Archive for the ‘Observatories’ Category

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Mt Wilson 60-inch telescope model by Barry Crist

September 18, 2012

I bought a new telescope–my smallest yet.

The 60-inch telescope at Mount Wilson not only played a big role in the history of astronomy, it also played a big role in my history in astronomy (see this and this). So I was happy to get one of the last models of the grand machine made by miniature telescope maker extraordinaire, Barry Crist.

Yes, there’s a mirror down there. Two, in fact–a primary mirror and a tertiary to send the light out the side of the scope to the eyepiece.

There’s the tertiary mirror lurking amidst the faux ironwork. There’s also a secondary mirror up at the front end, but I couldn’t get a clean shot of it. The mirrors aren’t image-forming and the eyepiece is just a painted plug, but still–little mirrors! So cool. And as the photos show, the little equatorial fork turns in both right ascension and declination.

And there’s the maker’s serial number cleverly hidden away at the back of the fork.

Unfortunately, these aren’t available anymore. I got one of the last three, and apparently Mr. Crist has no plans to make any more. There are still a few models of the 100-inch Hooker telescope available, which is made to the same scale as the 60-inch. Details here, while they last.

The miniature 60-inch and 100-inch telescopes by Barry Crist. Photo from the Mount Wilson Observatory website.

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The pilgrimage to Palomar, constellations by DSLR, and the Azusa fire

September 3, 2012

I have been fortunate to visit two of the great research observatories in California: Lick Observatory on Mount Hamilton, overlooking San Jose, which got me into all this in the first place; and Mount Wilson Observatory, where I’ve gotten to observe twice with the 60-inch telescope.

For a long time I have been meaning to get to the third major research observatory in California: Palomar. The building of the 200-inch (5-meter) telescope during the Great Depression was one of the first scientific “megaprojects”, something akin to the Apollo program or the search for the Higgs boson, and it caught the public interest in much the same way. After serious war-related delays, the great machine was finally dedicated in 1948, had its official first light in 1949, and started regular research observations in 1950–a program that continues to this day. The 200-inch telescope was absolutely the world’s largest telescope from 1948 to 1976, and effectively the world’s largest telescope until the first Keck telescope came online in 1993. The 6-meter Soviet BTA-6, which was completed in 1976, was more of a publicity stunt than a functional instrument and has not lived up to its potential, although I hear it is being overhauled so maybe that will finally change.

If you are remotely interested in the history of big telescopes in general and the history of the 200-inch in particular, I highly recommend The Perfect Machine, by Ronald Florence. If I started relating all the interesting anecdotes about the building of the telescope, we’d be here forever–it will be faster and more enjoyable to read the darn book.

Anyway, yesterday I was staring down the barrel of a 3-day weekend with no definite plans. I decided that it was finally time to go see the “big eye” at Palomar Mountain. London and I didn’t get on the road until early afternoon, so we got down there too late to visit the observatory yesterday. Instead, we went to nearby Palomar Mountain State Park for a phenomenal sunset and some early evening stargazing.

I had along a new toy: Vicki loaned me her Nikon D70 DSLR. She’s had it for three or four years, I’ve just never used it. It’s been on my to-do list, though, and Kevin’s results on Mount Baldy a couple of weeks ago gave me just the kick that I needed. I have been waiting not-s0-patiently for the full moon to pass so that I could try my hand at photographing constellations.

London in the meadow by Doane Pond, with the handle of the dipper hanging overhead.

After sunset London and I went down to Doane Pond, which sits in a nice little bowl with mountains on all sides. We went on a night hike around the pond, which resulted in us accidentally scaring several bullfrogs and them scaring us right back–few things are more alarming than an unsuspected animal making sudden noisy movement right by your feet in the dark. I also stopped at various places around the pond to photograph the sky, the pond, or the sky reflected in the pond.

I should preface all this by saying that I have no idea what I’m doing. This is my first time using a DSLR, I have no idea what about 95% of the controls do, and if you actually know photography you’d best put your beverage down now so you don’t spit it all over the keyboard. Nevertheless, I have read that one can get passable constellation photos with exposures of  30 seconds or less, and you are about  to see my first round of results.

I’ve been rereading Leslie Peltier’s Starlight Nights. I think of it, and Timothy Ferris’s Seeing in the Dark (the subject of this previous post), as “books about the why”. Loads of books will tell you how to stargaze, but very talk about the actual thoughts and emotions associated with the practice. If you want to know why to stargaze, go read Starlight Nights and Seeing in the Dark. Just be warned–if you’re not a stargazer now, you may be one by the time you’re done (also, if you’re not, I don’t know what you’re doing here, but welcome!).

Peltier writes with great warmth about his favorite stars, especially Vega, which was the first star he knew by name. I’d be hard pressed to name one favorite star, but I have a favorite constellation, and that is Cassiopeia. When I started getting into astronomy in the fall of 2007–almost five years ago, now–Cassiopeia was the first constellation I learned. All that autumn I turned my gaze northeast at dusk and found Cassiopeia first. She pointed me on westward to Cepheus and Draco and ultimately to Hercules and M13. To the south she led me to Pegasus, Aries, faint and frustrating Triangulum, and of course Andromeda and its magnificent galaxy. And following in Cassiopeia’s train as she climbed the eastern sky I found the Double Cluster and Perseus, the Pleiades, the Hyades, Auriga and its nice trio of Messier clusters, and the constellations of winter. Our romance has only deepened as I’ve gotten to know her better, for the velvety black folds of her dress are adorned with star clusters and nebulae almost beyond counting. Naturally, I pointed the camera in her direction first.

My first constellation photo–click through for the full-size, unlabeled version.

This is not a triumph of astrophotography. It’s grainy, it’s too bright, and the composition is not stellar (to, er, coin a phrase). But Cassiopeia is there, and I even see the Double Cluster just clearing the trees.

After paying my respects to Cassiopeia, I turned south, to Sagittarius and the summer Milky Way. Here’s the best of the lot, without labels.

And the same thing with constellations and deep sky objects labeled. Not every bright deep sky object is labeled, only those where I can see at least a smudge or a couple of bright pixels. Still, there are at least 19 DSOs visible in what was probably a 20- or 25-second exposure.

I am really looking forward to trying this under darker skies. It never got truly dark at Doane Pond, because the nearly-full waning gibbous moon rose well before the end of astronomical twilight. I think that without the moon it would have gotten very dark–maybe not stupid-dark like the remote places in the Mojave, but darker than Mount Baldy.

One more: the Big Dipper over Doane Pond, with a couple of its stars reflected in the pond. The pond was about as still as it could be, given the number of big splashes caused by alarmed bullfrogs (and, therefore, ultimately caused by me!).

Two things you shouldn’t mess with. To truly grok the immensitude of the telescope, check out the normal-size, full-width ladder going up one beam on the near side. The fork arms on either side have stairways inside for servicing the drive motors.

Today we went up to the top of the mountain and toured the observatory. Oddly enough, I don’t have a ton to say about this, beyond the obvious things. Which are (1) it’s awesome, and (2) if you live within striking distance, you should definitely go. Get there in time to get tickets for the guided tour–it’s waaaaay better than the self-guided tour, the docents are friendly and know a ton about the telescope and its history, and you’ll get to go up onto the catwalk inside the dome and get a much better view of the scope than you can from the little glassed-in visitor area on the dome floor. You really need to walk under and around the scope to get a sense of how immense it is, and you can’t do that except on the guided tour. I have been around some big scopes, including the 3-meter Shane reflector at the Lick Observatory, and the 200-inch makes all the others I’ve seen look like toys. Even knowing intellectually how big it is, I still walked in and thought, “OMG that’s big.” It’s inhumanly big.

The only downside to the whole trip is that as I was packing us up to leave, I momentarily set my observing notebook on top of the car–and then forgot to get it before we drove off. That’s a bummer. I have almost all of the observations backed up in my digital observing log (a huge Excel file), but the notebook had lots of sketches and there were probably a few object descriptions that I had not logged digitally. There’s a slim chance it will turn up, but I’m not holding my breath.

One final thing: there’s a wildfire burning in the Angeles National Forest above Azusa. It started just this afternoon. London and I saw it when we were coming home on I-15, as a fat pyrocumulus cloud squatting on the San Gabriels like a big evil god. At sunset I went to the top of the Claremont parking garage and watched it for a while. It must have hit a new fuel source around then because as I was watching it took about 10 minutes to go from this:

to this:

While I watched, I saw and heard several helicopters making runs to dump either water or fire-retardant foam. At that time, the fire had spread to more than 1000 acres and percent containment was zero. I’ve been up in the mountains lately and they’re bone dry, so this could be a bad one. My prayers are with the firefighters, and the people whose homes lie in the path of the fire.

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Observing report: An entirely different kind of virtual star party

August 28, 2012

If you’ve been following this blog or have trawled the recent archives then you know about virtual star parties on Google+, where astrophotographers put up real-time video images of celestial objects and a mixed group of professional and amateur astronomers and interested laypeople chat it up.

Tonight I got to experience a virtual star party of a completely different sort: a binocular tour of the night sky as projected on the dome of the Samuel Oschin Planetarium at Griffith Observatory. I was invited along by Steve Sittig, a good friend who works at the Webb Schools here in Claremont, where he teaches science, serves as chapel director, and runs the observatory. It is a curious lapse in my blogging that I haven’t covered any of the times that Steve and Andy Farke and I have passed an evening playing around observing with the big orange C14 in the observatory dome at the top of the Webb campus. We’ve chased comets and supernovae and had all kinds of fun–but those are stories for other posts.

Anyway, Steve hooked Andy and me up with tickets to this evening’s virtual star party, and a little before 7:30 we marched into the big dome, took our seats, and got our binoculars ready. I also got a few snaps, including this slightly-better-than-Bigfoot-level handheld portrait of the three of us not looking dorky at all.

I really didn’t know what to expect when the lights went down. I didn’t know whether the projector would project actual images of deep-sky objects, or just little groups of star-points that would mimic deep-sky objects, or maybe just the regular asterisms and constellation outlines.

All that uncertainty was dispelled as soon as the lights went down and the stars came out. The presenter directed us to Orion with his red laser pointer and went into some well-rehearsed patter about how it’s a big molecular cloud where new stars are being born. I was off and running. From the first view of the Orion Nebula (M42), it was clear that this was going to be a lot of fun. The nebula was big and detailed and looked pretty darned similar to its actual appearance through binoculars under dark skies.

I have to confess, I didn’t hang around for the whole Orion speech. I had stuff to see. I scanned south into Canis Major to look for the open cluster M41–and it was there, and looked legit. Followed the dog’s tail north and east to look for the closely paired clusters M46 and M47. There was only one glowing thing at their location, but there was something there and it was clearly supposed to be a star cluster, or maybe two close together. M35 in Gemini: there. Up to Auriga for M36/37/38: all there.

And so it went. The presenter did give us a pretty good tour of the northern sky, and he got to a lot of the stuff that I had raced ahead to find, but there was always more. I was shocked at the detail and fidelity of the images. Now, to be honest, not everything was there. A lot of the smaller or dimmer Messiers were not there–I looked in vain for M78 and M79. But I was often pleasantly surprised. M44, the Beehive, was an actual swarm of projected stars, not a hazy picture, just as it should have been. Better still, M67–hardly what one would call a showpiece object–was also there, just a bit to the south. And all of these things were not mere blobs of light, but were individually different and looked pretty much like they actually do through binoculars. It was pretty darned impressive.

I don’t know why I didn’t see this coming, since it was obviously technologically possible: the highlight of the evening was a tour of the Southern Hemisphere skies. We saw the Southern Cross and the Coalsack, the Jewel Box Cluster and the Eta Carina Nebula and the Southern Pleiades. I had seen these things before in binoculars, lying on the beach in Punta del Este, Uruguay, almost exactly two years ago. It was unexpectedly moving to get to visit them again, with binoculars, lying in much the same position in the reclined chair in the planetarium.

After that we came back to the northern skies for the summer highlight objects, which were very familiar since I just saw them last week. We hit the usual suspects: M4, M6, M7, M8, M20, M24, M25, M17. I popped up to the tail of Aquila and bagged M11 (actually in Scutum for any pedants in the audience, but it’s most easily found by following the eagle’s tail). All in all, by the end of the night the presenter had pointed out about two dozen deep-sky objects, and I had found another dozen or so that went unremarked. It’s weird to think that the projector is presumably putting up images of these faint fuzzies all the time, even though most of them are below the threshold of naked-eye visibility. I am going to start sneaking my binoculars into the planetarium on a regular basis.

When it was over, we all went out onto the observatory veranda to see what we could see in the real sky. Between the waxing gibbous moon, the regular LA light pollution, a bit of haze, and the modest aperture and magnification of our instruments, what we could see turned out to be “not very much”. We tried going right up to the fence and putting all the local lights behind us to try for the Andromeda galaxy and M13, but neither was in evidence. Oh well: the observatory staff did warn us that the real (Los Angeles) sky would be an unpleasant shock after the pristine projected sky. Steve said the projected sky was like what you see up in the Sierras, where the sky background is so black and there are so many  stars that it’s easy to lose your way; the bright stars that mark the constellations are simply lost in endless fields of distant suns.

The downside to virtual stargazing is just that: the endless fields of distant suns are not really endless. Using the binoculars allows you to see the projected stars and DSOs more clearly, but not the stars and DSOs between them. You can’t go very deep; there’s an inevitable limit and you hit it pretty fast. The Milky Way does not break up into a visually exhausting never-repeating parade of clusters, nebulae, asterisms, and rich fields of stars; it’s just a bunch of cloudy light projected overhead. You’re not really out there; the marvel is not at natural splendor but at human ingenuity, and you are, in the end, sitting in a big dark room using the world’s biggest sky app. Fun and interesting, for sure, but not nearly as rewarding as the real thing.

But I think that’s okay. Tonight’s exercise was an outreach, designed to get people who have never used their binoculars for anything other than spying on birds and neighbors to turn them skyward and see a few of these awesome things for themselves, and for real. Based on a wholly unscientific sample of personal eavesdropping, I think it was a success.

One final note. I had come across the idea of indoor stargazing before, in a blog post by Stephen Saber. He wrote,

darksky arenas…

I’m going to have some Superdome-sized Bortle-class 8 planetariums built with a projection accuracy to match. Really, really accurate. Open 24/7.
Peaceful outdoors sounds. Always a clear sky waiting. No more frozen fingers. No skeeters. Lunatic Happy Hours. Southern Sky Sundays and Messier Marathon Mondays.
Such an idea might offend a lot of hardcore Purists. Many might come just for the experience. But I really can’t see also faking the observation making any difference to goto users. *sorry. old habits.*
Or maybe night sky coliseums. Huge fields with perimeter walls rising to block local light pollution and outlying city lightdomes.

Would you come?
How far would you drive?
How much rain and cloudcover would it take?
Will preserving an area’s dark skies eventually come to this?

Having now done a light version of this, my answers are:

  • Apparently I would.
  • Um, 45 miles at least.
  • None, just good company.
  • I sure hope not.

So, virtual stargazing: weird, no substitute for the real thing, but still highly recommended. Go if you ever get a chance.

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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!

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Mt Wilson: even better the second time around

June 14, 2010

About a dozen of us from the Pomona Valley Amateur Astronomers spent Saturday night observing with the 60-inch telescope up on Mount Wilson. A really excellent night on the mountain is a Goldilocks affair–you need enough of a marine layer to cover up the lights of LA, but the fog has to stay low enough not to swamp the observatory itself. The PVAA visited Mount Wilson last summer, but got fogged out. That worked out okay for me, because they rescheduled for the fall and I found out about the trip in time to go along.

Saturday night the marine layer was looking  pretty good when we got there. Unfortunately, it cleared out before midnight, so the sky was too bright for us to do any serious galaxy observing. But we saw quite a few planetary nebulae and globular clusters, which punch through the light pollution better than most galaxies.

We saw a lot of burnt trees on the way in, from last fall’s Station Fire, which at one point threatened the observatory. The trees by the gate had some light charring down near the bottoms of their trunks, but they hadn’t burned very high or very hot, and I suspect that the fire evidence I saw there was caused by backfires set by the firefighters who saved the observatory.

The 60-inch telescope, largest in the world from 1908 to 1917, is as impressive as ever.

Our first target was Saturn. Although the seeing settled down later in the evening, right after dark the sky was pretty turbulent and that cut down on the amount of detail we could see. Also, and to my immense irritation, I couldn’t get my camera to focus with the optical zoom engaged, so I couldn’t  increase the object size on the CCD as much as I would have liked. This photo doesn’t really do the view justice–in fact, it’s not much better than I’ve done with my 10-inch scope from my driveway (proof here).  Remember that this is a sad comment on the state of the just-past-sunset atmosphere and my finicky camera, and not a slight on the telescope, which is capable of much better!

But things did get better as the evening progressed and we saw tons of cool stuff. Several other people were experimenting with their own digital cameras and that inspired me to try some things I haven’t done before, like photographing double stars. Here is Albireo, a summer favorite that is easily split by even small telescopes.

We started with Saturn and ended with Jupiter; the King of the Planets was climbing in the east as the sky started to brighten before dawn. If you haven’t looked at Jupiter in a while, the Red Spot is actually red again, and the normally-brown South Equatorial Belt has faded almost completely. This is a big switch from the past year or two, when the “Red” Spot has mostly been visible as a white notch in the SEB. It was far and away the best look at the GRS that I’d ever gotten.

The highlight of the evening for me was seeing M13, the Great Globular Cluster in Hercules, and M5, another excellent summer glob, back to back. M13 is probably in most deep sky observers’ top ten, but some people like M5 better, and I’m in that camp. M5 isn’t quite as big or bright, although it comes very close, but it has a much more compact core and the outer stars are arranged in loops and swirls rather than radiating chains. To my eyes, M5 looks like an explosion of stars, in progress. It’s good in my ten-inch scope. It’s phenomenal in the 60-inch.

Last fall we went on a weeknight and I had to leave early, around 3:00 AM or so, to get up to teach the next morning. We also had a considerably larger group, so we didn’t get through as many objects per unit time. Obviously going with a big group is better for the club, but it was nice to have a more intimate group and a shorter line at the eyepiece. I had a heck of a good time, and I plan on going back up every chance I get. If it’s within your means, you should do likewise.

Many thanks to our host and telescope operator for another tremendous evening!

Update: I’m kind of a doofus. If you were wondering why this post is included in the binocular category, it’s because I took my 15×70 bins with me and did some deep-sky observing out of the opening in the dome, while waiting in line for the eyepiece. I bagged four targets for the AL Deep Sky Binocular club, which leaves me with only six more needed to complete that list. But I forgot to mention all of this when I first posted!

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New stuff

November 2, 2009

skymap_smallHere’s something that you need, or even if you don’t need it need it, you’ll probably find a use for: free monthly sky maps, with a chart on the first page and an observing list broken down by naked eye, binocular, and telescope objects on the second page. Everything on the second page is noted on the chart on the first page.  Pretty ridiculously awesome. Expect me to reference these a lot in upcoming missions.

Also, Scientific American has an in-depth report on Galileo and IYA2009. Worth checking out. And speaking of, I took my 4-year-old to what he calls the “Griffick Park Ugzerbatory” yesterday. Here he is with a replica of Galileo’s telescope.

Galileo telescope

Believe it or not, new mission coming soon. Hang in there.

 

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Mt Wilson in the clear?

September 2, 2009
Martin Mars tanker flies over the dome of the 100-inch Hooker telescope on Mt Wilson.

Martin Mars tanker flies over the dome of one of the CHARA array telescopes the 100-inch Hooker telescope on Mt Wilson.

Yes and no. No because the Station Fire is still a going concern and one front of it is still on the move in the Mt Wilson area. Yes because there are lots of firefighters up there now and the Mt Wilson pumps have been repaired, so the firefighters have access to 750,000 gallons of water on site. That’s equivalent to 100 Martin Mars drops or 37.5 drops by the 747 supertanker. Also, a series of backfires around the observatory has cleared a lot of the fuel from in front of the advancing Station Fire.

The fire has put Mt Wilson back in the public eye. Astronomy has a great article on the history of the observatory and some of the cool ongoing projects there, and the LA Times has a nice op-ed piece about the observatory’s importance. Internet lines to the mountain are out, so the observatory has a backup website with regular updates here. Also check out some amazing photographs of the current LA area fires here, here, and here; image at top from that last link.