Archive for March, 2010

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DIY pictures from the edge of space

March 26, 2010

This photo was not taken by NASA or the European Space Agency or the Air Force, or by any organization at all. It was taken by Robert Harrison, a 38-year-old IT director from Yorkshire, who put a garden variety point-n-shoot digital camera on a helium balloon. According to Sky News, his rig cost about 500 quid, or just under $750. Harrison programmed a little gizmo that makes the digital camera take photos or videos at set intervals. The big load of goodies is at his Flickr site. Be sure to check out the Icarus 1 videos, they are mesmerizing.

The balloon carries the camera up to 22 miles above the Earth, at which point the pod carrying the camera detaches from the balloon and parachutes back to the ground. Harrison uses a GPS locator to recover the camera.

Twenty-two miles is 116,000 feet, or 35 km, still well within the stratosphere. That’s much higher than commercial airliners fly (around 40,000 feet), and in fact only a handful of manned aircraft are capable of flying over 100,000 feet. At that altitude the sky is black and the curvature of the Earth is obvious, so it is informally known as the “edge of space”. Space itself is quite a bit farther up. In the US, the definition of an astronaut is someone who has been at least 50 miles up (264,000 feet, 80 km). By comparison, on its final flight SpaceShipOne reached an altitude of 69 miles (112 km), and low Earth orbit starts at about 100 miles up (160 km). I bring that up just to establish context, not to detract at all from Harrison’s achievement. Getting pictures back from altitudes higher than those reached by the SR-71 Blackbird (~85,000 feet) on a budget of less than a thousand bucks is flat-out amazing.

I wonder who will be the first to duplicate his feat?

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Binocular Messier bling

March 24, 2010

More bling in the mail today: my certificate and pin for the AL Binocular Messier Club. The pin is already on my Kepler cap, which is now triply geeky (once for this pin, once for the Lunar Club pin, and, let’s face it, once for being a ballcap that celebrates a space probe).

If you are a member of the Astronomical League–and if you’re a member of a US astronomy club, AL membership is probably included with your local club membership–this is a no-brainer. You only have to see 50 Messiers with binoculars to complete the Binocular Messier Club requirements and score your own bling. I’ve gotten 99 Messiers with binoculars so far, not because I have to, but because it’s fun. And because the more I see with modest instruments, the less I feel like a wuss next to Jay Reynolds Freeman.

But mostly because it’s fun. After looking at small patches of sky at medium or high magnifications, it’s nice to sweep large swathes of the sky at low magnification. I’ve learned more about the forms of celestial objects at the telescope–but I’ve learned more of my way around the sky with binoculars. It’s the perfect project for a beginning stargazer, whether you’re in the Astro League or not. Give it a shot!

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The Moon and Pleiades, again

March 24, 2010

I wasn’t happy with the photo/sketch of the Moon passing the Pleiades that I showed in the last post. The field of view was too cramped to match what I saw at the eyepiece, and I put the stars in by flipping back and forth between Stellarium and GIMP and eyeballing things.

So this time I did it right: got a screenshot from Stellarium, pasted it into a layer in GIMP, placed the stars in a separate layer on top of that, and then got rid of the screenshot layer. Here’s the result, which is very close to what I actually saw Saturday night:

I liked the new version so much that I made a full-screen version. I don’t have any eyepieces that can actually show this much sky at once, but it looks pretty and I don’t care. Here it is:


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Observing Report: A New High

March 21, 2010

Last night I was back down at the Salton Sea. I got down there right at sunset, found a spot in the Mecca Beach campground, and got the scope set up a little after 7:00. The sites on either side of me were empty but I had neighbors farther down the way and across the road that runs through the middle of camp. I walked around and invited people to come see the moon.

About eight people drifted in over the next hour or so, and most stayed for quite a while. We looked at the waxing crescent moon, Venus, Mars, the Great Nebula in Orion (M42), the Beehive (M44), M41 in Canis Major, and Mizar and Alcor. Saturn got up out of the near-horizon murk so we got a good look at the ringed planet and four of its moons. Mars showed a polar cap, some dark surface detail, and a possible cloud near the equator. Eventually we went on to galaxies–M81 and M82 in Ursa Major, which looked awesome in the same field of view, M55 and M56 in Leo (ditto), M51 and its satellite, and, most memorably for me, the Sombrero Galaxy (M104). The dark lane of dust that runs across the Sombrero was easy to see, and under those dark skies the galaxy showed a surprisingly extensive halo extending above and below the plane of the disc.

I’ve started working on the AL Caldwell Club so I spent some quality time on a couple of planetary nebulae, the Eskimo or Clown Face Nebula (NGC 2392) and the Ghost of Jupiter (NGC 3242). The Eskimo showed its prominent central star or ‘nose’, and in averted vision I could see some detail in the gaseous halo, but it was small and short on detail compared to the Ghost of Jupiter. The latter nebula was just awesome–it seemed about twice the diameter of the Eskimo, and there were definitely at least two concentric shells of gas around the central star, with the inner shell being brighter than the outer and clearly elongated out of round. Look at this image from about ten feet away and you’ll have a pretty good idea of what it looked like in the eyepiece.

I got a good look at Omega Centauri, the immense globular cluster that just gets over the southern horizon here. It was suffering from being down in the dense atmosphere near the horizon, but it was still a big ole ball of stars. At 92x, it looked as big or bigger in the eyepiece than M13, the Great Glob in Hercules, looked at 184x, and its stars looked smaller and more numerous. It is truly an outstanding object.

And speaking of M13, it was pretty darn good once  it got a good way up the eastern sky, with lots of resolution and long chains of stars emanating from the central ball.

It was  great night. As much fun as I had during the Messier Marathon last month, I had more fun last night just surfing around the sky and showing people cool stuff. I got better views of planetary nebulae, globular clusters, and galaxies than I have ever had from my own scopes. But the most amazing thing I saw all evening was, believe it or not, the moon.

I set up the telescope right before dark, tweaked the mirror alignment, and got the scope on the moon just by dead reckoning, without using the finder. The moon was exceedingly detailed and the entire globe stood out very clearly against the sky, which was not yet fully dark. And the moon was surrounded by stars, which was weird. Admittedly, it was still just a crescent moon, but between the glare from the moon and the evening twilight I didn’t expect to see any stars at all in the same field. They were there,  though. It occurred to me that the moon might be passing in front of a star cluster, as happens from time to time. Finally I got around to checking the finder scope and saw that the moon was cruising right past the Pleiades.

The view in a low-magnification eyepiece was indescribably beautiful, but I’ll try to describe it anyway. With the sky not fully dark, the razor-sharp moon seemed to hang suspended in front of a dark velvet blue sky, with the stars shining out like a halo of fireflies. The impression of depth was overwhelming–I could almost reach through the telescope and pluck the visibly spherical moon from among the streams of stars. Intellectually, I know the distances are all wrong–the velvety blue sky was in front of the moon, not behind it, and the stars were incomprehensibly more distant–but that’s what it felt like.

I took my best photo from last night and mocked up a very crude representation of what this looked like at the eyepiece. Imagine trying to tell someone about Michelangelo’s David when all you have to show them is a doodled stick figure and you’ll have a sense of what I’m up against. Nevertheless, here goes (image processing in GIMP, star positions from Stellarium):

UPDATE: I made a much improved, more realistic version of this image and put it in the next post.

So, I have a new favorite sport: catching the moon in front of star clusters during twilight. I’m sure it won’t happen that often, but the memory of just this first catch will last a lifetime. It was, hands down, the most incredible thing I have seen in any telescope of any size, anywhere, ever.

Best of all, it was accessible–anyone pointing even the most modest telescope skyward at the same time last night would have seen the same thing. So stay alert, you never know when the most seemingly ordinary of celestial objects will jump up and blow your mind.

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Concordiem Australis

March 16, 2010

One of the nice things about living in smoggy, light-polluted LA county is that traveling almost anywhere means access to darker skies. Just in the past year I’ve gotten to observe under dark skies in Utah, Oklahoma, and Wales England, near the Welsh border, on trips planned for other reasons.

I’m planning to attend the International Conference on Vertebrate Morphology in Punta del Este, Uruguay, this July. Punta del Este is on the coast and I’ll be there for a solid week, so I’m hoping to spend some of my evenings on the beach with binoculars and a travel telescope. I’ve found that I get more out of my observing sessions when I have a list of objects to locate. Fortunately, the Astronomical League has Southern Sky Binocular and Southern Sky Telescopic observing clubs that are deliberately aimed at northerners on quick trips south of the equator. The Caldwell club also includes many southerly objects that cannot be seen from the US, and I’ll try to bag as many of those as possible, too.

Lots of AL observing lists overlap; for example, almost everything on the Urban observing list is also on the Messier, Bino Deep Sky, or Double Star lists. Sometimes you can simplify your work by eliminating duplicate observations. Even when clubs have conflicting requirements, like using binoculars and a scope on the same object, it’s faster to make both observations at the same time by switching between instruments.

To simplify my observing wish list for Uruguay, I compiled a master list that includes all of the objects from the Southern Sky Binocular and Southern Sky Telescopic lists, as well as the 56 most southerly Caldwell objects. I call it Concordiem Australis.  This is a deliberate homage to Stephen Saber’s Concordiem Borealis, which unifies the AL Messier, Bino Deep Sky, Double Star, and Caldwell (70 most northerly) lists with the RASC’s 110 Finest NGC Objects. This version is organized by RA. I will probably also make versions organized by constellation and by declination (for convenience and to match the Caldwell list order, respectively). Here’s the file, which I will also put in the AL Logbook page on the sidebar:

Concordiem Australis by RA

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Mission 19: Cross asterism near NGC 2281

March 4, 2010

Mission Objectives: Asterism, Open cluster

Equipment: Binoculars, Telescope

Required Time: 3 minutes

Related Missions: Diamonds from the Ring of Fire

An asterism is just a pattern of stars that grabs someone’s attention. Asterisms differ from constellations in that they don’t have any official standing, although some like the Big Dipper (which is only part of the constellation Ursa Major) are better known than their host constellations and have been recognized for far longer. Since asterisms don’t have to meet anyone’s standards for asterism-hood, anyone can point one out, and stargazers have been discovering them for as long as humans have watched the skies.

I noticed this one for the first time a few weeks ago when I was hunting down NGC 2281 with my 15×70 binoculars. It’s an easy catch–just find Capella, trace a line to Menkalinan the next star counter-clockwise in the ring of stars that marks the constellation Auriga, and extend the line an equal distance in the same direction. Might as well take in NGC 2281 while you’re there–it’s just southwest of the right arm of the cross.

NGC 2281 is a nice little open cluster for either telescopes or binoculars–another glittering diamond in the celestial Ring of Fire. But in this case, I like the asterism better than the cluster! It’s well worth seeking out, and definitely better in binoculars than in telescopes.

The cross asterism seems really obvious, but I haven’t found any other mentions of it so far. Does anyone know if it has been noted or discussed before? I’ll be grateful for any info.

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Globe at Night 2010

March 2, 2010

We’ve all seen this map. This is why if you’re reading this, chances are better than even that you can’t see the Milky Way at night. For the entirety of human history, everyone everywhere could see more than a thousand stars on a clear dark night. That’s wrecked now, for most of the developed world, thanks to light pollution. And it only took us a couple of generations to do it.

But it would be very easy to unwreck. Our natural heritage in the sky is being washed out by wasted light. Fighting light pollution isn’t about doing away with artificial lighting, it’s about doing away with stupid artificial lighting. Full cutoff bulbs that illuminate roads, sidewalks, parking lots, and front porches contribute very little to light pollution. The problem is unshielded bulbs, which send 50% of their photons up into space. All they’re doing is lighting up the bottoms of birds, bats, airplanes, and satellites. And, not coincidentally, washing out our starscapes.

The bottom line is that unshielded bulbs are wasteful; that’s an awful lot of kilowatt hours we’re sending out into space. Putting a full-cutoff hood on a light doesn’t make it use less energy, but it at least directs all the energy where it’s needed. Or you could use a reflective hood and a bulb that eats half as much power and still achieve the same illumination.

If you want to help fight pollution, there is a very cool project going on now called Globe at Night 2010. All you have to do is go outside, find the constellation Orion, compare your naked-eye view with the GaN magnitude charts, and report your observation using their online form. You can also compare your result with those of thousands of people around the world. If you’re an amateur astronomer, just using the magnitude charts should give you a better idea of how to assess the naked-eye limiting magnitude at your observing site.

Globe at Night 2010 is running from March 3-16, so even if it’s the rainy season where you are, you will hopefully get at least one clear night. It’s fun, it’s easy, you help the human endeavor, and you learn a little something. Go to it!