That means that, if there are planets around the star, scientists could get a really detailed look at them. Vega, for example, rotates around its axis once every 16 hours—much faster than the sun with a rotational period that clocks in at 27 Earth days. To take on that game of celestial hide-and-seek, he and colleagues pored through roughly 10 years of data on Vega collected by the Fred Lawrence Whipple Observatory in Arizona.
The search may have paid off, said Hurt, who began the study as a summer research fellow working for Quinn at the CfA. That close to Vega, he added, the candidate world might puff up like a balloon, and even iron would melt into gas in its atmosphere. Hurt noted that the easiest way to look for it might be to scan the stellar system directly to look for light emitted from the hot, bright planet.
Subscribe to CUBT. Vega is a slightly bluish, white main sequence dwarf star of spectral and luminosity type A0 V, like Sirius. Although the star was estimated previously to have 2. Vega may also have 2. Like Sirius, however, Vega radiates much more in ultraviolet wavelengths than Sol, and, not surprisingly, the European Space Agency has used ultraviolet spectral flux distribution data to determine stellar effective temperatures and surface gravities, including those of Vega.
The star may be about only 63 percent as enriched as Sol with elements heavier than hydrogen "metallicity" based on its abundance of iron D. Gigas, , but more recent findings on Vega's mild underabundance of metals can be found in Ilijic et al, On the other hand, its iron metallicity has been measured anywhere from four to percent of Sol's Cayrel de Strobel et al, , page Previously estimated to be only around to million years old Maeder and Meynet, , more recent estimates of its mass indicate an age of around to million years Ken Croswell, Science Now , December 3, and Monnier et al, As Vega is so much bigger and hotter than Sol, however, the star will exhaust its core hydrogen after only another million years or so for a total life of around a billion years and turn into a red giant or Cepheid variable before puffing away its outer layers to reveal a remnant core as a white dwarf.
The star is a rapidly rotating star whose apparent "pole-on" view from Earth distorts its various stellar characteristics Aufdenberg et al, ; and Gulliver et al, Jason P. Vega rotates so fast that it is cooler as well as wider at its equator than at its poles more. On January 10, , astronomers using the infrared Center for High Angular Resolution Astronomy CHARA Array announced that Vega rotates so fast at around 91 percent of its "break-up rate" that it is cooler as well as 23 percent wider along its equator than at its poles due to the gravitational effect of its "middle bulge" NOAO press release ; AAS session summary ; and Aufdenberg et al, Although our Sun, Sol, takes around The observations are consistent with the hypothesis that Vega is viewed with its pole of rotation pointing toward Earth first proposed by astronomer Richard O.
Gray , so that the relatively cool equator corresponds to the darker " limb of the star " and heightens the gravity-darkening effect. Vega is a Delta Scuti type of pulsating variable star over 0. In , an orbiting satellite called IRAS discovered far more infrared radiation -- which has waves longer than red light -- coming from the Vega than expected for small interstellar dust grains found around young, early-type stars Harvey et al, The radiation is coming from a huge circular shell of dust surrounds the star extending outwards to AU in radius, much like those that encompass Fomalhaut, Beta Pictoris, and Denebola van der Bliek et al, In early , astronomers announced that they had discovered an asteroid belt surrounding Vega , suggesting the possibility of planets within the rocks' midst.
The layout which resembled that found near the star Fomalhaut suggests that there are two areas: an outer region with icy asteroids and a region closer to the star, where warmer space rocks reside.
While the primary mission of TESS is to search for exoplanets, the satellite will also search for signs of star variability. TESS's examination of Vega and similar stars will help scientists learn more about the early stages of star evolution.
Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at: community space. Elizabeth Howell is a contributing writer for Space. She is the author or co-author of several books on space exploration. Start Vega: a Reference Star. Science Physics. Astronomy Discovery Science Space. Estimated reading time Time 4 to read. Vega in figures: It is some 25 light years from the Solar System.
It has a diameter 2. Its real luminosity is nearly 40 times that of the sun, so if it replaced our Sun, it would burn us up in a few thousands of a second.
Both Vega and the Sun have reached around half their lives, although Vega will die sooner, as it consumes its energy quicker as it is more massive.
Vega is much younger than the sun it is a tenth of its age : 4, million years. Do you want to stay up to date with our new publications? Receive the OpenMind newsletter with all the latest contents published on our website Find out more here.
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