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Credit & Copyright: Stefan Seip (AstroMeeting.de)
Explanation:
What's that new star in the sky?
The star might appear new, but it's actually just the
variable star Mira
near its brightest.
Rolling your cursor over the above vertically compressed
image will identify the unusual star
Mira, a star that can change from practical invisibility
to one of the brighter stars on the sky over the course of a year.
Pictured above a castle in
Stuttgart,
Germany, last week,
red giant star
Mira appeared near its maximum brightness of
magnitude 2.
Although similar in mass to our Sun,
Mira tenuous and cool
atmosphere could extend out past the orbit of Mars, and achieve a
luminosity over 10,000 times greater than our Sun.
Mira is near the end of its life and its variability is somewhat erratic.
Details of Mira's variability are still
being researched, but the reason for Mira's pulsations are
thought related to periodic changes in the thickness of parts of Mira's atmosphere.
Recent high resolution images show that
Mira is not even round.
Mira lies 420
light years distant toward the
constellation of the Monster Whale
(Cetus).
Mira
will fade over the next 200 days, but climb back to naked-eye visibility early next
year.
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NASA Web Site Statements, Warnings, and Disclaimers
NASA Official: Jay Norris. Specific rights apply.
A service of: LHEA at NASA / GSFC
& Michigan Tech. U.
Based on Astronomy Picture
Of the Day
Publications with keywords: Mira - variable star
Publications with words: Mira - variable star
See also: