NASA instruments
measure energy in
the night sky across
the electromagnetic
spectrum. By looking
at the sky in wave-
lengths beyond the
visible spectrum,
scientists can see
a more complete
picture. This helps
them study questions
like ‘how was the
universe formed’ and
‘how is it changing.’
Orion is one of the most widely recognized of all the 89 constellations in
the sky. It is also one of the oldest known to humans. The Ancient Egyptians
called it Osiris as long ago as 2000 BC!
The brilliant stars that make up this rectangular star pattern seem to be
close-by because they are so bright, but in fact they are very far away.
Astronomers measure distances using a unit called the light year, which
equals about 5.9 trillion miles (9.5 trillion km), or 63,240 times the
distance from Earth to the Sun!
TRY THEsE cAlculATIONs!
The bright star in Orion called Betelgeuse is located 650 light years from
Earth.
What is this distance in miles or kilometers�
Betelgeuse is expected to blow up as a supernova sometime in the next million
years. Suppose this happened in the year 3000 AD.
In what year would someone on
Earth see this explosion� �o online to �ind the answers, littleBits.cc/starchart
The con st� lati on �rion .
The se images show features th at can not be seen in
visible light
but appear brightly in
in�rared
Visible light image: Akira Fujii
Infrared image: Infrared
Astronomical Satellite
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