The mystery of the star's light source

Scientists at the University of Toronto and the University of British Columbia helped reveal the 'birthplace' of ancient stars using a 2-ton telescope on a balloon the size of a 33-storey building. .

After two years of data analysis from the Telescope project near the millimeter-wide telescope (BLAST), an international group of astronomers and astrophysics from Canada, the United States, and the Kingdom He revealed in the April 8 issue of Nature that half of the stars' light in the universe comes from young star-forming galaxies several billion light-years away.

UBC astronomer Douglas Scott said: 'The familiar optical images of the night sky contain objects that are very beautiful and attractive. However, those pictures still lack half the panorama of the universe's star-forming history. '

Barth Netterfield, a cosmologist from the Department of Astronomy and Astrophysics at the University of Toronto, said: 'Stars are formed in clouds of gas and dust. Dust absorbs starlight, obscures young stars. The brightest stars in the universe often have the shortest life cycle and many of them never leave where they were born . However, warm dust glows at near-infrared and near-millimeter wavelengths - human eyes cannot see, but ultra-sensitive heat detectors on BLAST can be observed.

UBC Professor Mark Halpern commented: 'The history of star formation in the universe is written in our data. It's really beautiful and attractive. '

In the 1990s, NASA's COBE satellite detected a near-millimeter light region, known as the Far Infrared Background. This radiation is thought to come from a warm dusty area covering young stars, but the nature of the galaxy that contains the dust is still a mystery at the time.

The Nature journal study incorporates close-millimeter observations of BLAST at a wavelength of about 0.3mm - between infrared and ultra-short wavelengths - with shorter infrared wavelength data from Spitzer's Space Telescope NASA to determine that the Far Infrared Background came from a galaxy far away. This is the answer to a decades-long mystery about the origin of the radiation.

In addition to directing data analysis, Canadian scientists are also involved in developing the BLAST project. The aluminum balloon basket is designed to protect telescopes, planets and data on airships when landing. The engine system controls a 2,000 kilogram payload with a 2-meter-diameter telescope - the largest of all telescopes - with an accuracy of 1/100 of a degree. The complex machine system controls and records nearly 1,000 sensors while the software - nearly 300,000 lines of code - controls the payload in a flight lasting 39 kilometers.

Half the light of stars in the Universe originates from a galaxy that forms young stars a few billion light years away. (Photo: BLAST)

Bringing the telescope up above the atmosphere allows BLAST's team to look deep into the distant universe at an impossible wavelength from the ground, and detect galaxies covered by dust, a place that hides a half starlight in the Universe.

Chapin said: 'Over the past decade, near-millimeter telescopes have produced some' black and white 'photographs that are no bigger than the size of a fingernail. In just 11 days of flight, BLAST has made great strides, producing color photographs of your hand's size. '

BLAST acts as a 'pathfinder' for the SPIRE device (Spectrophotometer and photometric receiver) on Herschel satellite. Using the same detector as SPIRE, BLAST provided the first priceless images in the 'near-millimeter' sky .

Netterfield, a project participant with University of Toronto colleagues, Dean Peter G. Martin, Macro graduate student P. Viero, and Enzo Pascale, said: 'BLAST has brought a new perspective on the universe. . The data we collect is a precursor to the emergence of new discoveries, from star formation to the evolution of distant galaxies. '

BLAST is also capable of studying the earliest stages of star formation in the Milky Way galaxy. The BLAST project also published a study, in the Astrophysical Journal, which is the largest survey of the earliest stages of star formation. This study records the existence of a group of cold gas and dust clouds, with temperatures lower than -260 degrees Celsius. The icy core, which has existed for millions of years, is the star-forming place.

Marsen said: 'In the past 9 years, I have followed the BLAST project from Vancouver to Toronto, Philadelphia, New Mexico, Texas, North Sweden and Antarctica. It was great that we were finally able to publish the results. These results are an important step in astronomy. '

Halpern said: 'The scientific success of Canadian PhD students and doctors working in the BLAST project is very impressive and rewarding'.

BLAST collaborators include: Mark Devlin, Jeff Klein, Marie Rex, Christopher Semisch and Matthew DP Truch (University of Pennsylvania); Mark Halpern, Edward L. Chapin, Gaelen Marsden, Henry Ngo and Douglas Scott (University of British Columbia); C. Barth Netterfield, Peter G. Martin, Marco P. Viero, Donald V. Wiebe (University of Toronto); Enzo Pascale, Peter AR Ade, Matthew Griffin, Peter C. Hargrave, Philip Mauskopf, Lorenzo Moncelsi and Carole Tucker (Cardiff University); James J. Bock (Jet Propulsion Laboratory); Gregory S. Tucker (Brown University); Itziar Aretxaga and David H. Hughes (Instituto Nacional de Astrofısica Optica y Electronica, Mexico); Joshua O. Gundersen and Nicholas Thomas (University of Miami); Luca Olmi (Puerto Rico University, Rio Piedras Campus and INAF), and Guillaume Patanchon (Laboratoire APC, Paris).

BLAST Experiment is National Aeronautics and Space Agency, the Office of Polarity National Science Foundation, Canadian Space Agency, Canadian Natural Science Research Council, and Science and Technology Council. UK funding; with help from Magnelli, WestGrid and SIMBAD and NASA / IPAC data systems, Columbia Science Airship Facility, Ken Borek Air Company, and climbers from McMurdo Station, Antarctica .

Refer:
Devlin et al.Over half của far xa không gian cơ sở dữ liệu cần đến từ galaxies tại z lớn hơn hoặc bằng bằng 1.2.Nature, 2009;458 (7239): 737 DOI: 10.1038 / nature07918