April 2001 Sky from Keeble Observatory

Mir is down, apparently safely. The 140 ton, 15 year old space station was dropped into the atmosphere early on March 23rd. Most of it vaporized from the heat of reentry, but several large pieces, totaling about 25 tons, splashed into the Pacific Ocean, far from any land. Observers in Fiji could follow a series of fireballs flaming across the sky, followed by four loud sonic booms. Russian controllers brought the station down rather than risk losing control, which might result in having it reenter over a populated area. Although they are experienced at these maneuvers (its essentially the way they had disposed of their trash for the last 15 years!), there was sufficient anxiety about bringing in the largest single object ever returned from orbit that the Russian government purchased a $200 million insurance policy "just in case."

A tantalizing light spot, actually just two or three pixels in the image plane of the Mars Global Surveyor satellite, may be the first sighting of the doomed Mars Polar Lander, launched in January of 1999, and lost 11 months later. Experts at the Department of Defense's National Imagery and Mapping Agency - a.k.a. NIMA, the same folks who analyze spy satellite data - have been examining orbital imagery of the intended landing site for clues concerning Polar Lander's demise. In a single image, at approximately the right location, they identified three light pixels against an otherwise dark background.

If confirmed by finding the same spot in different images, it would be the first direct evidence that the $165 million probe actually reached the surface of Mars. A NASA inquiry panel concluded that a software fault shut down the descent rockets prematurely, causing the craft to drop the last 130 feet of its programmed descent and crash into the surface.

Lunar phases for the month: All times here are EDT. First Quarter on the 1st, at 6:49 am, and again on the 30th at 1:08 pm; Full Moon on the 7th, at 11:22 pm; Last Quarter on the 15th (Easter Sunday), at 11:31 am; New Moon on the 23rd, at 11:26 am.

Planet observing will be a bit sparse in the evenings. Jupiter and Saturn are to the west at sunset, and will be lower in the sky as the month progresses. They'll disappear into the Sun's glare by the end of May. Mars rises just before midnight at mid-month, so it's best suited for early morning viewing. Don't confuse the "Red Planet" with its stellar rival, Antares. They're in the same general direction, with Antares a bit above and to the right. Venus, which dominated our evening skies last month, is now making its appearance in the pre-dawn twilight. It will rise earlier as April progresses. Binoculars or a small telescope will allow you to see it as a thin crescent.

Our 9:00 pm overhead view at midmonth finds a nearly-empty patch of sky at zenith. We bid farewell to Orion to the southwest, setting earlier each evening. It's at about the same height above the horizon as Jupiter and Saturn. A bit further to the southwest is the bright star Sirius, in Canis Major - also disappearing from our view until late next fall. Above Orion we see the bright pair, Castor and Pollux, in Gemini. These contellations lie in a rich starfield near the plane of the Milky Way. Our overhead view looks away from the plane of the Galaxy, which explains the relative dearth of stars. About the same distance from zenith as Castor and Pollux, but a bit east of due south, we see the familiar "sickle" of Leo, dominated by the bright Regulus, which marks the heart of the Lion. Arcturus, the brightest star in Bootes (the Herdsman) rises due east. At 9:00 it is about 30 degrees above the horizon. To the southeast, and a bit lower is Spica, the brightest star in Virgo. High above the northern horizon, the "Big Dipper" of Ursa Major is inverted above the pole star, Polaris.

The sky has its own rhythms, known for many centuries and the basis of our calendars. A year ago, the descriptions of the constellations would have been virtually the same. The planets, however, wander against the background stars - last year's description would not match. Indeed, the name "planet" comes from a Greek word which means "wanderer."