GRB 970508 was a gamma-ray burst (GRB) detected on May 8, 1997, at
21:42 UTC. A gamma-ray burst is a highly luminous flash of gamma rays,
the most energetic form of electromagnetic radiation, which is often
followed by a longer-lived "afterglow" emitting at longer wavelengths
(X-ray, ultraviolet, optical, infrared, and radio). GRB 970508 was
detected by the Gamma Ray Burst Monitor on the Italian–Dutch X-ray
astronomy satellite BeppoSAX. Astronomer Mark Metzger determined that
GRB 970508 occurred at least 6 billion light years from Earth; this was
the first measurement of the distance to a gamma-ray burst. Until this
burst, astronomers had not reached a consensus regarding how far away
GRBs occur from Earth. Some supported the idea that GRBs occur within
the Milky Way, but are visibly faint because they are not highly
energetic. Others concluded that GRBs occur in other galaxies at
cosmological distances and are extremely energetic. Although the
possibility of multiple types of GRBs meant that the two theories were
not mutually exclusive, the distance measurement unequivocally placed
the source of the GRB outside the Milky Way, effectively ending the
debate. GRB 970508 was also the first burst with an observed radio
frequency afterglow.
Read the rest of this article:
<http://en.wikipedia.org/wiki/GRB_970508>
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Today's selected anniversaries:
1782:
Running out of medical supplies to combat the disease scurvy, British
troops surrendered to an allied Franco-Spanish force, ending the
latter's invasion of the Island of Minorca in the Mediterranean Sea.
<http://en.wikipedia.org/wiki/Invasion_of_Minorca%2C_1781>
1783:
The first of five strong earthquakes hit the region of Calabria in
present-day southern Italy, killing more than 32,000 people over a
period of nearly two months.
<http://en.wikipedia.org/wiki/1783_Calabrian_earthquakes>
1862:
Domnitor Alexander John Cuza merged his two principalities, Wallachia
and Moldavia, to form the Danubian Principalities.
<http://en.wikipedia.org/wiki/Alexander_John_Cuza>
1885:
Leopold II of Belgium established the Congo Free State as his personal
possession in Africa through his organization International African
Association and his private army, the Force Publique.
<http://en.wikipedia.org/wiki/Congo_Free_State>
1917:
The U.S. Congress passed the Immigration Act of 1917 with an
overwhelming majority, overriding U.S. President Woodrow Wilson's veto,
banning, among others, immigration from nearly all of South and
Southeast Asia.
<http://en.wikipedia.org/wiki/Immigration_Act_of_1917>
1958:
A Mark 15 nuclear bomb now known as the Tybee Bomb disappeared off the
shores of Tybee Island, Georgia, U.S. after it was jettisoned during a
practice exercise when the bomber carrying it collided in midair with a
fighter plane.
<http://en.wikipedia.org/wiki/Tybee_Island_B-47_crash>
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Wiktionary's word of the day:
affront (v):
1. To insult intentionally, especially openly; to offend purposefully.
2. To meet defiantly; to confront.
3. (obsolete) To meet or encounter
face to face
<http://en.wiktionary.org/wiki/affront>
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Wikiquote quote of the day:
All progress has resulted from people who took unpopular positions. All
change is the result of a change in the contemporary state of mind.
Don't be afraid of being out of tune with your environment, and above
all pray God that you are not afraid to live, to live hard and fast. To
my way of thinking it is not the years in your life but the life in
your years that count in the long run. You'll have more fun, you'll do
more and you'll get more, you'll give more satisfaction the more you
know, the more you have worked, and the more you have lived. For yours
is a great adventure at a stirring time in the annals of men.
--Adlai Stevenson
<http://en.wikiquote.org/wiki/Adlai_Stevenson>
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