An international squad of scientists led past times Ivan Minchev of the Leibniz Institute for Astrophysics Potsdam (AIP) has found a agency to recover the nascency places of stars inwards our Galaxy. This is 1 of the major goals inwards the champaign of Galactic Archaeology, whose aim is to reconstruct the formation history of the Milky Way.
 |
| Left: H5N1 sample of most 600 stars situated rattling to a greater extent than or less the Lord's Day was used (approximate book shown past times arrow). Right: Using precise stellar historic menstruum together with atomic issue 26 content measurements, the stellar nascency places could live on recovered. Older stars were found to larn inwards preferentially from the inner parts of the disk (lighter coloured dots), spell younger ones (darker coluored dots) were born closer to their electrical current distance from the Galactic centre. The background picture shows a simulation of a galaxy similar to the Galaxy for perspective [Credit: I. Minchev (AIP)] |
To circumvent these obstacles, the scientists devised a agency of recovering the Galactic migration history using the ages together with chemic composition of stars every bit "Archaeological artifacts." They used the well-established fact that star formation inwards the Galactic disc progresses gradually outwards, next that stars born at a given lay at a item fourth dimension convey a distinct chemical-abundance pattern. Therefore, if the historic menstruum together with chemic composition (its atomic issue 26 content, for example) of a star tin live on measured rattling precisely, it becomes possible to lead infer its nascency lay inwards the Galactic disc without additional modeling assumptions.
The squad used a sample of most 600 solar-neighborhood stars observed amongst the high-resolution spectrograph HARPS mounted on the 3.6 k telescope of ESO's La Silla Observatory inwards Chile. Thanks to the rattling precise historic menstruum together with atomic issue 26 abundance measurements, it was found that these stars were born all across the Galactic disc, amongst older ones coming to a greater extent than from the cardinal parts.
Researches tin similar a shot role this method for calculation of nascency places fifty-fifty for stars non inwards the master copy sample. For example, given the historic menstruum of our Lord's Day of 4.6 billion years together with its atomic issue 26 content, it could live on estimated that the Lord's Day was born most 2,000 low-cal years closer to the Galactic oculus than it is currently located.
Minchev comments: "Once inwards the possession of nascency radii, a wealth of invaluable information could live on gained most the Galaxy past, fifty-fifty from this modest issue of stars amongst precise plenty measurements available to us at this time." Co-author Friedrich Anders adds: "In the nigh future, applying this method to the extremely high-quality information from the Gaia mission together with ground-based spectroscopic surveys volition permit much to a greater extent than exact measurements of the migration history and, thus, the Galaxy past."
The report is published inwards Monthly Notices of the Royal Astronomical Society.
Source: Leibniz-Institut für Astrophysik Potsdam [September 13, 2018]
Sumber http://archaeologynewsnetwork.blogspot.com
Buat lebih berguna, kongsi:
