The Beehive Cluster – Then & Now
The View from
GalileoÕs Telescope
Galileo
observed the Praesepe nebula in 1610. Praesepe, which is Latin for manger, had
been seen in the sky and recorded since ancient times, but before GalileoÕs observations,
was always described as a little cloud or mist. Through a telescope the true
nature of Praesepe was revealed – a cluster of sparkling stars. Praesepe
is now known as the Beehive Cluster.
Galileo counted 36 stars in the cluster, and observations supported
those he made of the Pleiades cluster and of the Milky Way. Before 1610, the known universe had
contained barely a few thousand stars.
GalileoÕs discovery of Òinnumerable fixed starsÓ showed the power of the
new telescope technology.
Left: GalileoÕs sketch of the stars in the
Beehive Cluster (Image Credit: Octavo Corp./Warnock Library)
What
did YOU See with MicroObservatory?
Can
you confirm GalileoÕs observation of the Beehive as a star cluster rather than
a nebula? If so, can you beat his
star count of 36? You have two advantages using MicroObservatory over GalileoÕs
Òspyglass.Ó The MicroObservatory telescopes are bigger, so can gather more
light from faint stars. The
telescopes are also equipped with an electronic detector that collects and
stores the light.
Above: Archive MicroObservatory image of the
Beehive.
To
see the Beehive in more detail, you may want to open your image in our MicroObservatory
image processing software. You
can also compare the Beehive with the Pleiades star cluster in the Galileo
activity.
The
Beehive - 400 years later
The Beehive is a cluster of
around 350 stars. At an age of 750
million years, the stars of the Beehive are much older than those in the
Pleiades cluster, and some are already in an advanced stage of evolution. For
stars, the bigger and brighter they are, the shorter their lifespan. The
biggest and brightest stars of the Beehive, which had been similar to those
that light up the Orion nebula (another of GalileoÕs objects), have long since
used up their nuclear fuel.
Because all the stars in the Beehive were born at the same time from the
same nebula, this cluster and others like it are very important laboratories
for astronomers to study the evolution and lifecycle of stars.
Above: A colorized image of the
Beehive. (Image credit: Sloan Digital Sky Survey)
Find
Out More
2009 is International Year
of Astronomy, chosen to commemorate the 400th anniversary of
GalileoÕs discoveries with the telescope.
Find out what else is happening by visiting these web sites:
The World site for International Year of
Astronomy.
The United States national site for
International Year of Astronomy.
NASAÕs International Year of Astronomy
website.
For more information on the
Sloan Digital Sky Survey, go to:
To take images of The
Pleiades star cluster and the Orion Nebula using microObservatory, go back to
the Galileo menu:
Take
a look at the full list of objects in MicroObservatoryÕs Galileo activity,
and see how our understanding has evolved over the last four centuries.