August 2014

Greetings Lookout Observers,

There is currently a comet in your night sky that, though too faint to be seen with the naked eye, is visible as a little blob of light with a good pair of binoculars held steady. It is Comet Jacques (2014E2), named, as all comets are, after its discoverer. Because it is in the constellation of Cepheus, headed toward the constellation Cygnus, it is well placed for Northern Hemisphere observers, being somewhat North of straight overhead just after dark. In another week or two it will probably start fading from view. Last week at Lookout Observatory I observed the comet in binoculars and then photographed it with the 11-inch diameter telescope for a close up view. Comet’s tails are what usually makes them interesting, but I couldn’t see any tail in the binoculars, probably because the comet had already moved too far from the sun. The Manx is a kind of cat that doesn’t have a tail, so I thought it might be appropriate to call this comet a “Manx” comet. The first picture attached is a photo of Comet Jacques, but all that can be seen is it’s greenish head even though this is a 30 minute exposure (60 thirty second exposures stacked). The nearby stars are all streaked because I tracked on the comet, and it moved that much in 30 minutes. (To give you a sense of scale, the full moon would fill up this whole photo.) If there is any tail at all, it is very short and extends to the lower right of the head

Because a tailless comet is not so interesting, I am also including a second photo which I took the same night as the comet picture. It is of NGC 6781, a small planetary nebula in the constellation Aquila. Planetary nebulae get their name because when they were first being discovered, they looked like a planet looks in a small telescope. In reality they are many light years away, scattered across our Milky Way Galaxy. They result when many stars, as part of their evolution, blow off a massive shell of gas which then expands, usually in a sphere. It usually looks like a ring because the gas is dense at the sides where you are looking through lots of it, and thinner in the middle where you are looking straight through the spherical shell, and therefore there is less gas. This nebula is about 2 light years across (about 30,000 times the diameter of the Earth’s orbit around the sun), but because it is so far away (a couple of thousand light years), it looks very small in a telescope. This photo covers the same amount of sky that the comet photo does, so you can see it appears smaller than the comet. Please enlarge it to an inch or two across so you can see the full color beauty of it. When the image is blown up, you can see the small blue star in the very center that originally blew off the nebula. All the other stars are foreground or background stars. The blue in the nebula is caused by reflection of light from the blue central star, whereas the red in the nebula is caused by the emission of light from hydrogen gas that is energized by the radiation from the central star.

I hope you enjoy these celestial wonders and have had an enjoyable summer. And remember …

Keep looking up,

Carter,

Sometime Resident Amateur Astronomer,

Lookout Observatory