Friday, March 04, 2005

Imaging Saturn...slowly improving

I am slowly improving my images. This is the best single frame image I took tonight.



I removed the light pollution filter to get more natural colors. It's mostly useful for faint objects anyway. This image was captured using a 9mm Plossl eyepiece, in manual mode on my Cannon G1 at ISO 50, full zoom, F 2.5, 1/6th of a second exposure, manual focus on the camera set to focus as close as possible, and then manually focussing using the telescope.

I think I need to get a web cam CCD imaging device to remove the issues concerning transient changes in viewing conditions (jet stream/house thermals etc.). At least the images are getting better! Still, nothing like what I can see by eye through the scope though.

Thursday, March 03, 2005

How do you dew?

Having lost an observing session the other week to "dew" on the corrector lens of my Schmidt-Cassegrain telescope (a common problem with these scopes). I decided to jury rig myself a cheap and effective dew shield. Indeed, it also serves as a comfy back mat if you decide to sleep under the stars next to your telescope (It was between -10 and -14 C tonight here so that was not an option). I fashioned my dew shield from a trusty RidgeRest back mat that was hiding in the basement. All it does is to insulate the corrector lens from the vast sky that pulls heat from the lens (radiative transfer), limiting the heat losses to just the local region of sky I am look at. Here is a photo of my scope in its (crappy) viewing position.....trees, houses, not enough sky.



Anyway, tonight was a comedy of errors.

No sooner than I had done a three star alignment, some insurgents created a weak electrical connection to my battery and the scope died. Once re-powered, I aligned again and then had the bright idea to collimate my scope. I took shifts (tours of duty) out in the cold collimating the scope...get warm, try again, get warm then did a three star align.

Finally, I had captured Saturn in the eyepiece and observed for a bit....Mission Accomplished! I Went inside to get warm, and when I returned Saturn had fallen below the tree tops. I steeled my hunt and noticed that I had another patch of snow-free deck to the east that might provide some viewing opportunities (my patio table had a patch of clean deck under it). So I cruised over there and proceeded to lift my patio table and replanted it into the snow off to the side. With the scope planted in this new location I could no longer see Polaris. Having lost my bearings, I pointed the mount roughly north and relied on shaky communiqu├ęs from my hand controller. I was able to find the stars it needed to do a three star align...Saturn I commanded, and Saturn appeared. I rapidly took lots of images.... unfortunately they were all overexposed. In a final bust of glory, I overexposed Saturn and took this shot revealing four of her moons!



The moons were identified based on the Solar System Simulator that NASA provides. This is it's prediction for the time that the photo was taken.

Then the dew beat my shield........and I began to question the validity of the Geneva Observing Conventions. It would be nice to get rid of some of these trees, but I don't think my neighbors would appreciate it.

Monday, February 28, 2005

Freeware & Shareware for Astronomy on MacOS X

I have been searching for freeware, shareware and open source Astronomy software that I find useful on MacOS X (my computing platform of choice) and I though I would share what I have found with you. This post will get updated as I find new software that is useful to me.

Planetarium, telescope and camera control:


Astroplanner observing session planner and scope control software
License: freeware, commercial version with extra features
Platforms: MacOS X, Windows

Equinox planetarium, telescope and cameral (SBIG) control software
License: Shareware
Platforms: MacOS X

Stellarium Excellent simple to use planetarium software.
License: GPL, freeware
Platforms: Linux/Unix, Windows and MacOSX

XEphem Planetarium, skycharting, telescope, camera and observatory control, many additional features.
License: Custom open source freeware license and commercial version
Platforms: Linux, FreeBSD, MacOS X, Solaris, AIX, HP-UX, Windows (using Cygwin)

iCCD software to control a Starlight CCD camera in MacOS X
License: freeware
Platforms: MacOS X

Image processing and stacking software:


Lynkeos Image stacking, flatfield and darkfield correction
License: GPL, freeware
Platforms: MacOS X

Kieth's Image Stacker Image processing for webcam astrophotography
License: Uncrippled shareware
Platforms: MacOS 8,9,X

Astroyacker Image stacking software
License: freeware
Platforms: MacOS X

Graphic ConverterThe king of shareware! The best image format conversion program alive, also good image manipulation abilities. A must have!

Professional image analysis software


IRAF Image reduction and analysis facility. Professional astronomical image analysis software
Category: License: open source, freeware, custom liscense
Platforms: Unix, Linux, MacOS X, Solaris

Starlink Meta collection of professions image reduction and analysis software and utilities. Also see this page on Starlink and MacOS X
License: mixed, freeware
Platforms: Unix, Linux, MacOS X

Scisoft another integrated package of professional image reduction and analysis softwares
License: mixed, freeware
Platforms: Unix, Linux, MacOS X

Miscellaneous programs of interest:


APOD grabber Little app that grabs the astronomy picture of the day from NASA.
License: freeware
Platforms: MacOS X

DarkAdapted control the screen gamma to retain dark adapted eyesight when observing
License: freeware
Platforms: MacOS 8,9,X, Windows

Celestia Universe simulator, highly flexible many add-ons
License: GPL, freeware
Platforms: Windows, MacOS X, Linux, Unix

Cosmic Debris menu item to predict Arorae Borealis events
License: donationware
Platforms: MacOS X

MoonMenu Menuitem with information on current and future moon phases
License: shareware
Platforms: MacOS 8,9,X, Windows

Mars24 A graphical mars sunclock app that shows the sun relative to the MER rover positions.
License: freeware
Platforms: Linux, MacOS X, Windows

Stargazer's Delight planetarium software
License: shareware
Platforms: MacOS 8,9,X

Scope Calculator calculate FOV, magnification and more
License: freeware
Platforms: MacOS X

Last and certainly not least:

Midnight Mars Browser downloads, manages and creates color images and anaglyphs from the MER rover imagery.
License: freeware
Platforms: MacOS X, Windows

Sunday, February 27, 2005

Clear, Cold & Dark

The perfect sky, no planes
No cries
North of 49
An open field, the ice cracks
A snowmobile rat-a-tat-tats...
Cold Sky

A quiet night, an owls flight
Silence broken,
The hunter has woken
He draws his sword, to be ignored
In the city
Full of lights

In this clear cold dark sky
Frozen tear,
Touches my ear
Saturn passes eloquent
Clear, cold
Dark, Sky

Skyscrapers rise, people writhe
Walk in the park,
Play chess with my heart
Mars, Mars, Opposition
Forgotten, dark
Cold Sky

I pleade, look!
Beside the twins!
Forget what you have sinned
May you rest in the heart
The bosom, of a cold, dark
Clear Sky

Y

Wednesday, February 23, 2005

Third Night of Observing

Had my third night with the scope last night (tonight?). Shoveled the snow off the deck, dragged the scope out and got it polar aligned. The skies were quite good tonight but the moon is nearing full and that hurts the night vision, especially when you look at it directly through the scope ;-) I decided to take another try at imaging saturn. This time I was using a 15 mm Plossl eyepiece with the Canon G1 and tried various exposure settings. I ended up taking about 20 images that I stacked together into the following image.



Much better than my first attempt at Saturn. I also took a slew of images with a 2x barlow attached which were largely overexposed and Saturn drifted out of the field of view but I did image at least one moon (Titan?). I will have to check in Celestia to see where the moons are relative to Saturn to find out. By the time I got re-geared and filtered to start imaging the moon again, the temp had dropped another 4 degrees to -10 C and I discovered to my shock and horror that I had frost on my collector lens! Viewing was over for the evening. I guess I might need a dew shield/heater and perhaps a bigger battery to power it (I can see why people build observatories).

Anyway, I learn something new each time I go out. The Clear Sky Clocks predict a good night for observing tomorrow, Perhaps I'll try to image the moon tomorrow and see what I can observe of the Messier objects within the limited field of view that my back porch provides (damn trees!).

Wishing you (and me) clear skies!

Friday, February 18, 2005

Second Night (with the scope)

Tonight started well, despite it being a freezing -7 C outside. The seeing conditions were good (for Madison, WI at least), I got the scope set up, polar aligned and the go-to's were working well. The skies were clear and stable, and I decided to take a shot of the moon. I got three exposures completed before my camera battery died....probably due to the cold. [note to self: make sure all batteries are fully charged before attempting astrophotography in the future}

As it happened, my first moon shot was my best, then the camera died and the clouds rolled in. I'm still waiting, hoping for clear skies again tonight but I do not know if I will be able to stay awake until 3 AM when the clear sky clock predicts I will have another window of opportunity, the last for a couple of days, as we are expecting more snow.

Anyway, here is my first moon shot, click on the image for full size.



This image was taken at 81 x, f/10 on my Celestron C8-SGT, Canon Powershot G1, auto focus, exposure, and aperature. A single exposure was taken with a light pollution filter, moon filter, and eyepiece projection using the 25 mm E-Lux eyepiece that came with the scope.

Pretty good really. If the skies clear up tonight, I'll try and get some Saturn or Jupiter shots. My first moon shot is a little out of focus, but then this shot was on full auto, I'm sure I can blur it more with some user intervention, although I hope to be able to do better with manual focus. I could easily imagine spending months trying to capture the moon as accurately as my eye can see it through the scope.

The joy here is to see the moon up close and personal again. A wonderful sky object that is loathed by many astronomers as passe beginner crap (hmmmm)

Clear Skies!

Thursday, February 17, 2005

Midnight Mars Browser

For those of you who are interested in following what the Mars Rovers have been up to on any given day, you can now find out with just a click of a button.

A nearly complete set of raw images from the Spirit and Opportunity rovers are hosted at the Exploratorium web site in a subdirectory. These directories are updated daily (often hourly) with the latest imagery from the MER rovers, typically before the images get posted online at the JPL web site. The only problem is that the images are posted with mystical filenames, and it's a pain to download and organize all the images on your local hard drive (~20 GB total).

Late in the 5th inning, Michael Howard stepped up to the plate, and hit a bases loaded single on his first swing (home runs were hit by NASA/JPL/ESA earlier in the ballgame). He has written the application that all MER fans have been waiting for. It is a cross platform java application called Midnight Mars Browser that goes to the Exploratorium web site and automatically downloads some or all the imagery from the MER rovers based on dates you provide, organizes them into folders on your local drive, generates color images from frames taken with the color filters, and generates 3D anaglyphs from appropriate images. It then creates a slide show for you to browse through the images. Sweet!

This application is simply amazing!!!!

I have created a couple of possible icons for this app shown below. Nothing special, just a couple of images of mars, one with some dropshadowed text overlaid. Here are the 128x128 png files. If anyone likes them feel free to use them.



The icon files for Mac OSX are here: MMB and MMB2. Mars Image credits: NASA/Mars Global Surveyor

Enjoy this app, I certainly do!

Thanks for making it Michael. We MER fans salute you!

edit: fixed grammar, added baseball analogy and I note that OS X users will find my icon adorning the newest release of this awesome software (keep improving it Michael ;-). 2/24/05

Monday, February 14, 2005

NIH Adopts Open Access Scientific Publishing

The scientific publishing industry is in a period of upheaval. There is a growing movement in the Academic community towards open access publishing, a concept pioneered by folks like Michael Hart who founded Project Gutenburg in 1971. This movement has now grown (along with the internet) into a force that cannot be stopped.

The Math & Physics communities got in the act early with their preprint archives and the Biology/Medicine communities have now begun to embrace the concept with new open access journals like the Public Library of Science (PLOS). A useful time line and history of the open access publishing movement can be found here.

Well, the gloves are off now. On Feburary 3rd, 2005, the National Institutes of Health (NIH) issued a new policy statement calling for all publications resulting wholly or in part from NIH funded research to be published in an open access database, PubMed Central, maintained by the NIH. The new policy comes into effect on May 2nd, 2005.

In the immortal words of Bob Dylan "The times they are a-changin!"

First, a short primer on how scientific publishing typically works:

*A government or private foundation or corporation (often a mixture of these) funds a research team to work in a particular area.

*The scientists make a discovery or create a new theory and write a manuscript.

*The manuscript is submitted to a journal for peer review and publication. The journal may be non-profit (typical for Academic Society journals) or for-profit (e.g. the Nature Publishing Group).

*The journal sends the paper out to scientists expert in the subject area who provide a scientific assessment of the significance as well as technical accuracy of the article. This is known as peer review and is typically done for free.

*The editor of the journal makes a (sometimes arbitrary) decision as to whether or not to publish the manuscript.

*The reviewer comments are sent to the authors, who make corrections (if requested by the reviewers). The authors submit a corrected version of the manuscript to the journal, along with a copyright transfer form, signing over copyright to the Journal. Often the author also pays publishing charges for pages printed and color figures (often $500-$1000 per article).

*The journal edits the manuscript to fix grammar, spelling, and format the paper to the style of the printed journal. This copy-edited version, the galley proof, is returned to the authors for final minor corrections and then is published by the journal as the final printed version.

*The authors sign a form that entitles them to a few free reprints (usually 25 or so) and the journal offers to sell the authors additional copies (reprints) of their own scientific work at outrageous prices. The author is usually forbidden to publish the final printed version of the manuscript on the web.

*Libraries pay extortionate prices to the journals for subscription fees to the journals. Only people with personal subscriptions, or have University online access rights, or physical access to libraries with the journals can read the journals.

The new policy of the NIH, although not legally binding (it only requests that NIH funded researchers comply) will likely induce all biological researchers in the US to submit all their publications to the new open access database. There are two reasons for this: most researchers are dependent upon the NIH for some portion of their research funding and you don't bite the hand that feeds you; the vast majority of scientists want people to read their published work and this provides a mechanism for both scientists, and the public at large to do so.

The version of the manuscript that is submitted to the archive is the final version before signing over the copyright to the Journal, the version that has not been copy edited and is solely edited by scientists (authors and peer review). If the journal wishes, they can replace the authors version of the manuscript with the final printed version.

There is a lot of debate as to how this will change the scientific publishing industry. Ironically, the article covering this debate in the current issue of Nature is available only to premium subscribers. The new policy may weaken some journals that rely upon subscriptions and advertising to pay publishing costs (and make profits). This could lead to fewer professional journals that correct grammar, provide commentary articles to clarify scientific findings for non-experts and generally publicize science to the public through the media. I personally doubt this will be a problem as there are only a few such journals (like Nature, Science, JAMA, NEJM, The Lancet etc) and they will likely remain strong for various reasons such as their high prestige and impact factors. I suspect the weaker of the "for profit" journals will suffer. These will likely get replaced with non-profit Journals over the next 10-15 years.

In my opinion, this policy announcement is a major advance. It will bring much more information to researchers at institutions that cannot afford subscriptions to many journals, it will open up vast repositories of information to the public at large and thus will promote the advancement of science. It will likely push "for profit" journals into providing value added services to the community (like media promotion and analysis/commentary and perspective) that make them valuable contributors to the scientific enterprise, and not parasitic leeches on the research budgets of funding agencies.

There are some bigger issues lurking within this policy that will impact the areas of copyright law and interpretation of fair use. I hope other funding agencies and nations follow this example and finally free the primary scientific literature from the shackles of greed.

It is a great great day!

Thursday, February 10, 2005

News Alert: I took a crappy photo of Saturn!

Not much to see here, but had my first night of observing with my new scope the other night and took my first astrophotograph! Of course, it was of Saturn.



I am learning that astrophotography is a demanding hobby and I am very impressed with what others have accomplished and published on the web. None the less, I was quite happy to get an image on my first try using a Canon Powershot G1 in auto mode with a single exposure (lol). The only retouch I did was to level the image in photoshop. Sadly, the image sucks compared with what I could see by eye. Pretty good considering it was eyepiece projection, I was not polar aligned, did not have the right filters, no stacking, no guiding, shooting from a flexible wooden deck, no vibration pads and the scope was wobbling as the image was taken by pushing the shoot button on the camera. I hope to learn enough to get some longer exposure stacks soon, and then move on towards auto guided imaging. So much to learn.

It's a start at the least ;-)

Monday, January 31, 2005

The Four Observers


This Astronomy parody based upon the Four Yorkshiremen skit of Monty Python fame, made me laugh my ass off!

Evidently, I just purchased a Halley's comet era schmidt-cassegrain Celestron complete with 6x30 finder!

Anyway, here is the "modified" skit, penned by Attilla Danko, the creator of the Clear Sky Maps linked at the bottom of this page.

Enjoy it! I sure did. (ROTFLMAO)




The Four Observers


Mike: Ahh.. Very passable, this, very passable.
Richard: Nothing like a 18" goto Starmaster, eh?
Roland: You're right there, Ricardo.
Matt: Who'd a thought thirty years ago we'd all be observing with an binoviewered 18" computer controlled scope in a luxurious roll-off roof observatory big enough for a whole star party.
Mike: Aye. In them days, we'd a' been glad to have a schmidt cassegrain.
Richard: A Halley's-comet era Celestron
Matt: Without a tripod.
Roland: OR or a drive.
Mike: 30mm finder, and all.
Matt: We never had a finder. We used to sight along a seam in the tube.
Richard: The best WE could manage was to sweep at random with 25mm Kellner.
Roland: But you know, we were happy in those days, though we had crappy gear.
Mike: Aye. BECAUSE we had crappy gear. My old Dad used to say to me, "Its not the scope, its the observer."
Matt: 'E was right. I was happier then and I didnt have telrad. We had this tiny observatory with with greaaaaat big holes in the roof.
Richard: Observatory? You were lucky to have an Observatory! We used to observe on the porch, all twenty-six of us, no dome slit. Half the sky was missing and we were all huddled together in one corner just to see down to 35 degrees!
Roland: You were lucky to have a PORCH! We used to have to climb the fire escape to the roof.
Mike: Ohhhh we used to DREAM of of fire escapes to the roof! Woulda' been a Kitt Peak to us!. We used to observe out the bathroom window of a downtown apartment. In the winter, the escaping warm air would cause airy disks to bloat to 20 arcseconds. Observatory. Hmph.
Matt: Well when I say "Observatory" it was only a garden shed with the
door open, but it was an observatory to US.
Richard: We were evicted from our garden shed; we had to go and observe in a sodium-vapor lit hocky rink.
Roland: You were lucky to have a RINK! There were a hundred and fifty of us observing in a cardboard box in the middle of the 417.
Mike: Cardboard box?
Roland: Aye.
Mike: You were lucky. We observed for thee months in the nude in a swamp. We used to have to setup at six in the morning, hack down the bullrushes, drain the swamp, sink the tripods four feet into the muck, collimate for 14 hours, just for a couple of hours of observing. And when we got home our SO would complain about how much we spent on telescopes.
Richard: Luxury! We used to have to set up in the swamp at six in the morning, drain the swamp, cut down trees, scrape mosquitos off of our optical surfaces, sink the tripods 6 feet into the muck, collimate for 16 hours. And we we got home, our wives would sell our telescopes, if we were LUKCY!
Roland: Well of course, we had it tough. We used to have to get set up the previous night, drain the swamp by bailing with our OTAs, re-aluminize our mirrors, and collimate 32 different optical surfaces for 20 hours. And when we got home our SO would accuse us of having sexual relations with a paracorr and divorce us.
Matt: Right ... I had to walk to the swamp, which was uphill both ways, carrying 300 pounds of gear, set up at ten at night, half an hour before I packed up, sop up the swamp with my only copy of Uranometria, pay for parking!, melt sand into glass, sift more sand into abrasives, chew pine trees to make pitch, grind 12 mirrors, collimate for 36 hours, observe with a 1mm eyerelief tasco eyepiece for 3 minutes under a limiting magnitude of -26 in heavy snow showers, and when we got home our SO would spit on our Naglers and run off the editor of Sky&Tel.
Mike: And you try and tell the young observers today that...and they won't believe ya'.
All: They won't..

Credits: Monty Python and Attilla Danko