Adopt this resolution in the New Year:
“I will protect the night sky so my neighbors and I can see the stars, comets, and planets by being be sure that my outside lights are shielded downward, so there is no upward glare ... at all.”
January 2005 night skies
If you feel a bit warmer on New Year's Day, or the Sun seems a bit brighter today, the end is not near. Earth is at perihelion, which is the closest point in our elliptical orbit to the Sun. Because we are about 3.1 million miles closer to the Sun than we were at aphelion in July, it is about 7 percent brighter than it was in July. In this part of our orbit, the Earth is also moving its fastest, about 67,800 miles per hour.
Comet Machholz will be at its closest to Earth on January 5 and 6, when it will be thirty-two million miles away. The comet is quickly moving higher into the night skies and should continue to brighten through early January. Beginning in January, the comet will be in the constellation Taurus and moving toward Perseus. Through binoculars the comet will appear as a fuzzy ball and may have a slight faint tail. As it looks now, unless something spectacular happens, this comet will not be visible to the naked eye except under the darkest skies.
As long as we are in the area, Perseus is an interesting night-sky object, nearly overhead about 9:00 p.m. Perseus represents the Greek god who slew the monster Medusa. One of the best-known stars, Algol, in the night sky is located in Perseus.
While Algol may not be the brightest star of this constellation, it definitely is the most famous. Algol (from Arabic al-ghul, which means ghoul or demon) represents the eye of Medusa. This star has the unusual property of having regular variations in brightness. Its brightness changes regularly between a magnitude 2.3 and 3.5 over a period of two days, twenty hours, and forty-nine minutes. Algol is actually two stars in a close orbit about one another. When the second, dimmer star passes in front of its larger, brighter companion once per orbit, the amount of light reaching earth is decreased, followed by an increase as the companion moves out of the way. This duo lies at a distance of only ninety-three light-years from the Sun.
Mirphak, a super-giant with an apparent brightness of 1.79 magnitude, is the brightest star of this constellation. This star is much further away than Algol at a distance of 590 light-years. Its brightness is attributed to the fact that it is five thousand times brighter and sixty-two times larger in diameter that our Sun.
There are several open star clusters in Perseus that are interesting when viewed with binoculars or a small telescope. NGC 869 and NGC 884 are said to be among the most beautiful objects of the night sky for binoculars and small telescopes. Both lie at distances of more than seven thousand light-years and are separated by several hundred light-years.
M 34 is an open cluster with an apparent brightness of 5.5 magnitude and lies at a distance of approximately fourteen hundred light-years. The cluster consists of about 100 stars that are scattered over an area larger than that of the full moon. Its true diameter is about fourteen light-years. M 34 can be seen with good binoculars but is best viewed using a telescope at low magnification.
The Quadrantid meteor shower is set to peak at about 11:00 p.m. on January 4. This lesser-known shower may put on a fair display. At its maximum, the shower has been known to produce as many as 250 meteors per hour, but don't expect to see that many, even in a dark sky. A more realistic number may fall between fifteen and thirty, fewer if you are observing from a city.
The shower's radiant is in the northern part of the constellation Boötes, which rises in the northeast for New Mexico at midnight. These meteors move at medium velocities (about twenty-five miles per second), are faint to very faint, and exhibit a distinct bluish color. Unlike other showers that are active for days or even weeks, the Quadrantids have a very sharp peak of activity lasting at most a few hours.
The Planets and the Moon
- Mercury makes an appearance in the early morning sky. Look just above the eastern horizon between 5:30 and 6:15 a.m.
- Venus is also up early in the dawn sky. Look between 5:45 and 6:30 a.m. low in the east. Look for a pairing of Venus and Mercury from January 5 through 11 low in the eastern sky just before dawn. Mars will be above the pair.
- Mars is rising around 4:30 a.m. in the east.
- Jupiter rises in the east about an hour after midnight early in the month to about an hour before midnight late in the month.
- Saturn is a spectacular sight, already up in the east before the sun sets and overhead at midnight. Use a small telescope to look at the rings. They are still tilted for great viewing. Titan, Saturn's largest moon, can be seen with good binoculars. NASA and the European Space Agency will send a probe into Titan’s atmosphere on January 14. Watch for some fascinating pictures of this strange, atmosphere-covered moon.
- The Moon is new on January 10 and full on January 25.
E-mail your questions or comments to Charlie Christmann at firstname.lastname@example.org.