I truly need to catch up on sleep. I’ve been up until 2 or later the past couple nights. For good reason. Last night I attended the Furtman Farm Star Party in northern Wisconsin, an annual gathering of starry-eyed men and women who will stop at nothing – neither frost, nor dew nor the sweet whispers of sleep – to track down comets, star clusters and the finest details of Jupiter’s cloud belts at all hours of night. We were fortunate to have clear skies and steady seeing as well one fellow who could bark like a coyote. Between hunting carbon stars and globular star clusters, he barked a lone coyote almost to within petting distance. OK, I exaggerate, but just a little.
After we’d had our fill of the celestial vault, we took a break to “laser paint” a big, old grain silo on the property in what’s becoming an annual tradition. After a half dozen free-form portraits based loosely on Christmas trees, fires, stars and joists of light, we were suddenly hungry. Under the dim red light our happy host Greg Furtman installed in his kitchen, our group enjoyed all kinds of snack food including so-called “Five Alarm” hot peanuts. After much sampling and debate we agreed they were closer to 2.5 alarms.
Our group returned to the dewy cold and peered at the fantastic spots and belts of Jupiter until 1:30 a.m. I drove home fortified by the pleasures of laughter, conversation and friendship shared with one of the finest groups of people on the planet … on any planet.
Tomorrow Comet Elenin will pass closest to the sun in the sky as seen from Earth. Don’t get too excited, because there will be nothing to see. First, let’s dispel the baloney about the comet blocking the sun. It’s not only much, much too small to accomplish this, but we’re not even sure there’s a comet there anymore. Elenin started falling to pieces in late August and by the time of last telescopic observation some 11 days ago, it had faded to below 10th magnitude – dim! More importantly, Comet Elenin will NOT pass in front of the sun, because its orbit takes it some 2.2 degrees or four full moon diameters above the sun. That’s a complete miss!
When a planet or comet or other celestial object lines up closest to the sun on a north-south line, we say the two bodies are in conjunction. Conjunctions are very common, happening all the time during every year. Saturn was in conjunction with the sun this summer and Mercury will be on September 28. Not a big deal – just the mechanics of planets orbiting about the sun in roughly the same flat plane called the ecliptic. Some are closer to us like Mercury and Venus; others like Saturn are farther away, but they regularly bunch up and appear close to one another when they appear in the same line of sight.
Mercury, Comet Elenin, the sun and the moon all lie at very different distances but appear along the the same line of sight Monday.
On September 26 about 11 p.m. Central time, Comet Elenin will be in conjunction with the sun. Since comet and sun are continually moving, a conjunction lasts only a moment, though in terms of proximity, they’ll be near one another for a few days. After conjunction, the comet moves west of the sun and will appear in the morning sky. Keep your fingers crossed something’s left to see.
Many had hoped Comet Elenin would show up in images taken with the Solar and Heliospheric Observatory’s (SOHO) C3 coronagraph, a device with blocks the glare of the sun to show the nearby solar environment. Nope, not there. See for yourself in the picture I grabbed today. That means the comet is certainly below the SOHO magnitude limit of 7 and undoubtedly MUCH fainter. Some amateur astronomers had hoped that backlighting of Comet Elenin’s dust would cause a re-brightening as it approached the sun the same way your breath lights up on a winter day. If that’s happening, it’s still too dim for SOHO to see.
The comet is completely invisible down here on Earth because of glare from sunlight now through the end of the month. By about the 10th of October, it may be visible through large telescopes in a dark sky in Leo the Lion shortly before the start of morning twilight. I’ll put together a map soon on how to find it for those who like a challenge. Meanwhile, what’s left of the comet might still show – though I doubt it – in SOHO images through September 29.