/astronomers-have-discovered-what-caused-betelgeuses-dimming-in-2019-1024x512.png",800,400,true],"1536x1536":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/09\/astronomers-have-discovered-what-caused-betelgeuses-dimming-in-2019.png",1500,750,false],"2048x2048":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/09\/astronomers-have-discovered-what-caused-betelgeuses-dimming-in-2019.png",1500,750,false]},"uagb_author_info":{"display_name":"importmanagerhub@sprylab.com","author_link":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/author\/importmanagerhubsprylab-com\/"},"uagb_comment_info":0,"uagb_excerpt":"By Ezzy Pearson Published: Friday, 30 September 2022 at 12:00 am Three years ago, amateur astronomers around the world watched as the usually bright light of Betelgeuse dimmed overnight and remained that way for several months. Now a group of astronomers have determined that Betelgeuse\u2019s dimming was caused by a piece of the star\u2019s atmosphere…","_links":{"self":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/rss_feed\/36934"}],"collection":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/rss_feed"}],"about":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/types\/rss_feed"}],"author":[{"embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/users\/24"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/media\/36935"}],"wp:attachment":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/media?parent=36934"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/categories?post=36934"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}