Saturday: Saturn
is nearly three fists held upright and at arm’s length above the
south-southeast horizon. With the naked eye, and through binoculars, Saturn
looks to be a dull orange color. This is because of the different gasses in the
atmosphere. But a close up view reveals even more colors - brown, yellow, and
even blue – emphasizing different gases, cloud layers, and wind patterns. For a
true-color close-up view of Saturn and Titan, its largest moon, go to http://goo.gl/vqI3Z.
Sunday: The
questions who, what, where, and when can only be asked with a “W”. At 11 p.m.,
the W-shaped constellation Cassiopeia is about two fists above due north. The
middle star in the W was used as a navigation reference point during the early
space missions. The American astronaut Gus Grissom nicknamed the star Navi, his
middle name Ivan spelled backwards. After he died in the Apollo 1 fire, the star
name was kept as a memorial.
Monday:
Mercury, Venus, and Jupiter are clustered low in the west-northwest sky after
sunset for most of the week. At 9 p.m. tonight, Jupiter is about a fist above
the horizon, Venus is a half a fist above the horizon, and Mercury is to the
lower right of Venus. As the week goes on, Venus and Mercury move upward in the
sky and Jupiter moves downward. By Thursday, the rapidly moving Mercury has
passed up Venus. By next week, both Venus and Mercury are above Jupiter.
Tuesday: Spica
remains less than a half a fist to the left of the moon throughout the night.
Wednesday:
Saturn remains about a half a fist or less above the moon throughout the night.
Thursday:
When it is sitting low in the western sky, many people mistake the star Capella
for a planet. It is bright. It has a slight yellow color. But, Capella is
compelling on its own. It is the fourth brightest star we can see in
Ellensburg. It is the most northerly bright star. It is a binary star
consisting of two yellow giant stars that orbit each other every 100 days. At
10 p.m., Capella is two fists above the northwest horizon. If you miss it
tonight, don’t worry. Capella is the brightest circumpolar star meaning it is
the brightest star that never goes below the horizon from our point of view in Ellensburg.
Friday: Late
spring and early summer is a good time to look for star clusters. Last week,
you learned about M3, the third object cataloged by French astronomer Charles
Messier over 200 years ago. One of the best clusters is the globular cluster in
the constellation Hercules, also called M13. (Hummm. Guess what number that
object is in Messier’s catalog.) Globular clusters are compact groupings of a
few hundred thousand stars in a spherical shape 100 light years across. (For
comparison, a 100 light year diameter sphere near out Sun would contain a few
hundred stars.) The globular cluster in Hercules is six fists above due east at
11 p.m. First find Vega, the bright bluish star about four fists above the
east-northeast horizon. Two fists to the upper right of Vega is a keystone
shape. Aim your binoculars at the two stars that form the uppermost point of
the keystone. The globular cluster is one third of the way south of the
uppermost star on the way to the rightmost star of the keystone. It looks like
a fuzzy patch on the obtuse angle of a small obtuse triangle. If you don’t know
what an obtuse angle is, you should not have told your teacher, “I’ll never
need to know this stuff”.
The
positional information in this column about stars and planets is typically
accurate for the entire week.
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