Spring 2013 Observing Highlights
Snakeheads, Crab Cakes and PANSTARRS… Goodbye Jupiter. Hello Saturn, Vesta is fading fast.
by Stan Howard, ACA VP Observing
So you think the cold winter weather makes the snakes go underground? Maybe all the small ones (those less than a zillion miles long) do, but the really BIG ones come out every night then. Each night during the spring, the longest snake of all, Hydra, raises its nine ugly heads from the horizon in the East and slithers along on its East to West path during the night. After Hercules and Iolus cleverly killed it a long time ago, Hera is said to have put it in the heavens, along with its accomplice, Cancer the Crab. The story generally goes that the second of Hercules’ twelve tasks was to GO DO the Hydra that Hera had specially arranged for Hercules’ demise. Anyone knows that the best way to DO a snake is to chop off its head, but Hercules had a real problem there. It seems that Hydra had nine pretty nasty heads, each of which would grow back into two heads if they were cut off. One of the heads was even immortal. To make matters worse, the Hydra had such bad breath, that the stench from each mouth (being part of a nine pack as it were) could kill a person. You may have experienced a similar problem before in a crowded elevator. Hercules invented the first gas mask by placing a cloth over his mouth and nose (the concept later evolved into an industrial grade particle filter) to stop the stench. Luckily, Hercules had a quick thinking assistant in Iolus (in real Mythology life, not TV Land). Iolus suggested that the best way to keep a head wound from growing back would be to cauterize with fire any cuts to short circuit that head sprouting thing. So Iolus carried a torch to seal the problem as soon as Ol’ Herc lopped off each head. This action did double duty, since the blood of the Hydra was also poisonous. When Hercules got to the last (and Immortal) head, he lopped it off and bagged it up for safe burial later under a big rock. This is why sometimes even now you get nasty surprises if you look under big rocks. You can see the nine head stars of Hydra clustered together as one head of Hydra. Five of them outline the head of Hydra, but they only appear to be together. The following are names, brightness, and distances of the nine head stars as I reckon them: Epsilon Hya @ 3.40 mag, 135 ly; Delta Hya @ 4.10 mag, 179 ly; Sigma Hya @ 4.45 mag. 352 ly; Eta Hya @ 4.30 mag. 466 ly; Rho Hya @ 4.35 mag. 332 ly; Hya 10 @ 6.10 mag. 207 ly; Hip 42899 @ 6.85 mag. 399 ly; Hip 42891 @ 6.45 mag. 414 ly; Hip 42854 @ 6.35 mag. 738 ly.
So what about the Crab? When Hera saw that Hercules and Iolus were keeping their wits about them, and the Hydra was not keeping its heads about it, she threw in Cancer the Crab to somehow turn the tide of the battle by distracting them. Hercules must have thought the crab was a big spider and was not impressed. He simply did what most people would do if they saw a big spider: he squashed Cancer into a flat crab cake with his boot. The whole incident is immortalized in the night sky for you to see this Spring.
Speaking of Crabs, if you want to get a jump start on finding Messier Objects before the BIG Messier Marathon this spring, you might as well start checking some of them out. Why not start at the start by seeing if you can identify M1, the Crab Nebula? It is right next to the easternmost horn tip of Taurus. Other M’s to get familiar with this spring could be M36, M37 and M38 in or near Auriga. I refer to my copy of Stellarium for help in locating all (not manmade) sky objects.
February will have the last call for two favorites of the night sky. The Andromeda Galaxy will be getting lower in the West each night until it will be setting around 9:00 PM by the end of the month. I always miss it during the months of the year when Andromeda is not easy to show to people. You’d also do well to get a last glimpse of Jupiter before the start of May because Jupiter will be setting after about 9:00PM by then, though it will be a brighter -1.54 by then.
However, the schedule for sky entertainment is seldom thin, and another of the gas giants, Saturn will be rising earlier each night this spring. About the 1st of March, Saturn will rise about midnight with a brightness of magnitude 0.61. By May 1st, it will be rising about 9:00PM with a magnitude of 0.35. Saturn is a "don't miss spectacle" through any telescope. Through a larger scope, you can also sometimes see about five of its moons.
Coming in March to a hemisphere near you will be Comet PANSTARRS, fresh and (hopefully) glowing from its trip around the Sun. It (may) be the first of the (BIG?) comets of 2013. So far, predictions are that it will be a naked eye visible comet with a fairly wide tail when viewed through binoculars or telescope. Depending on how its gases boil away, it may stay visible for about a month as it heads north and back to the 'cloud'. It may serve to whet our appetites for Comet ISON in November.
Remember Venus? It will not be visible until it moves away from the Sun (from our vantage point) in June. It will be a fairly bright -3.34 by then.
Mercury? Usually visible for only days at a time only a few times a year, on about June 8-10, Mercury will be about 24 degrees up from the setting sun, just viewable at NMR-DSO for a few minutes right at dusk. It is always a treat to catch a glimpse of Mercury in the glow of the evening sky where few stars dare to make themselves seen.
Since the DAWN spacecraft left Vesta and is heading to Ceres, no one pays much attention to Vesta's fading image. Vesta is fun to watch from night to night as it moves through the heavens noticeably like other asteroids which are normally hard to see. If you want to follow Vesta before it leaves the horns of Taurus near Jupiter, it is presently a findable magnitude of 7.16, but by May 1, it will just be only 7.76 mag. ~35 degrees above the Sun just after dark near the bent foot of Castor. I always refer to a laptop comparison of star backdrop patterns from Stellarium to ascertain which of the points of light in my binocular field of view is actually Vesta. It is good practice at star hopping to follow Vesta for several night in a row.
Uranus (6.27mag)... last call for viewing it in the evening low in the west will be about March 1st. Uranus (then 6.26 mag) and Neptune (7.75 mag) will become early morning risers in May.
There are plenty of interesting things to see out there. Just watch out for the snakes, crabs, flying PANSTARRS and hurtling asteroids. Since their close call Valentine's surprise from above, I know the Russians in Chelyabinsk will be looking up.
ACA VP Observing