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Astronomers Find Sun's Twin

Posted by simoniker on from the also-has-dreadlocks dept.

mroch writes "Space.com is reporting that astronomers may have found a solar twin -- a star almost exactly like our own Sun. Interesting tidbits from the article include: "The star, 18 Scorpii, sits about 47.5 light-years away in the constellation Scorpio, and has long-been suspected of being Sun-like. [...] The star burns slightly hotter than the Sun, at 5,789 degrees Kelvin compared to 5,777 degrees. It appears to rotate slightly faster than the Sun, taking 23 days to complete a rotation rather than the Sun's 25." It boggles my mind to think that we can measure temperature that exactly from 279,000,000,000,000 miles away, and that they are complaining over a 12-degree difference."

5 of 132 comments (clear)

  1. Measuring temperature at great distance by Frans+Faase · · Score: 5, Informative

    Distance actually does not matter with respect to the method used to measure the temperature, as long as you have enough light, and there is no disturbing medium in between. Both conditions seems to be met.

  2. Re:They use spectrometry to measure the heat by LittleBigLui · · Score: 5, Funny

    Yeah, there's much difference between a delta of 12 degrees kelvin and 12 degrees celcius. OTOH, you USians (and UKians?) with your funny measurements probably measure temperatures in ounces, feet or hands or something. :)

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    Free as in mason.
  3. Re:Measuring a star's temperature. by Dr.+GeneMachine · · Score: 5, Informative

    Doppler shift should not be a problem, you can always determine the shift rate from the known frequency of certain absorption lines in the spectrum and reference your spectrum to those lines.

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  4. Re:Degrees Kelvin, not Kelvin by ottawanker · · Score: 5, Informative

    From The U.S. Metric Association

    The kelvin (K) temperature scale is an extension of the degree Celsius scale down to absolute zero, a hypothetical temperature characterized by a complete absence of heat energy. Temperatures on this scale are called kelvins, NOT degrees kelvin, kelvin is not capitalized, and the symbol (capital K) stands alone with no degree symbol. [In 1967 the new official name and symbol for "kelvin" were set by the 13th General Conference on Weights and Measures (CGPM).]

  5. 50 closest, closest matches to the sun by nimblebrain · · Score: 5, Informative

    I like David Nash's list of 50 nearby sunlike stars within 50 light years.

    18 Scorpii is on there, as is the infamous Tau Ceti. 18 Scorpii was one of the four closest matches.

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    Binary geeks can count to 1,023 on their fingers :)