Apr 01

April 2007

What’s Up in the Sky April, 2007

Constellation Leo

I was in the Holland Peanut Store recently talking to my good friend Paula Fabiano who delighted me with the story of her trip home from vacation. She was on an airplane flying north at sunset when she looked out the right-hand window and saw the rising moon in full eclipse. She was so excited she grabbed her camera to snap some photos. I asked her if she looked out the window on the opposite side to see the sun setting simultaneously, thus witnessing the syzygy about which I wrote last month. But, alas, the movie was just starting and the passengers on that side had pulled the shades. Apparently the pilot missed last month’s column and was not aware of what the passengers were missing.

This month one of the most famous constellations dominates the southern sky. Go out around 10:00 p.m. About two thirds of the way up from the southern horizon you should see bright Saturn and to the east (left) of Saturn is the constellation Leo, the Lion. Leo faces the viewer’s right (west). Look for a backwards question mark or sickle pattern of stars – that’s his head and mane – facing Saturn. To the left is a triangle of stars representing his hind quarters.

At the bottom of the sickle is the star Regulus, The Little King. Although many ancient civilizations had names for this star that were similar in meaning – Malikiyy, the Kingly One in Arabia, and Regia, The Star of the King in ancient Greece, for example – the modern name, Regulus, was given by Copernicus.

Leo’s image appears on coins from ancient Greece and Babylon and observations of Regulus are recorded on Babylonian tablets that date from about 2100 BC.

It is in this constellation that the point from which the famous Leonid meteors appear to radiate is located. The displays were particularly spectacular in 1833, 1866, and 1966, just after the comet that leaves the meteor-causing debris had passed by. Witnesses reported up to 150,000 meteors per hour and said they had a sensation of the earth’s motion through space.

The star Wolf 359 is located in Leo. This extremely faint red dwarf is the third nearest star and one of the least luminous stars known. Another interesting star is Algeiba, the brightest star in the curve of the sickle. It is one of the finest double stars in the sky and a good test for a small telescope.

Leo is home to a fine pair of spiral galaxies, M65 and M66, which can be seen together through a low-power telescope. M95 and M96 are another interesting pair. For more information on how to view these and other objects in Leo, consult a field guide or periodical such as Sky and Telescope or Astronomy magazines, or on the web at http://www.seds.org/Maps/Stars_en/Fig/leo.html.

This month in history:

Apr. 2: First photograph of the Sun – 1845
Apr. 7: Deployment of Compton Gamma Ray Observatory – 1991
Apr. 9: Original seven Mercury astronauts selected by NASA – 1959
Apr. 12: Yuri Gagarin becomes first human in space – 1961
Apr. 12: Columbia is first space shuttle to be launched – 1981
Apr. 16: First captured V2 rocket launched from White Sands, NM – 1946
Apr. 20: Apollo 16 lands on the Moon – 1972
Apr. 25: Deployment of Hubble Space Telescope – 1990
Apr. 28: Eugene Shoemaker born – 1928

Here are this month’s viewing highlights:

Venus shines brightly in western sky at dusk, setting more than 3 hours after sunset. Jupiter rises after midnight and dominates he southern predawn sky. Saturn just west of Leo; rings well placed for viewing with telescope.

Apr. 2: Full Moon.
Apr. 10: Last-quarter Moon.
Apr. 17: New Moon.
Apr. 19: See crescent Moon between Venus and Plieades.
Apr. 24: First quarter Moon near Saturn.

Peter Burkey – SAAA President