Almanac for March 2013 by Bob Kelly, from the Westchester Amateur Astronomers’ Newsletter
Let’s start with what we can’t see this month! Mercury, Venus, Mars, Uranus are hiding behind the Sun in March (or we are hiding from them!). That leaves us with Jupiter, Saturn and thousands of stars and deep sky objects available to the observer with any optical aid. Oh, did I mention comets? See the separate article in the newsletter:
http://www.westchesterastronomers.org/ Scroll down and click on March 2013.
Jupiter and some attendant star clusters make a great target for astro-photographers of any level of experience. Use a tripod or something to hold your camera – any camera – steady. If you can change the exposure settings, use a low f number setting and the longest time exposure you can take (up to 20 or 30 seconds) with the maximum sensitivity. (If the maximum sensitivity, or ISO setting, makes a photo that has lots more dots than there are stars, try a less sensitive setting to reduce background noise.) Also try getting the scene with Jupiter and the Moon nearby on the 16th or 17th. Send the results of any attempts to our WAA facebook page! If you get a nice photo, suitable for framing, print it at a photo store or web site, even an instant photo place. If you print on a home printer, you’ll use up tons of black ink from your print cartridges.
The Moon will pose for pretty photos with Jupiter in April and May, as well. As Jupiter gets lower in the evening sky each month, the Moon will be thinner as it passes Jupiter’s neighborhood. With a less bright Moon, it will be easier to pick out the nearby star clusters, until Jupiter starts to set before the end of twilight, starting in mid-May.
Often, we can see the planets passing through the field of view of the SOHO solar observing satellite’s C3 camera. Watch for Venus later this month and if you see a much dimmer object moving slightly differently from the surrounding stars, it may be Uranus.
Saturn teases us this month. By the 9th, Saturn is rising by 10:00pm, just barely above the horizon during the last hour of prime time TV. But on the 10th, Saturn’s rising time backs up to 11pm, making the pre-dawn hours the best time to seek the ringed planet and its moons. This is thanks to our change to daylight time on the 10th, so I guess Saturn isn’t to blame. Saturn-rise continues to move to earlier, by 9:30pm at the end of March. When I observe Saturn, I first look at the rings, then find Titan, its brightest moon, then look for faint butterscotch bands on the planet and then pick out its fainter moons. How many of Saturn’s moons can you see? Titan is visible in most telescopes. The rings are open wider than last year, now 19 degrees, and their brightness makes it harder to see the other moons. The next moons, going inward from Titan, are Rhea, Dione, Tethys and Enceladus. Each is fainter than the other, as well as closer to the planet, making them doubly hard to see.
Then we have my favorite Saturnian moon, Iapetus. Iapetus is further out from Saturn than the other bright moons. It is two-faced, bright on one side and dark on the other. It shows its brighter side this month, when it is traveling ahead of Saturn, that is, to Saturn’s west in our sky. Iapetus gets as much as three times farther away from Saturn than Titan. By the end of the month, Iapaetus is dimmer, and just north of Saturn, on its way to being dimmer than Enceladus in late April when we get closest to Saturn for the year and Iapaetus is following Saturn in the sky. Our Moon joins the Saturn scene on the 2nd and the 29th.
The Sun appears to pass through the celestial equator, sparking out celebration of the equinox (spring equinox for us Northern Hemisphereians) at 7:02am on March 20th.
Mercury struggles to gain altitude in the morning sky, getting farthest from the Sun on the 31th. While the change to daylight time moves sunrise to after 7am, a more accessible time for viewing the morning stars, Mercury never gets high enough in the sky to be seen without optical aid. But Saturn will still be up then to keep you company.
International Space Station sightings are available to us in the morning sky from the 12th through the rest of the month. If you’d like some music from the ISS to accompany your observation of the ISS, there’s always Chris Hadfield and Ed Robertson: http://music.cbc.ca/#/concerts/Chris-Hadfield-and-Barenaked-Ladies-ISS-Is-Somebody-Singing-2013-02-05
That’s all for March!