Covering information that shouldn't be caught out in the open.
Covering information that shouldn't be caught out in the open.
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Clustermap added Oct. 15, 2007
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More better Saturn The atmospheric seeing was a lot better last night, and I got much sharper images of Saturn (compare to March 16 image).
Note the faint purplish C-ring (or “crepe ring”) appearing inside the brightest (B) ring, and stretching about halfway to the ball of the planet. The shadow of the ball on the ring is a lot sharper, as is the dark Cassini Division in the rings. Image details: 12” Meade LX200GPS scope, Philips ToUcam 740K webcam and Televue 2.5X Powermate giving f/24.4. Best 1200 of 2350 frames, 1/33 sec at 5 frames/sec, gamma zero, brightness max, saturation max, contrast 95%, gain 54%. Captured in K3CCDTools 3, stacked and wavelet processed in Registax 4, final adjustments in Photoshop CS. Although it looks like I might have captured the wide, slightly darker Encke Minimum (certainly not the incredibly narrow Encke Division aka Encke Gap) in the outer, A ring, I doubt it. It's most likely a processing artifact. Here's a good description of the rings and what may or may not be captured with equipment like this.
March 28, 2007 More Moon shots Processing some more images from March 24. Here's the "Arago Domes," Arago Alpha and Arago Beta, two apparently volcanic domes near the crater Arago. These are #32 in Charles Wood's "Lunar 100" list of interesting features. The northern one, Alpha, appears to have a large lump sticking out of its top. At the left are the Sosigenes Rilles (Rimae Sosigenes), one of which runs right through Sosigenes A, with half of Sosigenes visible in the corner. Arago has a diameter of about 27 km (16 miles; the domes are 20 km in diameter (12 miles) and of indeterminate height.
And here's the craters Sabine and Ritter, #38 on the Lunar 100 list. The Hypatia Rilles are at the bottom, and the Apollo 11 landing site would be off to the right.
March 24, 2007 To boldly go... ...where this telescope hasn't gone before. This evening, I imaged the Moon, currently at about half phase. Using the excellent freeware Virtual Moon Atlas and my handy copy of Antonin Rükl's Atlas of the Moon, I sat inside at my computer and slowly, remotely, moved the scope along the terminator, looking for interesting features. I finally landed, as it were, at Tranquility Base. Here's the result. Meade 12" LX200 GPS, TeleVue 2.5x Powermate giving f/24.4, Philips ToUcam, captured in K3CCDTools 3, processed in Registax. Four-minute exposure at 5 frames/sec, for 1200 frames; used best 533; final processing in Photoshop CS.
The features are identified in this view. To give some idea of the sizes of these things, crater Moltke is 6.5 km in diameter; Armstrong is 4.6 km; Aldrin 3.4 km, and Collins, 2.4 km. Armstrong and Aldrin are about 83 km or 51 miles apart. The three are #90 in Charles Wood's Lunar 100 list, which is supposed to be roughly in order of increasing difficulty in spotting the features. It's apparent that : 1) there is no way on Earth, that a telescope on Earth can see any trace of the actual landing site, or what's left of the lander (I have to say that because inevitably, somebody always asks). To put it in perspective, the tiniest features visible in this image are on the scale of Meteor Crater, Arizona, about a mile across. As for actually being able to see an astronaut, or the flag they planted, forget it. 2) to get to anything like the Surveyor 5 lander would have meant a hike of 15 to 20 miles each way. The first crew couldn't do that; the later crews, with their Rovers, could, maybe, barely, if the batteries held up that long, but only as a desperation measure; in practice they never got more than 4.7 miles from base. Longest ever traverse was 12.5 miles.
Here's a shot taken from the Lunar Module; the Command Service Module is face-on, above and right of center. Moltke is the large crater at bottom edge, Hypatia Rilles to its left, Apollo 11 landing site is near dead center, near the “messed up” looking triple crater (called “Cat's Paw” by the astronauts; see below). Collins is the large one near top center, right above the CSM and below/left of a crater chain. Gives some idea of what a simple handheld 2 1/4 x 2 1/4 Hasselblad camera can do when 1) you're only a few dozen miles up, and 2) there's no air in the way. From this site.
And, here's the “approach plate” for Tranquility Base. “Sabine D” has since been renamed Collins; “Sabine E” is now Armstrong.
Ahhh, roger, Eagle, you are number one to land, make a left at the boulder field and report short final...
March 22, 2007 Telescopes: not for sissies Just to prove it takes manlymen to handle telescopes: (click on the image)
March 20, 2007 NASA Minister of Fundamental Political Correctness (ret.) is back... Way back on July 23, 2006 I wrote of one George Deutsch, an administration political appointee in the NASA Public Affairs Office who apparently tried to muzzle a respected climatologist. Well, he's back. Space.com carried a report re his appearance in front of a House Oversight Committee investigating whether the administration has interfered with the work of climate scientists.
Saturn last night I spent some time getting really good collimation on the 12” Meade LX200GPS scope, hooked up the Philips ToUcam 740K webcam and Televue 2.5X Powermate "non-Barlow" Barlow lens to give me effectively (measured) f/24.4. Then I focused on Regulus using a Hartmann mask with 1" holes, pointed it at Saturn, and let it rip. Exposures were 8 min at 5 frames/sec, 1/25 sec, with various gain and gamma settings. With gamma cranked midrange, two moons were captured; with gamma zero, I thought the colors were better looking. Images captured with K3CCDTools 3, stacked and wavelet processed in Registax 4, composited and post-processed in Photoshop CS.
The moons are magnitude 10.0 Tethys, at top, and magnitude 9.5 Rhea, at lower left. (Note added April 1: it gets better. See March 31 entry).
February 28, 2007 A new must-have cyber-astro-gizmo While processing some astrophotos I did a search for images of one object and stumbled across wikisky.org. What a neat idea! Think "Google Earth" but for the rest of the extra-Solar-System universe. In other words, everything else. (In the words of the late Severn Darden's character Professor Walther von der Vogelweide, "Vy do ve schtudy ze Universe? Because zer isn't anyzing else!") Wikisky has some neat features. It opens to an all-sky view, which is zoomable. You can search for specific objects (as long as they're not in the Sun's gravitational field; this is not "planetarium software." For that, see Cartes du Ciel). You can toggle a photorealistic SDSS (Sloan Digital Sky Survey) view on or off. You can roll your cursor over an object and a yellow box will pop up with detailed info – name, brightness, etc. Or click on an object and a list abstracts of scholarly articles will appear. It probably does more stuff that I haven't found yet but that alone is pretty neat. Here's a screen shot of the area around the galaxy M96 (useful for identifying just what's what in one's photos of the area):
Some caveats. It doesn't recognize all catalogs. For the Horsehead Nebula, it doesn't know what to do with IC 434 or B 33 or Barnard 33. Type in Horsehead, and it finally announces that that area of the sky hasn't been covered by the SDSS yet. Trying the nearby bright star, Alnitak, will go to the star but with very little detail. Trying M42, same thing, that area is not yet covered. It does, however, offer astrophotos submitted by readers. Besides Wikisky, another fun way to explore the universe without putting on a pressure suit is Google Mars. You can't quite zoom in on photorealistic details as you can with Google Earth, but it's still pretty neat. Here's an infrared view of the caldera on top of Olympus Mons, the biggest mountain in the universe-as-we-know-it.
February 27, 2007 Horse maneuvers I took another shot at stacking and processing film images of the Horsehead Nebula. These were taken on Feb. 14, 2007, just like the Rosette Nebula shown in Feb. 25 entry. Same drill: four exposures, 30 min. each, in well light-polluted suburban Orange County, CA. Kodak Elite Chrome 200. Nikon F3 body on Vixen ED80Sf, piggybacked on 12” Meade LX200GPS. No filters. Autoguiding by Meade DSI Color camera on 12” Meade scope. Images scanned in with some pre-processing (histogram stretch) in Minota Dimage Scan Dual IV scan software, stacked and contrast / color tweaked in DeepSkyStacker (freeware!!!) and post-processed in Adobe Photoshop CS.
Well, now we're getting somewhere. Compare to Feb. 7 (film) and Feb. 22 (digital camera). The digital has better resolution but seems to be lacking in red sensitivity, which is not unexpected as these cameras have a built-in infrared blocking filter. Some people remove the IR block or have a company like Hutech do it for them, and Canon made a small run of their 20D cameras known as the 20Da, with the filter left off by the factory.
February 25, 2007 Film claims it's not dead yet But, in the words from the Monty Python and the Holy Grail segment, “Oh, shut up, you're not fooling anybody.” I got back my film of Feb. 14-15 from the lab, and although it didn't look very promising, I figured I'd go through the motions and try to scan and process the slides anyway. Here's what came out with three stacked images of the Rosette Nebula complex (NGC 2237, 2238, 2239, and 2246) and the embedded star cluster NGC 2244. The apparent size of the red nebulosity is a little larger in the sky than the full moon.
Three exposures, 30 min. each, in well light-polluted suburban Orange County, CA. Kodak Elite Chrome 200. Nikon F3 body on Vixen ED80Sf, piggybacked on 12” Meade LX200GPS. No filters. Autoguiding by Meade DSI Color camera on 12” Meade scope. Images scanned in with some pre-processing (histogram stretch) in Minota Dimage Scan Dual IV scan software, stacked and contrast / color tweaked in DeepSkyStacker (freeware!!!) and post-processed in Adobe Photoshop CS. There is next to nothing of the nebula visible in the original slides, only a few stars. To give some idea of what I was working with, here's the raw stacked image after DeepSkyStacker.
There are some Bok globules visible above and to the right of the central star cluster. Bok globules are clouds of gas and dust, believed to be where new stars are born. Here's a view of this same region taken by somebody who actually knows what he's doing. Jerry Lodriguss is the author of a CD-ROM book I've recommended before, Photoshop for Astrophotographers. But Jerry's image was a 60 minute exposure through a big Astro-Physics refractor, from a dark location on ISO 800 Fuji film that had been gas hypered. Compared with that, I'm amazed I got anything at all.
February 22, 2007 Horsehead again, but with Nikon digital camera I borrowed a Nikon D50 digital camera to compare its results with film (see Feb. 7 entry). On Feb. 19, I shot five 10 minute exposures at ISO 400, through the Vixen scope, using a Meade DSI to automatically guide through the main 12" scope. To cut down on suburban light pollution, I used a 2" Astronomik CLS filter. Well, I guess that settles it, digital beats film.
I shot a roll of 24 Kodak Elite Chrome 200 last week, through the Vixen, mostly 20 minute exposures and before I bought the Astronomik filter. What with the blessed Presidents' Day holiday, the film didn't come back from the lab for nearly a week. When I looked at it, there wasn't anything there worth scanning and processing. I may try again through the Astronomik CLS filter. Or maybe just face up to the reality that film really is dead.
February 7, 2007 Horsehead and Flame with new Vixen scope On January 23, I shot some film images through the main 12” telescope, using an off-axis guider feeding the Meade DSI for tracking, and my Nikon F3 loaded with Kodak Elite Chrome 200 at the main focus. Then I shifted the 35 mm camera to my piggybacked Vixen ED80Sf (see December 20, 2006 entry) and shot more, still using the DSI on the main scope for automatic guiding. The automatic guiding works amazingly well; I didn't have much of a learning curve to contend with. Star images were nice and round in both situations. I shot the Pleiades in Taurus and the Horsehead region in Orion. Here's a stack of two exposures, 10 min and 20 min, with the Vixen scope, of the Horsehead (center) and Flame Nebula (left). North is to the left (the image is on its side, as we would look at the sky with the unaided eye), and the bright star is Alnitak, the leftmost star in Orion's belt (the other two belt stars would extend to the upper left). This has been cropped from the larger full image. Next time, I'll try more exposures, more stacking, and maybe a nebula or light pollution filter. These were shot from well-lit suburbia. With a first-quarter moon nearby, no less.
And here's a much-cropped stack of two images of the Pleiades, just barely showing the reflective dust clouds around Merope (lower right center) and Maia (upper right center). Some stars at left appear double, a stacking, not telescope tracking, artifact (need to rotate one image relative to other). Again, a stack of one 10 min and one 20 min exposure on ISO 200 Kodak Elite Chrome.
And the best part is, I'm doing this from inside, only going out to open or close the shutter, and advance the film. I used to associate the Pleiades with bitter cold. I remember in the winter of 1972-73, I struggled to shoot spectrograms with my home-made 6” f/8 from our snowbound back yard in Chicago. I remember I had to deal with about a foot of snow, and the wind was shaking the scope so badly that I had to make a windbreak out of some sticks and tarps. I got the slitless, objective-prism spectrograms by letting the brightest stars in the sky trail through the field, and then push-processing Kodak 2475 Recording Film as high as it would go. I learned how to develop film for that project. Eventually, to get better tracking, I was able to borrow the keys for the (I think) 10” telescope at De Paul University from my friend Jeff Duntemann, who was a student there at the time. I used the De Paul scope as a mount for better tracking, and just piggybacked my 6” onto it with clamps. My dad helped me drag all the equipment to the university and up to the dome, and patiently stood around, pretending not to be bored, as I shot my images. Just getting to the scope was an experience in itself – up the elevator, past the replica of the “2001: A Space Odyssey” monolith, up the stairs, along the catwalk over the basketball court, into the broadcasting booth, up the ladder, into the dome. I remember that winter. I remember the lights of the John Hancock building and downtown Chicago, only a couple of miles away, twinkling furiously as heat rose off the surrounding rooftops. The dome is still there but there's no telescope in it, the basketball court is gone, and there are offices in its place. Here's how it looks now, shot on a trip to Chicago a couple of years ago.
Why I won't be visiting Griffith Observatory soon
I was looking forward to the re-opening of the extensively, expensively renovated Griffith Observatory in Griffith Park, Los Angeles. I remember driving up to see one of the last shows with the old projector, before they shut the place down to completely gut and rebuild it. It was in early January 2002. I like planetariums. I spent much of my childhood in Chicago's Adler Planetarium, making telescopes and eventually operating the Zeiss Mark VI projector. So now Griffith has re-opened. But I won't be visiting anytime soon. Planetariums are supposed to be welcoming places where people go to contemplate and learn about the universe. The new Griffith setup is anything but welcoming.
Here's all the sorry details.
What the heck? Are they operating on the Southworst Airlines model? Reservations to go see the universe? They expect you to endure a stinkin' shuttle bus ride, pay for it no less, and then find out they're overbooked? At least the airlines give you peanuts. And you get hit in the wallet three times over – parking, mandatory shuttle, admission. Sounds like the Disneyland model – milk 'em for all they've got.
Sheesh. Do they have an official Starship Stormtrooper Uniform? There are reviews online. Some are, inevitably, glowing; but look for the disasters and ask yourself if you feel lucky enough to go there. And, take their hints, avoid the food. Another Wolfgang Puck tourist trap. More negative visitor comments along the same lines. And still more. The one ray of hope in this is that it may be temporary.
Until then, and until they lose the stormtrooper attitude, nuts to 'em. I've got my own telescope, I've got a backyard, the stars are free and I don't need to beg myself for a reservation.
January 13, 2007 More comet. I drove to a hill high above Laguna Beach to shoot the comet. I did some preliminary figuring with various maps, both celestial (Cartes du Ciel could tell me the azimuth at which the comet would set – about 249ish degrees) and terrestrial (old aviation sectional chart told me where I'd have to be on the mainland to see Catalina at about 249ish degrees; it helps that there's a VOR on Catalina with a compass rose already plotted around it; just draw the 69ish degree radial from the VOR, and there you are... or there you should be, if you expect to see the comet set right behind that VOR). So I got the following photos this evening, with the comet following the sun to set behind the southern end of Catalina ("26 miles across the sea" etc.) I thought the town of Avalon should appear in these photos, but it might not be dark enough yet for its lights to show.
Comet just showing in upper right quadrant of frame.
Comet at top center
Comet near center.
January 12, 2007 A daylight comet!!! Right now there's a daylight, sort of, comet (Comet McNaught C/2006 P/1) visible within just six degrees of the sun (6 degrees = about half the width of your fist, held at arm's length). So you can't see it unless something blocks out the sun. Like a house wall, or chimney, etc. Or, in this case, the horizon and low clouds. If you don't block out the sun, "You'll burn yer eyes out, kid." The fact that it's so close to the sun helps to make it one of the brightest in decades – even if it is unfavorably placed. Sunset tonight was allegedly at 5:07 or 5:04 PM depending on who you ask (an astronomy program, or LA Times weather page). The first of these photos was shot right at 5:04. Camera: Kodak P850, on automatic, handheld.
ISO 100, 1/400 sec, f/3.70, 432mm focal length (maximum optical zoom).
ISO 100, 1/250 sec, f/3.70, 432mm focal length + indeterminate "digital zoom"
ISO 200, 1/400 sec, f/3.70, 432mm focal length + indeterminate "digital zoom"
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