March 2012

March Good Month for Planet Gazers


For star watchers darkness still descends in the early evening hours at this time of year. This means there is still plenty of time for observing the clear night skies in relative comfort before bedtime. So far this winter we have been blessed with several clear nights of above average temperatures. Normally this time of year I spend very short periods of time under the stars with binoculars. This year the moderate temperatures after sunset have made it a pleasure to be outside a bit longer with my telescope.

This year March will be a good time for observers to see the brighter planets.

The planet Mercury can be spotted only during the first week of March low above the western horizon a half hour after sunset. It can be easily seen about 30 degrees below and to the right of brilliant Venus.

Venus is easily identified by its brightness and pure white radiance shortly after the sun goes down. Many people have looked at Venus and mistaken it for an aircraft’s landing light. Its exceptional brilliance (magnitude -4.4) is due to sunlight reflecting off its white cloud tops as well as Venus catching up to Earth in its orbit. A telescope will show Venus in a “quarter phase”. The planets of Mercury and Venus go through phases similar to those of the moon as seen from Earth.

At the beginning of March Jupiter lies 11 degrees above and to the left of Venus. The yellow colour of the Giant Planet makes it easy to identify. Even though it is fairly bright at magnitude -2.1 it is still just over six times fainter than Venus. Throughout March Venus catches up to Jupiter until March 12 when they are a mere three degrees apart.

Mars rises in the east just after sunset at the beginning of March. Moving retrograde (westward) amongst the stars of Leo its motion is easily noticed even night to night against the background of stars. The Red Planet comes to opposition on March 3 and is closest to Earth two days later. It is at its brightest (magnitude -1.2) just a little fainter than the white star Sirius in Canis Major. Sirius is the brightest star in the night sky. Since Mars is at aphelion (farthest from the sun) this opposition will not provide us with views as good as the opposition of August 2003.

Saturn rises around 11:00 p.m. at the beginning of March in the constellation of Virgo. The rings are always an attraction for all observers. At this time they are tilted 15 degrees to our line of sight. The dark gap (Cassini’s Division) is visible in a telescope near the rings’ outer edge.

On the night of March 6 the waxing gibbous moon is near the star Regulus. The next night the moon has moved to a point just below Mars. At nightfall on March 25 the waxing crescent moon can be seen very close to the upper right of Jupiter. The next night the moon will be to the left of Venus. This grouping provides a rare opportunity for a good photo.

The Thunder Bay Centre of the Royal Astronomical Society of Canada extends an invitation to all interested observers to attend our first public observing session of 2012. It will be held at Hillcrest Park on Friday, March 2 beginning around 8:00 p.m. EST (Eastern Standard Time) until 11:00 p.m. EST. Centre members will have binoculars and telescopes available to observe the planets Venus, Jupiter, Mars as well as the Moon and other celestial objects. If the skies are cloudy the event will be held the next evening (March 3). Dress warm and bring your astronomy questions for our group.

Daylight savings time starts on Sunday, March 11 so remember to turn your clocks forward one hour before retiring to bed on Saturday night.

The March, or vernal, equinox occurs at 1:14 a.m. EDT (Eastern Daylight Time) on March 20. This denotes the first day of spring for us in the northern hemisphere. For those living south of the equator in the southern hemisphere the summer season ends and autumn commences.

To aid the budding observer in their quest to explore the universe I will be offering the “Backyard Astronomy – Stargazing for Everyone” course at Confederation College commencing March 29. This course is geared for those who are starting out in the hobby of amateur astronomy and want to learn more about the night sky. We also discuss how cameras, binoculars and telescopes work as well as what equipment will be best for our interests.  For more information contact Confederation College.

The Thunder Bay Centre of the Royal Astronomical Society of Canada (RASC) holds general meetings at the Dorion Building at Confederation College. They are held on the second Tuesday of each month (except July and August) at 7:00 p.m. (room number displayed on TV monitor just inside the building). Interested non-members are always welcome to our meetings.

Clear Skies

Ted Bronson