Pete's Stuff

Southern Stars

On Wednesday night, the sky above Moloka‘i cleared out, and I took some pictures from the lānai.

Sagittarius setting in the southwest, with the Great Star Cloud, the Lagoon Nebula (M8). Corona Australis is on the left.

The center of the galaxy.


Bits and Pieces

I haven't posted for a while because I've was too busy relaxing at the cabin, then the North Shore. Still a few notable things, though.

Monday through Wednesday at Savanna Lake we had beautiful clear skies. Tom had brought the 8-inch Newtonian and I used it to spot a bunch of objects I'd never identified before (due to lack of a sufficient 'scope) - M57 (the Ring Nebula), M101, M27 (the Dumbbell Nebula), M15, M2, Uranus, Neptune, M11, and even the Helix Nebula low on the horizon - faint, but unmistakable. We were also able to see the dusty speckling of the brightest individual stars in M13 - an exciting addition to the usual "fuzz spot" sighting. The field-glass objects like M8, M31, M33, and the Perseus Double Cluster were spectacular. One of the things that really made things easier was Tom's green pen laser - after a short consultation of the start charts and a look through the 10x80s to fix the starfield in memory, I was able to lay the laser against the barrel of the 'scope and position it to within a fraction of a degree of even very faint objects, in most cases within the FOV of the 25mm (48x) eyepiece.

One thought that struck me during one of those nights is that a sky map is, you know, a map. And my memory for maps seemed to apply, whether it's on the earth or beyond.

It rained all day Wednesday and Thursday, though. On Friday, we packed up and headed for Grand Marais. It had cleared up again, and on Friday night I went out to Artist's Point after midnight with the tripod and camera. I gathered a bunch of time exposures at ISO 800, but none were enough to turn into photos, even when stacked. The signal-to-noise ratio was just too low. Individual bright stars weren't a problem, but I wanted to get the Milky Way as it descended into the horizon over Lake Superior, and there wasn't enough distinction between the Sagittarius star cloud (M24) and sensor noise. One interesting point is that I managed to capture orange light from not one, but two towns on the other side of the lake that was utterly invisible to the human eye. Unfortunately, it only confounded the image further. I'm guessing the layer of humidity lying over the lake probably contributed to the scattering that caused these horizon effects.

So after a nice relaxing time, I'm leaving again at the end of the week for Laramie Daze. I'll be posting about the courses, both here and on Attackpoint, and without a portable scanner I'll have to make do with photos of the course maps. That should do. Then, on to Colorado!

However Far Away

I'm a couple days late on this one, but that's OK. Those of you with some interest in astronomy have no doubt heard about the recent launch of the Kepler spacecraft, which was designed to systemically detect and catalog the variety of extrasolar planetary systems. The launch went well; "first light" was a success, and as a bit of a warmup exercise, Kepler then gathered its first real science data by measuring the light curve of an already-known exoplanetary system called HAT-P-7. And what a measurement is was! On August 6th, the Kepler team called a press conference to announce the results:

Source: Kepler Mission

It's amazing how much detail this shows, considering that HAT-P-7 is around 1,000 light years away.


Neat Stuff on the Intertubes: Ka-Boom!

So what the heck is this, caught on video one night in August 2007? Hint: it's not a evening fireworks display.

Click on the still frame to play.

Click through and play the video to find out. (NB: I have lost the original source for the video and would love to give credit to the author, if I could! Unfortunately there is no name mentioned in the video.)


Baby, You're a Star! Part II

To continue my previous post, these are a few more interesting celestial "characters".


Baby, You're a Star! Part I

The next time you go outside at night, and it's clear with no moon out, look up. Did you know that each of those little stars you see has a personality? And I'm not talking about that joke calling themselves the "International Star Registry". Most of them look the same at first, but as you look harder you can tell some differences. First off, and most obviously, some are brighter than others. Looking more closely, there's subtle differences in color - some look white, others are bluish, some are yellowish, and some are reddish.

Astronomers go to a much higher level of detail by taking detailed spectra of stars - and even amateurs can do this with a small telescope and inexpensive equipment - and from those spectra they can deduce a number of things about individual stars. Tongue in cheek, here's a few of the more interesting "characters" in the sky above you.