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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October 30, 2007 Comet 17P/Holmes Last night was the first clear night since the onset of this year's round of California wildfires. The fires started on Oct. 21. On October 23, Comet 17P/Holmes began a spectacular outburst, in which it brightened from magnitude ~17 to ~2.5. (Since a 5 magnitude difference is defined as a factor of 100 in brightness, that makes it 100 x 100 x 100 or about 1 million times brighter). The exact reason for this is as yet unknown, but it may be due to the comet breaking up, releasing or exposing more of its icy interior to sunlight. So last night I shot some images. I tried the Meade 12” LX200GPS with an 0.63x focal reducer, but even with that, the comet was larger than the frame of the camera. Although I now have a more capable Meade DSI Pro II monochrome camera, I shot the comet with my older DSI Color. (“DSI 1 Color”). I used the Vixen ED80Sf telescope, which has a wider field. The raw data was shot in FITS format and I haven't combined the various color channels yet, but here's a stack of 50 luminance images out of 94. Exposure time 4 sec. each.
The brightest white dot near the center is the nucleus of the comet. The comet is nearly on a straight line from the Sun extended outward through the Earth, so if it has a tail (and traces of that are starting to appear in some folks' photos), it is pointed away from us. We are in effect staring right down the barrel of this thing. It is, however, moving outward in its orbit after perihelion passage, which is still twice as far from the Sun as Earth's orbit. As our viewing angle changes, we may see more of a tail. Comet names — 17P indicates that this is the 17th periodic comet discovered; in other words, its orbit brings it back into the inner solar system every few years. In this case, about 7 years. At its farthest, it is 5.18 times as far from the Sun as Earth's orbit — about as far as the orbit of Jupiter. The first comet ever shown to be periodic is, of course, 1P/Halley which returns every 76 years. Last night, the comet was clearly visible with the unaided eye even in my light polluted suburban location. I went outside without a star map, knowling only it was somewhere in Perseus. Sure enough, one of the stars in Perseus didn't look quite right. I went back in and got binoculars, and the comet was clearly visible as a fuzzy ball. October 19, 2007 Helix Nebula While warming up the Meade DSI II Pro camera last night, I shot a series of images of NGC 7293, the Helix Nebula. This is a stack of the best 14 of 43 two-minute exposures through a red filter. Vixen ED80Sf, tracking with Meade DSI Color through 12" Meade LX200GPS. Stacked in AIP4WIN, final tweaking in Photoshop CS.
October 17, 2007 First attempts at color with DSI Pro II I've been spending the last few nights trying to gather enough decent-quality images of M33 through red, green, and blue filters. Here's a first attempt at M33. The colors are still not quite as vivid as I expected, but a few huge Hα regions (upper left, and right center) are clearly visible by their slight pink color. I want more color... (Working on it). The images used to make up this composite are all 1 minute exposures, through the Vixen ED80Sf, while a Meade DSI I color did the automatic guiding through the 12” LX200GPS. Who says all this modern CCD and computer stuff isolates us from the night sky? I basically stretched out on a lawn chair while the setup was gathering photons, and watched the sky. I saw a bright fireball, and a classic UFO — in other words, something flying that I couldn't identify, but was most likely a group of American White Pelicans in a neat V formation. (No need to invoke little green men, which were and remain completely unverified, when pelicans, which can be “verified” at the local marsh any day of the week, will do the job). I checked, yes, they are known to be nocturnal. It turns out that last night, which wasn't terribly clear anyway, the limiting visual magnitude at my well-lit suburban location was somewhere between 4.5 and 5.0. Not quite dark enough to see the Milky Way. Click on the image for a larger, higher resolution view.
October 11, 2007 First light with new camera I received, as a gift, something I've had my eye on for quite some time: a Meade DSI Pro II camera. More details soon, but I wanted to get the “first light” images up quickly. This camera is monochrome; to get color images, you have to shoot through color filters (included), and do some fancy computer work later to combine the R, G, and B channels. I haven't gotten to that yet. But here are some mono images. These were shot through my Vixen ED80Sf, piggybacked on the 12” Meade LX200GPS. Guiding was through the 12” scope, with a simpler Meade DSI 1 Color camera and an 0.33x focal reducer (mostly because that's what's screwed on there now and I'm too lazy to swap it for the native f/10 focal ratio). All of these images are composed of 60 second exposures. The first, of M16, is the result of the Meade capture software sorting and stacking images on the fly. The following two are stacked after the fact in Meade Envisage software with “Drizzle” processing, then reduced back to smaller JPG images for web display. M16, the Eagle Nebula and the “Pillars of Creation” in the center:
NGC 7331:
M33:
October 1, 2007 Scouting for the Dawn Patrol Last week, on September 27, NASA launched its Dawn Mission, to the asteroid Vesta and “dwarf planet” Ceres. (“Dwarf” is such a demeaning, judgemental word; can't they call it a “vertically challenged planet”?) Funny, when I was a kid they were all asteroids, and Pluto was a planet. And 200 years ago, they were called worse: “the vermin of the skies.” So I decided to see if I could image these (should be no problem compared to Pluto, which is way less than 1/100th as bright), and furthermore, show their motion. It turns out that you can see motion in as little as one hour, on both. The surprise is that Ceres is currently showing retrograde motion; as Earth passes it in its orbit, it appears to move “backwards” against the far more distant stars. Ceres and Vesta both circulate about two to three times as far from the Sun as Earth's orbit; Ceres an average of 2.8 times, Vesta an average of 2.4 times. These are quite bright, and could easily be seen in binoculars if one knows where to point them. Vesta is mag. 7.6, about one magnitude dimmer (1/2.5th as bright) as the dimmest stars that can be seen by the typical unaided eye under dark skies. Ceres is slightly dimmer at mag. 8.0. Ceres was the first asteroid ever discovered, on the night of January 1,1800. Its discoverer, Giuseppe Piazzi, not surprisingly, was a monk; in Napoleonic Europe, everybody else would have been partying, or hung over (think back to our own “Y2K” festivities). Vesta was the fourth to be discovered, more than seven years later. Since then, they've been coming fast and furious, and at this writing the Minor Planet Center at Harvard has logged and named/numbered somewhere north of 700,000 of the things, and they keep coming at the rate of up to a couple thousand per month. Here, then, is the time lapse of asteroid 4 Vesta. This was a hard one to get, as Vesta is following Jupiter into the evening twilight, and at my location, it was down in the trees, or even the shrubbery, by the time I got the last of the (unevenly spaced) frames. As with Pluto, these were shot with a 12” Meade LX200GPS telescope, a Meade 0.33x focal reducer, and a Meade DSI 1 color camera. Exposures are five seconds, stacked. Image scale is the same as for the Pluto image of Sept. 28. The Vesta image is slightly cropped to eliminate empty borders. The frames were shot at approximately 7:30, 9:00 and 9:15 PM, before it was lost to sight. Something, most likely an aircraft, flew through the field, causing a vertical streak in the last frame.
And here's Ceres, shot the same night. In this case, due to a lack of suitablly bright, widely spaced guide stars, I had the scope track Ceres itself. Note retrograde motion relative to stars. Shot at one-hour intervals, 1:50, 2:50 and 3:50 AM.
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September 28, 2007 Pluto This past week, Pluto passed very close to a brightish (mag. 8.70) star, SAO 160793 in Sagittarius. The actual moment of the close-pass happened while it was over central Asia (Mongolia, western China, maybe southern Siberia and northern India). Some predictions called for Pluto to pass on one side of the star, and its moon, Charon, to pass on the other. For individuals or observatories with photometry equipment, this near-occultation would provide a good means of checking to see if Pluto has a ring system, as has been speculated (so far, nobody is reporting any results of this event). I figured I'd see if I could capture Pluto, since it was going to be close to a bright guidepost. With a near-full Moon in the sky, I could not see Pluto visually. But my first-generation Meade DSI color camera (an item now on closeout at $99) had no problem capturing Pluto, with only a 5 second exposure time. Three nights were easy; the fourth night, after the pass, I had to shoot through clouds. Even with thin hazy clouds obscuring dim Pluto (mag. 14.0), the camera had no problem capturing it. Here's a time lapse of the four images.
To give some idea of how far we've come in 77 years, here's a link to Clyde Tombaugh's discovery images of Pluto, taken in January, 1930. The telescope he used, at Lowell Observatory in Flagstaff, AZ, still exists. It is a 13" three-element astrographic refractor — not much larger than my own Meade 12" LX200GPS. (The other significant piece of gear in the optical train included a Meade 0.33x focal reducer and a Lumicon UV/IR block filter). Back then, using glass photographic plates, Tombaugh was exposing these for one hour at a time (which was an improvement over the three hours that Percival Lowell had been spending). The glass plates were 14 x 17 inches, giving a field of 12 x 14 degrees — much larger than mine. His fields appear to reach about the same magnitude, but took more than 700 times as long to expose. I let the Meade software drive my scope to track the bright star while I had dinner. Here is the story of Pluto's discovery, in Tombaugh's own words. And here's an American Heritage magazine article. It's an interesting exercise to enter the date, January 23, 1930, into the free skymaping program Cartes du Ciel, set the time for midnight, have it center Pluto, and see the same field Tombaugh was dealing with. In the discovery photos, notice the galaxy he captured, at top center, NGC 2365; it's a star that doesn't look quite right.
September 22, 2007 Why I still won't visit the Griffith Observatory / Planetarium Way back on Jan. 27, I wrote about the heavy-handed new visitor policies at Los Angeles' Griffith Observatory.
It seems it's even worse. The place has not only gone stormtrooper, it's gone Hollywood stormtrooper. Browsing through a 1997 issue of Sky & Telescope, I ran across a reprint of this NY Times editorial., "The End of Dignity," which decries New York's Hayden Planetarium going the theme park route. One friend wrote back "Imagine what LA would have done to it." (Too late...) Here's somebody's blog entry about how, after the renovation, Griffith replaced its science-trained presenters with more photogenic actors. Way to go. Fine way to support the people who struggle to make a career of science, or to inspire young people who look forward to one. I have at least four friends who worked with me at the Adler Planetarium, as operators of the Zeiss planetarium projector. Most of us were not photogenic. All of us had some connection to astronomy, either on a professional, student, or hobbyist level. Of those five, two went on to obtain Ph.Ds and professional careers in astronomy and scientific research; two others are in computers; one is an engineer. We would not be considered for any of the job openings at Griffith. Read that link, especially the reader comments, and see how Griffith not only dumbed down its presentations, but also royally screwed over its loyal staff. The LA Times ran an editorial on this topic. Here's a telling observation:
And They (the scientific community) wonder why kids have no interest in science, and why kids grow up to be taxpayers with no interest in funding science? There's part of the answer, staring at us through the glass of a ticket booth selling overpriced admission to a schlock show.
September 14, 2007 Total Lunar Eclipse, August 28. I finally got around to processing the images I shot of the total lunar eclipse last month. Here it is, in time lapse.
The camera used for this was my Kodak P850 on a tripod. These are all at maximum zoom (maximum optical + maximum digital zoom). This was a very dark eclipse, and I found that I had to switch from ISO 100 to ISO 400 sensitivity as it got darker, just to keep exposure times from getting out of hand and showing star (and Moon feature) trailing. Toward the end of the sequence, the star TYC5807-00441-1, magnitude 7.31, can be seen to the right of the Moon, as the Moon passes it. This really shows how rapidly the moon moves in our sky; frames are nominally 5 minutes apart. The sequence ends at some time past the deepest part of totality, when I ran out of battery. In all, I shot about 120 frames, at various exposure times, ISO sensitivity, and zoom factor. The following wide-field image shot at 3:37 AM shows more field stars. 2 seconds at ISO 400, at maximum optical zoom, equivalent to 35mm 432mm focal length.
These may not all show up on your monitor but the stars are as follows: brightest star in the field, at upper left, is σ Aquarii, magnitude 4.82; to its left is 58 Aqr, mag 6.38 (in other words, barely visible with the unaided eye at a really dark location on a moonless night). Immediately to the left of the Moon, TYC5807-01695-1, mag. 7.01, only visible in binoculars; and the aforementioned TYC5807-00441-1 close to the upper right. September 10, 2007 And still more M27 I just can't leave this one alone. Last night I fitted an 0.63x focal reducer to the Meade 12" LX200 GPS, carefully focused the Meade DSI 1 Color camera (it can take 10 or 15 minutes to get a good focus), and let it rip while I passed out on the couch. The alarm clock rang to remind me to shut down the scope and button everything up. I hand-selected about 100 of the best luminance images (those with the roundest stars), stacked and processed them, and used the R, G, and B layers generated automatically by the camera for the color info. The Luminance images were combined in Meade Envisage using Drizzle for higher spatial resolution; the four images (R, G, B, and L) were combined in Photoshop CS. I do believe this is my best M27 yet.
September 2, 2007 Still trying to improve M27, Dumbbell Nebula Last night I got what I thought were pretty good raw images for M27, the Dumbbbell Nebula. These were shot with a 12" Meade LX200 GPS, polar mounted, 0.33x focal reducer giving (nominally) f/3.3, (I haven't checked the actual plate scale; that comes from precise measurement of the reducer focal length, lens principal plane, and principal plane to imager spacing). The imager was a first-generation Meade DSI Color, a camera that's already obsolete (now on closeout at $99). Images were 15 second exposures, the scope was tracking but not actively guiding during exposures (although it would try to keep a stacking alignment star centered by guiding between exposures). Initially the software stacked 125 frames. For this multi-layer composite, I used the 125 frame color image generated by the software but used a Luminance layer with tightened quality criteria, so the L image has fewer staced frames. I used the "drizzle" feature of the DSI software, as described by Matt Taylor in his tutorial DVD.
A friend took that image and looked up the area in sky-map.org (more precisely, this link). It takes a while to load but eventually you can read off data on individual stars by mousing over them (a yellow data box pops up. If it didn't pop up on even the brightest stars, it's still loading, give it a few minutes). It's easier to see faint detail in a negative view; here's the lower portion of the nebula and some faint stars with magnitudes marked. It seems I'm getting down to 18th magnitude – from a well-lit suburban location, on a warm moonlit night with an uncooled $99 camera.
August 16, 2007 OK, now this is stupid.
Bassmasters, look out. Here comes "Extreme Aerial Bowfishing." You think I'm making this up? You think it's a parody of "Skeet Surfing" from the Val Kilmer movie "Top Secret"? (Ya gotta love the lyrics – "If everybody had a 12-gauge, and a surfboard too...") It's apparently an Illinois thing. Here's the Chicago Tribune story. You know those parasite Chinese (what else?) fish that have been making their way into various Midwestern rivers? And how they jump like crazy in boat wakes? Well, it didn't take long for somebody to figure out how to make an "extreem™ sport" out of it. The only added challenge that I can think of is, you should have to tow the shooter behind the boat on a wakeboard. Yes, friends, this has it all. Projectile weapons, boats, motors, big but inedible fish, probably a cooler full of cheap beer somewhere, what Bubba could ask for more? I don't know, I still think dynamite fishing is the techno-geek's answer to a question nobody is asking (like, "how can we kill as many of these worthless critters as possible, with the least amount of effort?) Of course the animal rights whackos are all upset. Oooh, they're shooting arrows through poor defenseless fish. (Apparently they're not so defenseless, as the article says getting smacked by one is like doing a face plant into a flying bowling ball — sort of an act of piscine jihadist martyrdom). All we need now is to have TWO gangs of animal rights activists having at each other, one defending the Chinese crap — sorry, carp; old typing habits die hard — and the other defending all the native species displaced by the carp. The "inventor" of this new sport says
Yeah. He probably figured he'd be shooting his fellow employees first. (Sorry, but I just can't let a setup line like that go unused).
I think they ought to introduce aerial Gatling fishing experiences. You start out as a door gunner in a helicopter gunship. If you're really good, you get to fly an airplane with machine guns in the wings. (Always thinking high tech, that Pete).
I must be living wrong. Do you suppose I could get $250 to teach people how to shoot fish in a barrel?
You know what's coming next, don't you? Get some cameras in those boats! This will make those idiotic "Pro Wrestling" shows look like kids in a schoolyard!
Somehow, I don't think it's a good idea to "face another boater with a bow and arrow." (And all the more reason to go the Gatling route. As long as you go it first).
And once again, it is my solemn duty to point out that Monty Python thought of it first:
Mmmmm... now there's a Bubba Woman... Be still, my heart.
August 6, 2007 Mo' betta Jupiter Tried a new (to me) technique of imaging a planet in color, and then in infrared, and using the IR image as a "luminance layer" in Photoshop. In other words, the color image tells us what color to make any given pixel, but the luminance image tells us how bright to make it. So the sharpness of the resulting image is defined by the sharpness of the infrared image, and infrared is slightly less susceptible to atmospheric "seeing" effects. One little tweak is that chances are, you have to refocus for the two different wavelengths because the filters will change the optical path ever so slightly. This takes valuable time, and with Jupiter, you don't have much time; there's enough rotation in just a few minutes to show up in successive images. So I used a digital focus indicator based on the TeleVue TVFocus system. You find your focus positions beforehand, store those locations in memory, label them with descriptions if you like ("IR filter", "Visual filter"), and when you switch filters, quickly move to the predetermined position and immediately reset and start the camera again. Here's the result. 12" Meade LX200GPS, TeleVue 2.5x Powermate, Atik manual filter wheel, Baader UV+IR block filter and Baader IR pass filter, Philips ToUcam 740K camera, my own custom 2" and T-thread to ToUcam lens mount. Exposure 220 sec. each, 5 frames per sec., about half (~550) of the resulting frames stacked. Captured with K3CCDTools 3, stacked in Registax 4, final processing in Photoshop CS.
And here's another. This was taken later, but I did not use the IR luminance layer technique. The difference between this color image and the previous: I used a shutter speed of 1/50 sec instead of 1/25 sec. This would tend to "freeze" atmospheric seeing rather than give it time to blur. Another run with 1/100 sec did not turn out as well. Somewhere there is a sweet spot between freezing seeing, and reducing your incoming light to the point where you have to increase amplifier gain and so you get more noise. Note also the amount of rotation (the Red Spot has moved). Time difference between these exposures is about 18 minutes. Compare sharpness of white spots in the "South-South Temperate Belt," below and left of Great Red Spot).
July 28, 2007 Jupiter last night Seeing was horrible, but I was trying out some new equipment. Here's Jupiter, shot at native f/10 of the Meade LX200GPS, with a Philips ToUcam 740K. I also tried f/25 with a TeleVue Powermate, but by then seeing had deteriorated even more, and the result was even less detail. Acquired with K3CCDTools3, processed in Registax, final tweaking in Photoshop CS. Stacked 1357 frames of 2404, drizzled to 2x, automatic realignment to compensate for atmospheric refraction. Great Red Spot is clearly visible below center.
Meanwhile, continuing the theme of the past two entries: yesterday afternoon, I shopped at four stores. Two of them, a specialty foods store and a large supermarket, had tellers who had difficulty making change. In one case, the teller was busily chatting with the guy behind me, comparing new wedding rings etc., while trying to process my purchases.
July 18, 2007 More on "The Future of Western Civilization" Perhaps there is hope. The other side of the Home Despot coin. I had to buy some building materials the other day. Now, for this particular item, from past experience, they never have the bar code on the package, and they can never find it in their Big Book of Secret Bar Codes, so the checkout droid flails around, asks if I wrote it down (not my yob, mon; besides, there's five numbers on the stock tag on shelf), phones that department, gets no answer, and often, eventually, picks a similar-sounding (but completely unrelated) product off the computer screen and asks if that sounds about right. Sure, I say. (Usually it means I get my item for half the price posted on the shelf). Well, the other day, I had this item in my shopping cart, headed for checkout, and the girl at the counter saw what was coming toward her in the cart, immediately whipped out a looseleaf binder, flipped to a page of construction materials, found the item, and waved a scanner over it. I said "In four years of buying this product, this is the absolutely first time I didn't have to wait for somebody to figure out what the heck it is. Most don't even know it's in that book." She replied, "Oh, that's not the store's book. That's one I put together for myself." I said "I have a prediction. You're headed for management." She said that actually, yes, she was hoping to. On the other hand, I have seen, I swear, the kid at the local bottle recycling depot (where I have to go to pry my deposit back from the state), I have actually seen this person count how many bottles there are in a six-pack. Out loud. Obviously, not management material.
July 2, 2007 The Future of Western Civilization I just got back from Home Despot, where I got an interesting sneak preview of the future of America and possibly civilization in general. The bimbette at the checkout counter was apparently able to apply eyeliner in a swoopy, artful, indeed almost Egyptian manner, but could not make change for $7.48 out of $10.50 (a $10 bill and two quarters – that's quarters of a dollar, as in 1/4 of a dollar. Two of those. Yeah.) to save her life. In my kind, gentle way I pointed out that this was, at best, sixth-grade arithmetic and hoped she got caught up Real Soon Now. Maybe I should have posed it as a word problem she could understand. On the other hand, perhaps it's a good thing that Home Despot hires the handicapped. That way, checkout duties won't someday be passed off by means of a cheap video link to Bangalore, India (where, unfortunately for us, their kids have learned to count money and make change).
June 11, 2007 Carl and Jerry Stories My friend Jeff Duntemann has just released the third volume of the “Carl and Jerry Stories” from the pages of Popular Electronics Magazine of the 1950s and '60s. (Disclaimer: like the old Shake & Bake comercials, “An' I hailped.”)
I suspect most of us geeks and gearheads will find them entertaining – sort of Hardy Boys meet Bill Nye the Science Guy. A sample chapter may be found here. The Carl & Jerry stories are similar in concept to a long-running series in Popular Science magazine, Gus Wilson and his “Model Garage.” Instead of an electronics theme, Gus' Garage stories are wrapped around clever fixes of automotive problems. Running from 1925 to the final story in December 1970, the stories all carry the byline “Martin Bunn,” who, it turns out, was a catchall nom de plume for a number of hired pens. Those stories are all available online, thanks to a fan.
May 20, 2007 Moon and Venus Last night, on the way to the grocery store, I noticed the conjunction of the Moon with Venus, went back home and shot off some snaps with my Kodak P850, mounted on a tripod. DateTimeOriginal : 2007:05:19 19:44:56 ExposureTime : 1/20Sec ApertureValue : F3.6 ISOSpeedRatings : 200 FocalLength(35mm) : 432(mm) DigitalZoomRatio : 240/100
May 7, 2007 Thermoforming a Hartmann mask For no apparent reason, I got the urge to thermoform a Hartmann mask to assist in focusing for astrophotography through my ED80Sf. What's a Hartmann mask? Lots of info on the web: http://www.astropix.com/HTML/I_ASTROP/FOCUS/METHODS.HTM I wrote up an illustrated html file showing the process. Here's some photos of the thermoforming process using some plywood formers, a heat gun, scrap plastic from a food container; and views of the finished product..
April 24, 2007 The Sun in stereo, from STEREO NASA has just posted some 3D videos of the Sun, taken by the STEREO (Solar Terrestrial Relations Observatory) spacecraft. These are anaglyph images; to view them properly, ya puts on yer cyan-and-red 3D glasses. (You do have 3D glasses, don't you? You don't? Well, you can get them for just a few cents: the cost of a stamped envelope, from these folks). The NASA site has several videos, in your choice of formats: Quicktime, Real Player, and Windows Media Player. You can click on these thumbnails to go directly to the download page for that image. Quicktime takes a long time to load, Windows Media Player is fairly fast.
This will get really interesting when STEREO captures a full-blown major solar flare.
April 4, 2007
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