Archive for the ‘Astronomy Tips’ category

Observation Log 7/20/09: ISS & STS-127

July 20, 2009

The International Space Station, currently docked with Space Shuttle Endeavour, just made a nice pass overhead. Although I have broken clouds at the moment, I managed to get a very nice view.

In the process, I tested a valuable new technique (for me, at least) for spotting ISS passes. I have an iPhone 3GS, which has a built-in clock and a built-in compass. So, I set up several alarms for the sighting (start, highest elevation, and end), noting from Heavens Above what the compass direction would be and putting that number in each alarm. When the alarms go off, I can quickly pull up the compass and know where to look.

This might seem a bit of overkill, except that my attempt to spot the ISS about a week ago failed! I’ve never completely missed it before. The pass was low in the sky and went through skyglow from the city to the north, but I think I should have been able to see it. Anyway, this little trick should help.

If I had unlimited energy and resources, I would love to write an iPhone application that would use the GPS, compass, the timers, and the inclinometers in the iPhone to allow a user to find any sky object (satellites especially) just by pointing the phone at the sky. Words or sounds could indicate which way to adjust the pointing angle (up, down, left, right) to find what you’re looking for. Real fanatics fans like myself could even hold a laser pointer with the phone, to make spotting even easier! Hopefully someone will do that some day soon!

Is this the first-ever picture of an extrasolar planet?

September 19, 2008

It sure looks like it!

The Space Station will make some *great* evening passes next week!

February 9, 2008


Upgrade your Celestron “i” Series hand controller!

February 3, 2008

nx8i.jpgThe only reason I might have purchased a Meade telescope instead of my Celestron was the ability to download updates to the hand controller, such as new comets and such. Good news! Celestron has redesigned their hand controller for their new SkyAlign™ technology, and it also supports downloadable updates. Cool. Even better, I just learned that you can buy the new controller for your “i” series for $150, or send your original and $75 to trade in the old for the new controller. I’m doing it.

More information at the Celestron site. Other Celestrons are also upgradeable, see this page on Mike Swanson’s NexStar Resource Site to learn more.

Update 2/3/2008- As of this writing, Celestron seems to have discontinued the trade-in program. The new controller is now available through resellers for $150. I read in the newsgroups that they aren’t easy to find, at least not yet. Starizona is one outfit that advertises them.

Asteroid 2007 TU24’s close encounter with Earth

January 28, 2008

Asteroid 2007 TU24, discovered only last October, skimmed past the Earth last night at 3:33AM EST (0833 UT) at a distance of 344,000 miles.  It didn’t get as much media attention as I’d expected, and even the astronomy magazines have given it minimal coverage, if any.  Sky & Telescope had a good article which piqued my curiosity.

So, I collected all the data I could find and prayed for clear skies. I expected to be disappointed, so I created a really cool animation of the pass from the point of view of the asteroid, and sped it up 30,000 times. It’s fun to watch.  Unfortunately, doesn’t yet offer a way to include high-quality videos in blog entries, but here’s the best I can do for now.  Sorry about lousy quality and advertising.

OK, that experiment worked out very poorly.  When I watched it, the movie after mine was two young ladies in a smoking fetish video, which I don’t want in my blog.  So here is a link to the good version of the video.  You’ll need QuickTime to watch it.

Wicked rad bonus animation of TU24 zipping by Earth

The illustrations I’d seen showing TU24’s movement as a graceful arc across the sky weren’t and couldn’t be accurate enough to spot the asteroid.  I thought this might partly explain the lack of coverage on TU24—it’s so close to Earth that it’s impossible to print a simple finder chart.  Parallax, an effect of the geometry between two observers’ separate positions on the globe, an asteroid only 44% farther from Earth than the Moon, and the vastly more distant background stars, would shift TU24’s apparent position in the sky too much for even a single US chart to be accurate enough.

Starry Night to the rescue.  Unfortunately, the publisher didn’t release updated with orbital elements for 2007 TU24, so I entered the data myself from JPL’s HORIZONS site and studied the asteroid’s movement for good viewing opportunities.  I read anything I could find in the newsgroups and mailing lists.

We got lucky near Boston MA, and the night sky on 1/28 wasn’t clouded in, as it has been most nights.  So I shoveled off the back deck and put all my optics out there to cool down.  It was 30°F at 4PM, and was supposed to get down toward 20°F.  I also prepared everything I could think of, and left a pile of gear that wouldn’t need cooling just inside the back door.

My plan was to use Starry Night and my laptop to get the Celestron 8i pointed near TU24, then star-hop around to home in on it, using the laptop to track the movement of the asteroid.  This didn’t work.  First, the scope and the program were about a degree apart, and I couldn’t get them to agree.  Second, and I only found this out today, even the latest orbital elements from JPL were another degree off from where it really was in the sky last night.  (Sky & Telescope ran another article today, with pictures taken from Boston.) So, after hours of prep work and almost three hours in the cold, I came within a degree or two.  It’s a little comforting that only two of the three S&T editors could find it. (…though one was using a 5″ scope.  Shhhh!  My unconscious might be listening…)

I learned a few important lessons.  First and foremost, though I’ve done below-freezing observing before, I forgot the cold-weather hiker’s motto: Cotton Kills.  I only had cotton socks on under my boots, and around 10:30PM my feet started hurting in a way I knew wasn’t good.  They felt so cold they felt wet, and I knew I had to get indoors as soon as possible.  Long story short, after 10 painful-to-the-bone minutes having them in lukewarm water, there were no lasting effects.  But, my socks were wet!  From now on, it’s back to poly pro undersocks, and my wicking, hiking socks over them.  How could I forget?

The second lesson was one I had come across in my reading, but mostly ignored.  That is, Don’t Trust Near Earth Orbit Predictions!  An experienced NEO spotter and Starry Night user had said to spot a place in front of the predicted pass, and wait 10 minutes or so for it to come into view.  After an hour of futzing with the scope and the laptop, I took the advice, but to no avail.

The third lesson was, don’t use too-high magnification.  With my 35mm Nagler, I had about a 1° field of view, which was too small. Next time, I’ll use tripod-mounted astronomy binoculars to locate the object.

The last lesson was, Practice Practice Practice!  It was fun and I’ll definitely do it again.  But this isn’t for everyone.  It takes a lot of patience, and even more prep work than usual. That’s probably the real reason why it wasn’t in a lot of magazines.

The Leonid Meteor shower peaks this Sunday; looks to be the best of the year

November 15, 2006

Universe Today is reporting that the Leonids will peak between 11:45PM EST on 11/18 and 1:30AM 11/19. The Earth’s position favors Western Europe and the Eastern US, but it’s definitely worth a check, even on evenings of the 17th and 19th. Look toward Leo for the point of origin of the shower, but the meteors could appear anywhere in the sky. I’ve already seen a few!

Link- Want a Coronado PST right now? I do. That’s how I found

October 28, 2006

Image of Sun in hydrogen-alpha light Discount Telescopes is also a brick-and-mortar store called “Out Of This World” in Mendocino, CA. I found them via Coronado’s site, and they are an authorized reseller. I was calling every company Coronado listed, in hopes of scoring a PST immediately, or at least before Mercury transits the Sun on November 8.

After an afternoon of hearing “we can order it for you,” and seeing web sites that quoted 7 days to 7 weeks until the scope was in stock, I called the “Out Of World” store (800-228-8252, 10:00AM to 5:30PM Pacific Time) and talked to James. He verified the PST was in stock. Woo hoo! Since I wanted expedited shipping, which was going to require he measure and weigh the box, he promised he’d call back with the shipping charges after he finished with a few customers he was helping in the store. He called back when he said he would.

That conversation was the most fun I had all day–not only was the telescope in stock, but we chatted about the upcoming Mercury transit, getting some practice with the scope before then, our Comet SWAN experiences and how it had flared in the previous day, how beautiful CA and Mendocino is, how great and popular the PST is, how I was going to use this scope to introduce my Dad to Mercury, how James suggested trying different eyepieces, and even more. It was a thoroughly enjoyable, personable and professional buying experience, and James clearly knew his astronomy.

I recommend James and Discount Telescopes very highly. My scope should arrive on Thursday, so you can imagine what I’ll be doing that afternoon! And if you also want to get a PST before the Mercury transit, save yourself a lot of time and just call James.

(Disclosure: None. I have no relationship of any kind with this company or its employees, except as a regular, paying customer.)

Update 2/2/2008- It seems that the store no longer sells telescopes, only binoculars and spotting scopes. I sent an email to inquire; I’ll update again if the news changes.

(solar image in hydrogen-alpha light © Greg Piepol,, used with permission)