Celebrate National Dark Sky Week and Astronomy Day. April also brings the Lyrid meteor shower, Saturn's rings at its widest for the year, and the reappearance of Mercury.
National Dark Sky Week March 29 to April 4
With everyone working together, April will leave you in the dark this month. The fight against light pollution is highlighted (or is it lowlighted?) by the sixth annual National Dark Sky Week March 29 to April 4. The World Wildlife Fund has instituted an Earth Hour for March 29, encouraging people to power down their homes, businesses, and recognize the impact they have on global warming. Part of this impact is the unnecessary burning of lights.
While doctors and psychiatrists can talk about the physical and mental health benefits of darkness, an astronomer can show you by taking you outside and having you look up. Over history, humans have had a real connection to the night sky as it was always present, just beyond the circle of the campfire. Now there are people who have never seen a truly dark, starry sky.
Make an effort not only at the beginning of April but from now on to turn off excess lights. Install motion lights that only turn on when they are needed. And step outside in the dark and reacquaint yourself with the night sky.
Astronomy Day Is April 21
Astronomy Day comes the day before Earth Day, April 22. Overnight from April 21 to April 22 you can watch the peak of the Lyrid meteor shower as a way to celebrate one of the best sky shows on Earth. The Lyrids are one of the better showers of the year, however, this year the show will be cut short by the rising of a nearly full moon a couple hours after sunset.
The constellation Lyra, from which the meteors appear to emanate, rises in the northeast a little after sunset. A comet named Thatcher left behind the debris that lights the sky in April, producing a zenithal hourly rate of approximately 12 meteors.
Tracking the Moon in April
New Moon occurs on April 5 at 11:55 pm EDT. Because the full moon in early April falls on a Saturday this year, it makes for perfect timing for anyone wishing to partake in a Messier marathon. A Messier marathon is when observers try to observe as many of the Messier objects as they can in one evening. A dark sky is a must and spring provides the best time to catch all the possible Messier objects.
On March 8, the moon lies near the Pleiades and occults some of the stars for those in the north and east portions of the US and Canada. A few days later, on April 11, the moon pairs up with Mars, which is a reddish 1st magnitude light.
The full moon occurs at 6:25 am EDT. Look for the Lyrid meteors the next couple nights after sun has set but before the moon rises.
Seeing Saturn and Mercury
Saturn's rings are becoming harder to see as the planet tilts them to point right at us and practically disappear from view in 2009. On April 28, Saturn's rings will be 9.94 degrees from edge-on, showing their maximum extent for the year. Not until 2010 will they appear as wide again in Earthly telescopes. Saturn is in the constellation Leo close to the bright star Regulus.
Mercury begins its best apparition of the year at the end of April and will continue to be a good target through most of May. The last couple days of April, Mercury will appear above the horizon after sunset, shining at a bright magnitude -1. It will lie close to the Pleiades star cluster, which it will pass in early May as it comes in close quarters with the moon.
