Fall is in the air! Crisp days, and cool clear, low humidity nights are becoming the norm. Not to mention long nights, of course.
For now, the Summer Triangle is still high overhead after sunset, and the Lonely Star of autumn (Fomalhaut) is rising. The Milky Way is still putting on a show, for a while yet, and while Jupiter is all but gone, there’s about a month of Saturn viewing left.
Just for fun, I set up the camera for a short (15 minute) time lapse of the Milky Way straight overhead – the Summer Triangle is at the top of the frame, and Cassiopeia is rolling into frame in the lower left. Each frame is a 30-second exposure, if you’re curious.
The “event” to watch this week is in the early morning. A couple weeks ago, Mercury and Mars were in alignment, while Venus observed from the sidelines. As Venus and Mercury zip around behind the sun, though, the relative movement has been pretty dramatic. This week, Venus will approach and overtake Mars. Their closest approach will be Thursday morning (Oct 5), where they’ll be so close that you’ll need binoculars or a small telescope to pick Mars out of the glare of Venus. This is as close to a direct alignment (short of occultation or eclipse) as it gets – and of course, your eye is part of this alignment. Venus, Mars, and Earth all in a line… Syzygy!
The still shows Monday morning’s view (Oct 2) – but watch over the course of the week, and it will be clear that these are planets! I’ve embedded a short movie here stitching together screenshots from Stellarium. Each day shows the eastern horizon at 6:30am for 8 consecutive days, beginning on Monday, Oct. 2.
Monday morning has a bonus from the Mid-Atlantic. If you’ve got a fairly low view of the southern and eastern horizons, look toward Orion and Canis Major in the pre-dawn south. The Hubble Space Telescope will be tracking south-to-east on Monday morning, tracking towards the planets. At about 6:28, the HST will be just below the triangle that makes up Canis Major’s back leg, and directly below Sirius. Movement will be obvious if you can see low enough in the sky to pick it out.
Get Out There!