Archive for May, 2012


Awesome Venus transit simulator

May 29, 2012

In an earlier post I linked to a Venus transit calculator, which is pretty sweet, but now there’s an even better one. Here’s a screenshot:

You put in your location (latitude and longitude, or click the map) and it shows you a movie of the transit from your location with contact times and places (on the limb of the sun) and sunrise or sunset if those interfere. Very slick, and takes a lot of the guesswork out of setting up for the transit. It will even spit out screenshots with a button-click, which is how I got this one. Check it out.


More vacation astronomy: Meteor Crater and Lowell Observatory

May 29, 2012

Last week was full of cool astronomy-related stuff after the eclipse. Monday night I stayed up until after midnight to watch the launch of the Falcon 9, which successfully delivered a Dragon capsule to the International Space Station. Then on Wednesday London and I went to Meteor Crater and Lowell Observatory. The closer, brighter range of hills on the right in the above photo is the rim of Meteor Crater, which rises 150 feet above the surrounding plains.

In the courtyard of the visitor’s center is this boilerplate capsule from the Apollo program. Boilerplate capsules were used for all kinds of testing: parachutes, launch escape systems, touchdowns on land and water, you name it. This is the second one that London and I have seen in the wild–there is also one at the Columbia Memorial Space Center in Downey, California (darn it, I’ve been meaning to blog about that place for about a year now). This isn’t just a random space decoration, either. The Apollo astronauts trained at Meteor Crater with mock suits and backpacks before being launched to the moon.

Here’s the crater itself. It’s too big to fit into a single photo, unless you’re in an aircraft or have some kind of fish-eye lens. The crater is a little over three-quarters of a mile across, and a little under 600 feet deep, not counting the raised rim.

It is extremely windy, too.

Here’s the view to the southwest from the highest observation platform–the platform shown in the previous photo is in the lower middle of this image.

The wind up there was shockingly strong. I’ve been in 60-70 mph winds in desert storms and I think the gusts up there on the rim were about that fast. I’m a big dude, and not used to being pushed around by air, but the wind quite literally sent me stumbling a couple of times. Fortunately there were handholds all over the place.

I set my camera to maximum zoom to get this shot of the fenced area in the center of the crater. If you click through to the full-res version, you may be able to make out an American flag and life-size astronaut standee at the near right corner of the fence. People walking around down there would look like ants.

There was a nice museum inside, which we had to rush through because we spent all our time outside gawking at the crater. I did stop to get pictures of these shattercones, which only form under impact craters and nuclear explosion sites. Shattercones have a nice fractal structure, and range in size from microscopic to tens of meters tall.

That evening we drove up Mars Hill in Flagstaff to visit the Lowell Observatory. This segue photo shows a chunk of the Meteor Crater bolide on display in the observatory.

Flagstaff is a cool place for many reasons, not least the enlightened attitude toward light pollution–or rather, against light pollution. The city is plenty well-lit and never felt dim from ground level at night, but that’s because the residents use their power intelligently, with fully shielded, modestly bright light sources that face the ground. From the overlook on Mars Hill, based on the nighttime lights, you’d think it was a town of six to ten thousand. The actual population is just over 60,000. From the parking lot of our hotel I could see hundreds of stars. I have never seen such dark skies from inside any town of more than a thousand people. And they’ve been doing this in Flagstaff since 1958–when is the rest of the world going to wise up?

Of course, a big part of the reason we went to the observatory was to see the big 24-inch Clark refractor, which has been gathering starlight there since 1896. It looks like a near-perfect miniature of the 36-inch Great Lick Refractor, which also has Clark optics and went into service just 8 years earlier. Percival Lowell used this telescope to chart what he thought were canals on Mars. Lowell’s writings about the ingenious Martians carrying water from the polar ice caps to water their dying world inspired both H.G. Wells and Edgar Rice Burroughs. Both of the latter authors played a big role in shaping my young mind, and I still revisit them periodically, so it was fitting that I finally visit the telescope that made it all possible (even if the canals turned out to be illusory). In a sense, Barsoom was born in this dome.

Speaking of the dome, you’ll notice that it is made of wood and rotates on automobile tires. Those were obviously not part of the original design, but they’ve been in place for decades now. According to Timothy Ferris, who included a charming chapter about this observatory and this telescope in Seeing in the Dark, when one of the tires goes flat, the observatory staff jack up the dome to fix it.

The “smart end” of the telescope looks like some steampunk enthusiast’s fantasy incarnate. It could pass for the control column of the Nautilus. The effect is only slightly diminished by the Telrad perched opportunistically amidst the Victorian gizmos.

I realize that I haven’t said anything about Pluto. It was discovered at Lowell Observatory, but not with this telescope. I’d say more about it but I have nothing to say; I went up Mars Hill for Mars, not Pluto.

This was London’s favorite exhibit: a beach-ball-sized model of the sun filled with little plastic balls representing the Earth, to scale. It’s a fitting cap to this post, because it points the way toward the transit of Venus next week, when those blessed by geography and weather will see an Earth-sized speck moving across the face of the sun (about three times bigger than the Earth-spheres appear in relation to the sun-sphere in this display, since our sister planet’s orbit around the sun is two-thirds the diameter of our own). I may not have time to post again before then, so: clear skies!


Observing report: the 2012 annular eclipse

May 21, 2012

Today rocked. It would have rocked a lot less if things had gone the way I wanted them to. I put off ordering a solar filter for my telescope until last week, and of course everyone was sold out and even the manufacturers were backordered. One is on its way to me, hopefully, but it didn’t arrive in time for our eclipse trip, so I fell back on the sun funnel I built a couple of months ago, and my son’s Astroscan. This turned out to be the perfect combo. In the photo above I was testing the sun funnel in the hotel room, after our long drive from SoCal to Page, Arizona (spread out over 2.5 days, so very civilized and enjoyable, but still a lot of miles).

For the eclipse we set up on the lawn of the Courtyard Inn here in Page. Here’s first contact, when the moon first starts crossing the solar disk. Click for the big version and look at the sunspots–this is the sharpest sunspot photo I got all day.

In addition to the sun funnel I brought a piece of #14 welder’s glass for naked-eye viewing. The eclipse glasses London is wearing were supplied by the hotel when we checked in–I thought that was an awesome thing for them to do, and I told them so.

The middle group of sunspots is getting devoured by the moon.

Almost to second contact, when the trailing limb of the moon crosses the edge of the sun. I like the meta-ness of this photo of a photo-in-progress via a projected image of a projected image.

Just after second contact–we have annularity!

Annularity. This was incredible. I would write more about it, but words fail me.

And here’s why it’s a good thing that my solar filter didn’t arrive on time. If it had, I would have brought my 5″ Mak and left the sun funnel at home. And when the tour bus pulled up 50 feet away and disgorged all these people 5 minutes before totality, they would have missed the eclipse. Thanks to the sun funnel, we had a nearly constant stream of visitors coming by during the first half of the eclipse, and we made some new friends. There’s no way all those folks would have had time to see the eclipse at the eyepiece if I’d been rolling with a solar filter. So from here on out, I’m a sun funnel man. Oh, I will probably also set up a filtered telescope nearby for observing at the eyepiece, but the sun funnel is a key piece of gear, and I don’t intend to voluntarily be without it for future solar events (like the transit of Venus coming up in two weeks).

Third contact–the leading edge of the moon hits the far edge of the sun. See the little points of light between the ‘horns’ of the moon sun? Those are Bailly’s beads, the last rays of sunlight shining through valleys on the limb of the moon. They’re visible at second contact, too, I just failed to capture them in pixels.

I was afraid that the second half of the eclipse would be boring–like the first half run in reverse. It turned out to be a blast. Precisely because we’d all seen it all before (or thought we had–keep reading), we felt free to goof around a bit. Here I removed the sun funnel and put in a regular eyepiece to project the eclipse on my t-shirt. This is a hairy operation–you don’t want to be the projectee and the one pointing the scope at the sun, or you’ll be tempted to glance down into–what? Oh, that’s right, the blindingly intense beam of concentrated sunlight shining out of the telescope. Fortunately I had the presence of mind not to do that, but after this shot, we didn’t let anyone get on the eyepiece side of the scope without eclipse glasses on. This led to some modest hilarity of trying to guide the effectively blind subject to kneel just so beside the scope.

More second-half fun: the sun goes behind an antenna on the next ridge over, maybe a mile away. I suppose a purist might not want anything man-made screwing up the eclipse, but we all thought this was super-cool.

People farther west got to see the entire eclipse, but here the eclipse was still in progress when the sun started to set. Again, some folks might have been bummed but we thought it was crazy-cool to see the sun blocked by both the moon and the Earth. Check out the electrical towers on the distant horizon, much farther away than the antenna in the previous pic. All three sunspot groups are still visible, too.

Moonset at sunset. I don’t even know what you call this…third-and-a-half contact, maybe? Whatever the actual name, we all thought it was the highlight of the second half of the eclipse.

The last sip of sunlight. Good times.

Stay tuned, we’ll do it all over again in a fortnight, only with a much smaller (in apparent size, anyway) object blocking the sun. There’s still time to build a sun funnel and scare up a cheap scope if you’re so inclined. Clear skies!