Enjoy our starry night sky
Be a considerate neighbor: Reduce nighttime glare.
Shield your outside lights downward, so no glare goes up to dull
the night sky (or into your neighbor’s windows) and enjoy
the beautiful, stars above.
June 2008 Night Sky
THE LION SLEEPS TONIGHT
In the west, an hour after sunset, Leo the Lion—the king of
beasts—roars. On June evenings, Leo slowly wanders toward
the western horizon followed by the lion cub Leo Minor. Leo follows
two other zodiac star groupings. The Gemini Twins are close to the
west-northwest horizon; Cancer is between the Twins and Leo in the
Mythology tells us that first-up on Hercules’ list of endeavors
was the task of killing the Nemean Lion. Nemean was a giant beast
that roamed the hills of the Peloponnesian villages, causing death
and destruction. This beast was strong and powerful. At first, Hercules
attempted to kill the lion using his arrows, but they bounced off
of the lion’s thick hide. Next, Hercules tried using his sword,
but it bent in two. Hercules had to wrestle the beast. After a fierce
battle, Hercules finally killed the beast by choking it to death.
Hercules then wrapped the pelt of the lion around his body to protect
himself for his second labor, killing the poisonous sea serpent
Hydra. The lion found its way to the heavens to commemorate the
great battle with Hercules.
Leo is full of interesting stars, the brightest of which is Regulus,
meaning “little king.” It is a blue-white star about
77.5 light-years away. Regulus is a young star, about 3.5 times
heavier than our Sun. It is spinning extremely rapidly, making a
complete revolution every 15.9 hours, which causes it to have a
highly flattened shape. If this star rotated much faster, it would
rip itself apart. There is a pair of faint companion stars orbiting
Regulus. The pair has an orbital period of over 130,000 years at
a distance of some 4,200 astronomical units (one astronomical unit
is the distance between Earth and the Sun).
Denebola is the tail star of Leo. It is a relatively young star
with an age estimated at less than four hundred million years. Astronomers
believe there must be a debris disk of cool dust in orbit around
it, which either is or could form planets. Seen through a telescope,
there appears to be an orange companion to Denebola, but in reality,
the other is much further away and not gravitationally bound.
The binary Algieba (the lion’s mane), is a magnificent pair,
which consists of an orange-red giant and a yellow giant. A small
telescope is sufficient to image both stars. An unrelated fifth
mag star, 40 Leo, can be seen next to them through binoculars. Remember,
bigger magnitude values mean dimmer stars.
Look for these other multiple stars in Leo. Another optical double
is tau Leo, a fifth magnitude star. Its seventh magnitude companion
can be seen with binoculars. Using a low power telescope, 54 Leo
can easily be resolved into a pair of 4.5 magnitude and 6.3 magnitude
stars. Adhafera is an optical triple. Seen through binoculars, this
star seems to have two companions of sixth magnitude, but they are
not physically related together.
There is a long period red giant variable star called rho Leo
you can study over the course of a year. Its brightness varies from
4.4 to 11.6 magnitude, with a period of about 313 days. It is found
in the Lion’s foreleg.
So, get outside on the warm June evenings, turn off your outdoor
lights, and enjoy the spectacular show we call the night sky. Who
knows—you might even hear Leo roar.
THE PLANETS AND THE MOON
• The best chance to find Mercury is late in June. Look in
the east about thirty minutes before sunrise.
• Venus, too, will be low in the east at sunrise, but it is
bright enough to spot.
• Mars will be setting in the west about midnight this month,
making it a tempting target high in the western sky after sunset.
On the evening of the 7th, look for the red planet two degrees above
and to the right of the waxing Moon.
• Jupiter is rising in the east at about 11:00 p.m. early
in the month. By the end of the month, look for the planet to be
rising at about 10:00 p.m. Look low in the southeast about two hours
after sunset on the 19th. You’ll find Jupiter six degrees
to the Moon’s left.
• High in the west after sunset is Saturn, above Mars. It
will be setting after midnight most of the month. The Moon will
be five degrees below Saturn on the 8th.
• The Moon will be exactly new at 1:23 p.m. on the 3rd. The
Full Moon will happen at 11:30 a.m. on the 18th.
• Summer officially begins at 5:59 p.m. MDT on the 20th.
The International Space Station keeps growing, and with every addition,
it looks brighter in the night sky. Though the times in the chart
(below) may change by a few minutes from those predicted, June is
a great time to spot this orbiting outpost.
If you have a question or comment for Charlie, you may email him