RSS Feeds

March Skies: History is made at Mercury

Tuesday - 3/1/2011, 12:35pm  ET

A previously unseen portion of the planet Mercury as it appeared to the MESSENGER spacecraft in 2008. (Photo courtesy, NASA)

Greg Redfern,

Ready for spring, yet? You don't have long to wait as the change in seasons astronomically occurs at 7:21 p.m. EDT March 20. I say "astronomically" because with the way our weather has been lately who knows what Mother Nature has in store for us. Notice the "EDT?" Yes, Eastern Daylight Time begins March 13 at 2 a.m.

All of this adds up to more daylight which is why we are now holding our public observing sessions at George Mason University Observatory starting 7 p.m., March 9 and 8:30 p.m. on March 23. These sessions are free and open to the public. I have been very happy to see a large number of families attending. I hope to see you there.

Skywatching Highlights

The Earth undergoes a change in seasons at the vernal equinox as spring occurs in the Northern Hemisphere and it becomes fall in the Southern Hemisphere. Day and night would be almost equal in length at this time were it not for daylight savings time. Our planet's seasons occur due to the 23.5 degree tilt in our planet's axis and our annual orbit around the Sun.

After the second week of March, Mercury will be passing near far brighter Jupiter in the western sky after sunset from March 13-16. This time will provide an excellent opportunity see the planet. Jupiter is the brightest object in that portion of the sky and is easily spotted. Once you have zeroed in on Jupiter look just to the right. The fairly bright "star" you see close to Jupiter is Mercury. Having a clear western horizon and binoculars will greatly enhance your view. I will be providing more information in my blog.

Speaking of Mercury, spaceflight and planetary exploration history will be made on March 17 when NASA and Johns Hopkins University's MESSENGER spacecraft enters orbit around Mercury. This is the first time in history that this has happened. MESSENGER stands for MErcury Surface, Space ENvironment, GEochemistry, and Ranging, which highlights the scientific goals of the mission. MESSENGER has traveled almost 5 BILLION miles and 6 and a half years to get to this milestone. I can hardly wait to explore this planet via MESSENGER and the Internet.

Brilliant Venus continues to grace the morning sky low in the southeast about 40 minutes before dawn as the month begins. On March 1 and 31 the waning crescent moon passes to the left of Venus. As the month progresses Venus will be getting lower to the horizon.

Mars cannot be seen.

Bright Jupiter is low in the west at sunset and remains visible until about two hours after sunset. The waxing crescent moon passes to the left of Jupiter on the March 6. If you have binoculars or a telescope you can watch the four main moons of Jupiter change their position night after night.

Saturn rises in the southeastern sky about two hours after sunset as March begins and at sunset by month's end. If you have a telescope be sure to check out the ringed planet.

New Moon is on the 4th, First Quarter Moon is on the 12th and this month's Full Moon occurs on the 19th. This month's Full Moon is called the "Full Worm Moon" in recognition of the beginning of spring and warmer temperatures. Last Quarter Moon is on the 26th.

Here are our down to Earth events for this month:

  • Open House at the Department of Astronomy at the University of Maryland, College Park Campus Observatory, will be 8 p.m. on the 5th and the 20th.
  • The National Capital Astronomers have their monthly meeting 7:30 p.m. on the 12th at the University of Maryland, College Park Campus Observatory. The speaker is Dr. John Debes (GSFC) on "A Stellar Debris Disk Flapping in the Interstellar Wind."
  • The Northern Virginia Astronomy Club will meet 7 p.m. on March 13 at George Mason University. The speaker is Jessica Rosenberg, "Gas and Stars in the Local Universe - What Normal Matter Can Teach us About the Formation and Evolution of Galaxies". NOVAC will host several star parties this month that are open to the public.
  • The United States Naval Observatory has Monday night tours but space is limited.
  • The National Air and Space Museum has several space related activities this month.
  • The TriState Astronomers general meeting will be held 7:30 p.m. to 9:30 p.m. March 16 at the William Brish Planetarium, Commonwealth Ave, Hagerstown, Md.

Got a Topic That Interests You? I literally have a whole universe of topics to select from for my column as I start my 7th year writing for you. But I'm interested in hearing from WTOP readers about what interests them. Feel free to contact me at with your suggestions and comments. I have also started a daily blog that you can follow.

(Copyright 2011 by WTOP. All Rights Reserved.)