Astronomers have gotten their first look at exactly where most of today\u2019s stars were born. To do so, they used the National Science Foundation\u2019s Karl G. Jansky Very Large Array (VLA) and the Atacama Large Millimeter\/submillimeter Array (ALMA) to look at distant galaxies seen as they were some 10 billion years ago. <\/p>\n
At that time, the Universe was experiencing its peak rate of star formation. Most stars in the present Universe were born then.<\/p>\n
\u201cWe knew that galaxies in that era were forming stars prolifically, but we didn\u2019t know what those galaxies looked like, because they are shrouded in so much dust that almost no visible light escapes them,\u201d said Wiphu Rujopakam, of the Kavli Institute for the Physics and Mathematics of the Universe at the University of Tokyo and Chulalongkorn University in Bangkok, who was lead author on the research paper.<\/p>\n
Radio waves, unlike visible light, can get through the dust. However, in order to reveal the details of such distant \u2014 and faint \u2014 galaxies, the astronomers had to make the most sensitive images ever made with the VLA.<\/p>\n
The new observations, using the VLA and ALMA, have answered longstanding questions about just what mechanisms were responsible for the bulk of star formation in those galaxies. They found that intense star formation in the galaxies they studied most frequently occured throughout the galaxies, as opposed to much smaller regions in present-day galaxies with similar high star-formation rates.<\/p>\n
The astronomers used the VLA and ALMA to study galaxies in the Hubble Ultra Deep Field, a small area of sky observed since 2003 with NASA\u2019s Hubble Space Telescope (HST). The HST made very long exposures of the area to detect galaxies in the far-distant Universe, and numerous observing programs with other telescopes have followed up on the HST work.<\/p>\n
\u201cWe used the VLA and ALMA to see deeply into these galaxies, beyond the dust that obscured their innards from Hubble,\u201d said Kristina Nyland, of the National Radio Astronomy Observatory (NRAO). \u201cThe VLA showed us where star formation was occurring, and ALMA revealed the cold gas that is the fuel for star formation,\u201d she added.<\/p>\n
\u201cIn this study, we made the most sensitive image ever made with the VLA,\u201d said Preshanth Jagannathan, also of NRAO. \u201cIf you took your cellphone, which transmits a weak radio signal, and put it at more than twice the distance to Pluto, near the outer edge of the solar system, its signal would be roughly as strong as what we detected from these galaxies,\u201d he added.<\/p>\n
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The study of the galaxies was done by an international team of astronomers. Others involved include James Dunlop of the University of Edinburgh and Rob Ivison of the University of Edinburgh and the European Southern Observatory. The researchers reported their findings in the Dec. 1 issue of the Astrophysical Journal<\/em>.<\/p>\n ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada), NSC and ASIAA (Taiwan), and KASI (Republic of South Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI\/NRAO and NAOJ.<\/p>\n The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.<\/p>\n","protected":false},"excerpt":{"rendered":" Astronomers have gotten their first look at exactly where most of today\u2019s stars were born. To do so, they used the National Science Foundation\u2019s Karl G. Jansky Very Large Array (VLA) and the Atacama Large Millimeter\/submillimeter Array (ALMA) to look at distant galaxies seen as they were some 10 billion years ago. At that time, […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[],"tags":[],"class_list":["post-60138","post","type-post","status-publish","format-standard","hentry"],"_links":{"self":[{"href":"http:\/\/healthmedicinet.com\/news\/wp-json\/wp\/v2\/posts\/60138","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/healthmedicinet.com\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/healthmedicinet.com\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/healthmedicinet.com\/news\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/healthmedicinet.com\/news\/wp-json\/wp\/v2\/comments?post=60138"}],"version-history":[{"count":0,"href":"http:\/\/healthmedicinet.com\/news\/wp-json\/wp\/v2\/posts\/60138\/revisions"}],"wp:attachment":[{"href":"http:\/\/healthmedicinet.com\/news\/wp-json\/wp\/v2\/media?parent=60138"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/healthmedicinet.com\/news\/wp-json\/wp\/v2\/categories?post=60138"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/healthmedicinet.com\/news\/wp-json\/wp\/v2\/tags?post=60138"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}