Proxima Centauri is a red dwarf star approximately 4.2 light-years
(3.97 × 1013 km) distant in the constellation of Centaurus. The star is
the nearest star to the Sun and is only 0.21 ly (15,000 ± 700
astronomical units) away from the binary star system Alpha Centauri.
Proxima Centauri's diameter is one-seventh that of the Sun; its mass is
about an eighth of the Sun's, and its average density is about 40 times
that of the Sun. Although it has a very low average luminosity, Proxima
Centauri is a flare star that undergoes random increases in brightness
because of magnetic activity; during a flare the star generates a total
X-ray emission similar to that produced by the Sun. The star's
relatively low energy production rate means that it will be a
main-sequence star for another four trillion years, or nearly 300 times
the current age of the universe. Searches for companions orbiting
Proxima Centauri have been unsuccessful; the detection of smaller
objects will require the use of new instruments, such as the proposed
Space Interferometry Mission. Whether a planet orbiting this star could
support life is disputed. Because of the star's proximity, it has been
proposed as a destination for interstellar travel.
Read the rest of this article:
<http://en.wikipedia.org/wiki/Proxima_Centauri>
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Today's selected anniversaries:
869:
The Fourth Council of Constantinople, the eighth Catholic Ecumenical
Council, was convened to discuss the patriarchate of Photios I of
Constantinople.
<http://en.wikipedia.org/wiki/Fourth_Council_of_Constantinople_%28Roman_Catholic%29>
1877:
After battling the U.S. Army for more than three months, retreating
over 1,000 miles across Oregon, Washington, Idaho, and Montana, and
enduring a five-day siege, Chief Joseph and his Nez Perce band finally
surrendered.
<http://en.wikipedia.org/wiki/Chief_Joseph>
1903:
Samuel Griffith became the first Chief Justice of Australia, while
Edmund Barton and Richard O'Connor became the first Puisne Justices of
the High Court of Australia.
<http://en.wikipedia.org/wiki/Samuel_Griffith>
1948:
The International Union for Conservation of Nature was founded at a
congress sponsored by UNESCO director Julian Huxley in Fontainebleau,
France.
<http://en.wikipedia.org/wiki/International_Union_for_Conservation_of_Nature>
1963:
The US suspended the Commercial Import Program, its main economic
support for South Vietnam, in response to oppression of Buddhism by
President Ngo Dinh Diem.
<http://en.wikipedia.org/wiki/Commercial_Import_Program>
1986:
The British newspaper The Sunday Times published former nuclear
technician Mordechai Vanunu's story revealing details of Israel's
nuclear capability.
<http://en.wikipedia.org/wiki/Mordechai_Vanunu>
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Wiktionary's word of the day:
peristalsis (n):
The rhythmic, wave-like contraction of the digestive tract that forces
food through it
<http://en.wiktionary.org/wiki/peristalsis>
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Wikiquote quote of the day:
There are things I can't force. I must adjust. There are times when the
greatest change needed is a change of my viewpoint.
--Denis Diderot
<http://en.wikiquote.org/wiki/Denis_Diderot>