Save our
starry night skies
Be a considerate neighbor: Reduce nighttime glare.
Shield all your outside lights downward (or turn them off completely)
and enjoy the beautiful, starry night sky.
October night sky—Next stop—Luna
—CHARLIE CHRISTMANN
With the International Space Station on track for completion
sometime around 2010, NASA is talking up its next great adventure—the
Moon. The U.S. space agency wants to put men and women back on the
Moon for a long-term stay. With all of the hype coming from NASA,
who could resist writing about it? So, here are some Moon facts:
FACT 1: The place to start is in the beginning, some 4.5 billion
years ago. Planetary scientists believe that Earth Mark One formed
around the Sun in about the same location we reside today, but Earth
Mark One was without a moon. That Earth also had another close neighbor
about the size of Mars. These two planetary objects crossed paths
and collided. The shock of the impact ripped away the outer layers
of both Earth Mark One and the impacting object. Think about a compact
car flying the wrong way down a highway and colliding head-on with
an SUV. Glass, trim, and hubcaps fly everywhere, but the bodies
of the two cars remain hopelessly entangled. The iron cores of both
bodies melded into Earth’s core, while the outer layers were
flung off into orbit. Much of the material soon rained down in a
torrent of meteors; however, some of the stuff stayed in orbit,
coalesced and created the Moon. Earth Mark Two cooled and eventually
formed what we see today.
FACT 2: You may have noticed the Moon always shows the same face
to Earth. We never see the back side. Long ago, the Earth’s
gravitational effects slowed the Moon’s rotation about its
axis. Once the Moon’s rotation slowed enough to match the
time it takes to make one orbit, the effect stabilized. Many of
the moons around other planets behave similarly.
FACT 3: The Moon most likely protected the Earth many times from
the impacts of large space rocks. Just look at its heavily cratered
surface. The most intense pummeling probably happened between 4.1
billion and 3.8 billion years ago. The scars have not eroded much
for two main reasons: the Moon is not geologically active and it
has virtually no atmosphere. On the Moon, there are no major earthquakes
(moonquakes?), nor active volcanoes. Nor are there floods or sand
storms to erode the surface. Even today, astronomers watch meteorites
impact the lunar surface in their telescopes.
FACT 4: It may not be geologically active, but there are moonquakes
on the Moon. Apollo astronauts left behind several seismometers
during their visits. The small quakes originate several miles below
the surface. They are thought to be caused by the gravitational
pull of Earth, causing “tides” in the surface. Astronomers
and satellites in orbit have spotted gas escaping the surface of
the Moon. No one is really sure what generates the gas, but the
moonquakes probably cause cracks and allow small pockets to escape.
FACT 5: Tides on Earth are caused mostly by the Moon. The effect
of the Sun is much smaller. The Moon’s gravity pulls on Earth’s
oceans. High tide aligns with the Moon as Earth spins underneath.
Another high tide occurs on the opposite side of the planet because
gravity pulls Earth toward the Moon more than it pulls the water.
At full Moon and new Moon, the Sun, Earth, and Moon are lined up,
producing higher than normal tides. When the Moon is at first or
last quarter, smaller neap tides form. When the Moon is closest
to Earth (called its perigee), spring tides are even higher, and
they’re called perigean spring tides. All this tugging has
another interesting effect. Some of Earth’s rotational energy
is stolen by the Moon, causing our planet to slow down by about
1.5 milliseconds every century. But, as the Moon steals energy from
us, it gains energy. It uses that energy to increase the orbital
distance between the Earth and the Moon at a rate of about 1.5 inches
each year. When it formed, the Moon was about 22,500 miles above
the Earth; today, it sits an average of 280,000 miles overhead.
Now, with your new-found knowledge of our closest celestial neighbor,
perhaps you would like to make a trip there. Here’s your chance.
NASA is hiring astronauts for missions to the ISS and the Moon.
Applications are being accepted from September 18, 2007 through
July 1, 2008 for the Astronaut Candidate Class of 2009. Interested?
Find out more at www.nasa.gov/astronauts/recruit.html.
THE PLANETS AND THE MOON
• Mercury will be hiding in the sunlight until late in the
month. Look low in the east the last week of October about an hour
before sunrise for a glimpse.
• No one can miss Venus shining at a brilliant 4.5 magnitude.
It rises in the east at about 3:30 am.
• Mars rises in the east around 11:00 p.m. this month. The
Moon and Mars have a conjunction on the 2nd and the 30th.
• Jupiter is low in the southern sky at sunset; progressing
further west as the night goes on, setting at about 9:30 p.m. The
Moon joins Jupiter and Antares low in the west forty-five minutes
after sunset on the 15th.
• Rise early to find Saturn. It rises in the east at about
4:00 a.m. early in the month and 2:30 a.m. late in the month. On
the 7th, look for a spectacular grouping with the Moon, Saturn,
Venus, and the star Regulus. Look for Saturn to the left of the
Moon, Venus to the upper right, and Regulus above the Moon an hour
before sunrise.
• The Moon is new on the 10th at 11:01 MDT and full on the
26th at 5:52 a.m. MDT. Halloween night promises to be brightly bathed
in moonlight this year. Also on the 26th, the Moon reaches perigee,
its closest point in its orbit around the Earth at 221,677 miles.
Apogee is on the 13th at 252,581 miles overhead.
If you have a question or comment for Charlie,
you may email him at k5cec@yahoo.com.
Star Party telescopes look to dark skies of Placitas
The annual Placitas Star Party, hosted by Las Placitas Association
and the Albuquerque Astronomical Society, will be held on Saturday,
October 6 at sunset (approximately 6:45 p.m.) at the Homestead Village
Shopping Center in Placitas. Well-informed members of the New Mexico
Astronomical Society will be there with their telescopes to describe
in detail the night skies to visitors. They welcome questions. Among
the sights to be seen in the night sky will be Jupiter and its four
bright moons in the early part of the evening, and the Milky Way
Galaxy between 8:00 and 9:00 p.m. This is a free family event to
promote dark skies in the community. All are welcome. For additional
information, call Reid Bandeen at 867-5477.
Governor Richardson proclaims “New Mexico
Dark Sky Appreciation Night”
Governor Bill Richardson has proclaimed September 14 as “New
Mexico Dark Sky Appreciation Night” in order to bring attention
to the beauty of New Mexico’s night sky and to educate the
public about the importance of protecting the dark night sky from
light pollution.
“New Mexico’s dark night sky is a precious resource
that should be enjoyed and must be protected,” said State
Parks Director Dave Simon. “Every household and business can
help by reducing excessive outdoor nighttime lighting—and
[can] save energy at the same time.”
In conjunction with the Governor’s proclamation, New Mexico
State Parks hosted a number of star parties in September statewide
through its “Reach for the Stars” program.
Initiated in 2004, the New Mexico State Parks’ “Reach
for the Stars” program is a multi-faceted effort that promotes
the night sky as a valuable educational, tourism, and economic resource,
while encouraging the protection of New Mexico’s night sky
from light pollution. The program includes over one hundred night
sky events per year, staff and volunteer training, investment in
park astronomy observatories, public education about light pollution
prevention, and reduction of light pollution within state parks.
In 2006, the program won the New Mexico Heritage Preservation Alliance
(NMHPA)’s “Nebula Award,” which recognizes extraordinary
innovation in a program, project, or product that contributes significantly
to the protection and preservation of New Mexico’s night skies.
Since 2005, observatories have been constructed at two state parks
in New Mexico—City of Rocks and Clayton Lake State Parks.
The Division also retrofitted Oasis State Park with efficient outdoor
lighting that protects the night sky and is installing innovative
solar-powered LED lighting along park trails to save energy and
reduce light pollution.
For more information on the New Mexico State Parks’ “Reach
for the Stars” program, or to see a schedule of star parties
throughout the year, visit www.nmparks.com,
or contact Steve Cary at (505) 476-3386 or steve.cary@state.nm.us.
Also in September, the NMHPA and El Valle Astronomers hosted the
first “Southwest Night Sky Conference” in Taos, which
included presentations on night sky protection policies and progressive
lighting technology, as well as star viewing through telescopes.
For information on the NMHPA and next year’s conference, visit
www.nmheritage.org
or call (505) 989-3696. |