Archive for the ‘AL Galileo Club’ Category

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Heavens Above

February 6, 2010

Here’s one of those “How did I not blog about this sooner!?” things: Heavens-Above.com. If you’ve heard of it before, it’s probably for the International Space Station flyover predictions, which are indeed great. But the site has loads more useful stuff; it’s basically one-stop shopping for the shallow sky* observing.

*If deep sky objects are multiple and variable stars, clusters, nebulae, and galaxies, then shall0w sky objects are those within the solar system–planets and moons, comets, asteroids, and artificial satellites.

So what’s good there?

First off, loads of info on how, when, and where to spot artificial satellites, including the ISS, Hubble, and Iridium flares. Iridium satellites are part of a big fleet of communications satellites. They have absolutely immense solar panels that produce extremely bright flashes of light, called flares, when they fly over. And there are dozens of these things in orbit, so they fly over fairly often. Flares often get as bright as magnitude -8, and sometimes hit -9.5, which is many times brighter than any planet under any condition, and almost as bright as the first quarter moon. Heavens-Above will tell you when and where to look, you just have to register (free) and put in your location.

Second, finder charts for the brighter asteroids and whatever comets are currently within reach of amateur equipment. If you’re working on the AL Galileo Club and you’ve been sweating how you were going to finish the comet observation requirement, here’s your ticket.

Third, loads of data on the Sun, Moon, and planets, including a cool solar system chart that shows where all the planets are in relation to each other right now (incidentally, this chart shows at a glance why we’re as close to Mars right now as we’re going to get on this pass, but not nearly as close as we get on other passes).

Fourth, an all-sky chart that shows what the sky looks like over your head, right this minute (weather notwithstanding), plus cool charts of all the constellations.

Fifth, whatever other goodies may be lurking in the links I haven’t gotten around to clicking yet. Seriously, just go there, register, and start playing.

I was first directed to Heavens-Above ages ago, and I’ve had it bookmarked forever, but I forget to go there. Not anymore! Late last fall my family and I watched the ISS fly right over our house, almost from horizon to horizon. My wife and I even got to see it through my 6-inch telescope. Even at low power, 33x, which I needed to keep a wide field for tracking, it was clearing a thing and not just a point of light. In fact, there were two bright thingies with a smaller, dimmer thingy between them–the solar panels and habitation modules, respectively. Some amateur astronomers have gotten pretty darn good images of the ISS and often the shuttle with it, using hand-guided telescopes and webcams. I haven’t tried that yet, but one of these days…

I’m telling you all this now because my buddy Jarrod has been checking out H-A, and tonight he went out and photographed an Iridium flare! He writes:

It was BRIGHT.  The prediction was for -8 magnitude, as we were only 2.5 km off the center of the flare, and it was every bit of that.  We weren’t sure what to expect, but it did NOT disappoint.

I set the camera up for a long exposure.  This was 99 seconds at f/11, ISO400 at 18mm.  I cropped the one pic down  to this, the other’s a small version of the full-width shot.  I had the lens as wide as I could get, because I didn’t have much confidence it my aiming.  But now that I know that with the compass and clinometer apps being this accurate (as you can see how close to center it was) I’ll zoom the sucker in next time.

Anyway, it was cool as hell to see.  Sydney [his daughter] really seemed to get a kick out of it (it was REALLY bright and easy to spot).  It was a fun thing to get us all out on the back porch for.

That’s his photo at the top. Now you know what you need to do…whaddaya waitin’ around here for?

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Observing Report: Salton Sea…and Claremont

January 10, 2010

Best-Laid Plans

Since I moved to SoCal and joined the local astronomy clubs, I have done lots of public outreach events and moon and planet parties, but until this past weekend I had never been to a star party. Moon and planet parties are easy; set up your telescope wherever there are people and show them the bright stuff. Light pollution is no problem. Star parties are a different story. If you want to see the faint but beautiful clusters, nebulae, and galaxies, you have to have dark skies.

Both of my local clubs have star parties regularly, but until now there has always been some scheduling conflict or another that kept me from going. But I finally had a shot last Saturday, January 9. The Pomona Valley Amateur Astronomers were going to the Salton Sea, a big saline lake out in the desert south of Joshua Tree.

I spent last week planning the trip, making a pack list (which I need to post sometime), and especially figuring out an observing list. The AL Messier Club is my main observing goal this season, and I am freshly armed with Harvard Pennington’s extremely useful Year-Round Messier Marathon Field Guide, which has finder charts and eyepiece sketches for all 110 Messier objects.

Inspired by Jay Reynolds Freeman, I decided to get as many Messiers as possible with my 15×70 binoculars; those observations would count for both the AL Binocular Messier Club and the regular Messier Club. About 20 or so Messiers are currently too close to the Sun to be observed right now, leaving about 90 viable targets. Knowing how unpredictable observing can be, I decided that my conservative goal would be 20. But I secretly hoped to bag quite a few more, maybe 50 or beyond, which didn’t seem unreasonable if I could just stay up all night. We had some nice clear nights last week, and I was sorely tempted to stay up observing from my yard on a couple of evenings, but I decided to save my energy for the big push Saturday night.

Clouds

Saturday I got up early, got packed, took care of some household chores, at lunch, and tried to get a short nap before I hit the road. I was too keyed up to sleep, but I at least chilled out a bit. I got on the road at 2:00 so I could get to the State Recreation Area campground, where we were meeting, in time to set up before sunset.

I was uneasy on the drive out. The sky was full of cotton, from horizon to horizon. Not low, scudding clouds, but the high cirrus-like stuff. Low clouds I don’t worry about so much; they come and go so fast that it is almost impossible to predict what is going to happen in 20 minutes or 20 miles away. They also tend to have breaks now and then so you can still get some observing done through the sucker holes. High clouds tend to stick, and the spaces between them are usually filled with enough haze to make observing difficult or impossible. As far as I could see, all of SoCal was under a vast tent of high clouds.

A couple of times I almost turned back, but as Timothy Ferris said of observing in Seeing in the Dark, you can’t catch any fish if you don’t get your line wet. And who knows, sometimes things do clear off.

The Sea and the Stars

I got to the campground and found a handful of other PVAA members setting up. Someone had talked to the park ranger, who said that daytime clouds often cleared off after dark. I set up my gear, scarfed a quick supper, and spent about half an hour watching birds. The Salton Sea is a major mecca for shorebirds and birders alike. There were dozens of night herons and a handful of great horned owls nesting in the trees near our campsite, and down at the shore I saw egrets, pelicans, about a trillion gulls, and little shorebirds of more makes and models than I can identify. Sunset was gorgeous, flaming pink clouds behind purple mountains, all reflecting off the glassy surface of the sea, interrupted only by the wheeling and gliding of hundreds of birds.

But enough of that rot! What about the stars? Well, against all odds, they started coming out. First Jupiter, then Deneb in the northwest, then Capella, Betelgeuse, and Procyon in the west, and so on until all of the seasonal constellations were out. The sky wasn’t perfect–there was a thin high haze that dropped the transparency a bit, and the odd plank of  cloud interrupted one or another view from time to time–but in general they were pretty darned good. Looking straight up, I could see the Milky Way easily and the Andromeda galaxy with averted vision, which is my usual test for decently dark skies. I made a couple of sketches for the AL Galileo Club and then started knocking off Messiers.

It was a doomed enterprise. The first few were easy, and I took the opportunity to look at a few showpiece objects through other people’s scopes, and show off stuff in mine, but the longer I hunted, the fewer things there were to see. The clouds were creeping back in. Soon the entire western half of the sky was blocked off. Orion was still prominent, but the haze gradually increased until every star looked like a nebula.

We pulled our chairs into a circle and had a good chat, but by 9:00 it was clear that the sky wasn’t getting any better, and according to the weather forecast, it wasn’t going to get any better. We reluctantly packed it in. I had come prepared to spend the night, but I expected to spend it observing. With nothing to hold me there, I hit the road back to Claremont.

Climbing Mount Improbable

It was not a fun drive back. I’d gotten a measly eight Messiers with binoculars, and one more with my 6″ reflector. That was M29, which was pretty far down into the light dome over LA. And speaking of the LA light dome, for the whole drive back I was under it, the evil pink glow of urban sprawl bouncing off a solid deck of cursed clouds. And curse them I did, vigorously and continuously.

I was holding out a secret hope. Sometimes Claremont is totally socked in, but up on Mount Baldy, less than 15 miles from my house, it’s totally clear. I had already planned to stay up all night and I had all my gear, so why not? I’d run up Mount Baldy and just see. I figured it would be completely either/or. Either the clouds would be high enough to go over the mountains, in which case I’d get nothing, or the clouds would stop on the flanks of the mountains, in which case they’d be blocking the city lights and the mountain would be even darker than usual.

Of course, it was the former. Doubly defeated, I drove home. Got in after midnight, stowed about half my gear, and got ready for bed.

Just To Be On The Safe Side…

I was just about to hit the sack when it occurred to me to wonder if I’d locked the car. I’m forgetful, and sometimes don’t, especially if it’s taken me several trips to unload. So I padded out to the driveway to check. The car was locked after all. More importantly, the sky was almost completely clear. In the 20 minutes it had taken me to unload and shut down, the edge of the cloud deck had come east and cleared my neighborhood. There was Orion, Taurus, Canis Major!

Now, I had just rocked through the open clusters of the Big Dog a few nights ago with my reflector, and I knew they’d be easy prey for with the 15×70 binoculars, and I was up anyway, and I needed a win. So I pulled on some sweats, grabbed binoculars, atlas, logbook, and red flashlight, set up a folding chair in the middle of the  driveway and got to work.

I quickly knocked off the Pleiades, M45, which would have been an easy catch at the Salton Sea but which I’d passed over in favor of harder targets. I ‘d figured I could pick it up later, any time the sky was clear. There on the driveway at one in the morning turned out to be just the “later” I needed. Then M41, a bright and easy cluster in the heart of Canis Major. Then M44 and M67 in Cancer, and I was off and running.

I didn’t find everything I looked for. The clouds were gone but the normal LA light pollution was still there. The effect of magnification is to spread out the background sky, thus making it darker, so to some extent you can fight light pollution with magnification. This works well with open and globular clusters, which are balls of stars in and around the Milky Way. It doesn’t work as well with nebulae and galaxies–magnification can actually hurt, by spreading out their otherwise concentrated light until it’s lost in the skyglow. And increasing the magnification is not an option with standard binoculars. I bagged every cluster I tried for–which is every one that was up at that hour–but failed to get even a single galaxy. I think that will require another trip up the mountain.

Still, in a little over an hour, I’d bagged a dozen Messiers with the binoculars, including a couple, M40 and M48, that I’d never observed with any instrument. That brought me up to 20 for the evening with binoculars, and 21 total, just past my original goal for the star party. I stayed up a little longer to get M5–big, bright and easy–and even longer for M68, which was devilishly difficult in the LA light pollution, but ultimately doable, and called it a night.

I’ll post directions for finding most of these, along with some tips and tricks for observing them from the city. The biggest hurdle is just getting out and trying. In the end, I had a great night and a lot of fun. I enjoyed the company of my fellow astronomers at the Salton Sea, and it was nice to go to bed, finally, full of victory energy and not just hatred for the clouds.

Stupid clouds.

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Galileo Club, Part 3: Callisto in eclipse

November 8, 2009

There were two chances to see a Galilean moon entering or exiting Jupiter’s shadow from California tonight. At 6:22 PM Europa came out of the planet’s shadow, and at 8:50 Callisto went into it. I missed the first one but caught the second one.

I cheated a little bit; in addition to observing the disappearance of the moon at under 20x as required by the rules, I also photographed it at higher magnification in my 6″ reflector.

Now, when I first started observing, there were four little moons, two on each side of Jupiter, and as I watched, the inner one on the right got dimmer and then disappeared. But that requires a little unpacking. If you punch up Jupiter this evening in Stellarium or Celestia (follow the links on the right to download ’em if you haven’t already–they’re free), you’ll see that Callisto was the inner moon on the left as viewed from Earth. It was the inner moon on the right in the telescope because Newtonian reflectors rotate the image by 180 degrees. No big whoop, but if you watch the un-flipped version in Stellarium, the mechanics of the process are a lot clearer.

Callisto eclipse diagram

If you face south to see Jupiter, the sun is off to your right, having just set. That means the shadow of Jupiter forms a cylinder sticking out into space to the left of the planet as viewed from Earth. Since most stuff in the solar system orbits in a counter-clockwise direction* when viewed from above (Earthly north), Callisto must be on the far side of Jupiter from Earth. Callisto came out from behind the planet (1), was briefly visible from Earth, then entered the planet’s shadow (2), and will re-emerge in a little less than two hours (3).

* Neptune’s largest moon, Triton, is a notable exception, and its backward motion indicates that it is almost certainly a captured Kuiper Belt object and not a “true” moon. In fact, it is possible that all of Neptune’s moons are captured objects.

So how did the pictures turn out? Well…the listed time of 8:50 PM turned out not to be the midpoint of the entrance of the moon into the shadow, but the  completion. Which I guess makes sense, but I was prepared to start my observations 10 minutes early and run 10 minutes after. In fact, by 8:40 Callisto was already noticeably dimmer than the other moons, and at 8:50 the show was over. “Noticeably dimmer” in the eyepiece means “almost impossible to photograph”, at least with my setup (Orion XT6 telescope, 25mm Sirius Plossl eyepiece, and Nikon Coolpix 4500 camera). I thought I had missed it completely. My only shot of Callisto this evening:

Callisto 1 - nothing to see

Can’t see it? Neither could I. But I blew out the contrast and look who showed up, if only just:

Callisto 2 - ugly but there

By using that image as a template, I was able to copy, paste, and lightly sharpen my best Jupiter image of the evening, and replace the moon blobs with tiny little brush-dots that approximate their actual size and brightness, to create this much prettier and more representative, but less real, image:

Callisto 3 - too pretty to be real

Jupiter looks lousy compared to previous efforts because I was looking through most of the LA light dome and attendant haze, but still: eat yer heart out, Galileo. One required task down, ten to go!

(If you haven’t bagged a moon eclipse yet, there are still several opportunities this week.)

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Galileo Club, Part 2: Jupiter’s Moons in Eclipse

November 6, 2009

Galilean_Moons

Task #4 for the Astronomical League’s Galileo Club:

4. 1612 – Jupiter’s moons in eclipse: The objective is to show that in addition to the moons being occulted by Jupiter, they also travel through Jupiter’s shadow and are eclipsed. Observe and sketch, noting the timing, one of Jupiter’s moons during an ingress or egress with Jupiter’s shadow. Callisto or Ganymede is the most dramatic. Two observations should be done.  One should be close to when Jupiter is at opposition. The second should be done when Jupiter is at quadrature (90 degrees from the sun). Note how close to the planet the moon is when the event occurred. (Editor’s note: At least two observations and timings are required.)

This is one of the ones that needs to be done Real Soon Now, because the eastern quadrature of Jupiter is this coming Tuesday, November 11. After this Jupiter is going to keep heading west and then disappear into the sun’s glare for a while. Western quadrature won’t be for another six months, and then you’ll have to either get up real early or stay up real late to catch it; western quadrature is equivalent in terms of sky position to last quarter moon.

Unless you want to spend all night watching, waiting, and hoping, you’ll want some idea of when to observe to see the entry or exit of a moon from Jupiter’s shadow. So here’s a list of ingressions and egressions for the next week, taken from Sky & Telescope’s Jupiter moon calculator. Sometimes there is an exit with no entrance, because the moon in question went directly behind the planet as seen from Earth; that’s an occultation rather than an eclipse. Everything is listed both by Universal Time (UT), equivalent to Greenwich Mean Time or London time, and Pacific Standard Time (PST). If you live somewhere else, you can look up your offset from UT at this helpful site.

I’ve never watched one of these events so I don’t know how long they take. Probably worthwhile to start observing 15-30 minutes ahead of the stated time and keep watching until you know it’s over. That blows my titular goal of providing things you can do in 10 minutes, but…whatcha gonna do? Feel free to leave a comment if you make a successful observation. Photo borrowed from here.

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Saturday, November 7, 2009
18:18 UT (10:18 AM PST), Io exits eclipse by Jupiter’s shadow. Daytime for US.

Sunday, November 8, 2009
02:22 UT (6:22 PM PST), Europa exits eclipse by Jupiter’s shadow.

Monday, November 9, 2009
04:50 UT (8:50 PM PST), Callisto enters eclipse by Jupiter’s shadow. Sunday night in the US!
09:30 UT (1:30 AM PST), Callisto exits eclipse by Jupiter’s shadow.
12:48 UT (4:48 AM PST), Io exits eclipse by Jupiter’s shadow.

Tuesday, November 10, 2009
08:52 UT (12:52 AM PST), Ganymede enters eclipse by Jupiter’s shadow.
12:32 UT (4:32 AM PST), Ganymede exits eclipse by Jupiter’s shadow.

Wednesday, November 11, 2009
07:16 UT (11:16 PM PST), Io exits eclipse by Jupiter’s shadow. Tuesday night in US!
15:40 UT (7:40 AM PST), Europa exits eclipse by Jupiter’s shadow. Daytime for US.

Friday, November 13, 2009
01:46 UT (5:46 PM PST), Io exits eclipse by Jupiter’s shadow. Thursday evening for US, probably too early for PST.

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Extended Mission: AL Galileo Club

November 4, 2009

Galileo observing

All right, it’s been a long time since I’ve given you any homework. Heck, it’s been a long time since I’ve given myself any homework. Joining the local astro clubs also made me a member of the Astronomical League, which has loads of cool observing projects available. If you complete an observing project, you get a pin and a certificate, and I want some bling.

(Aside: if you’re interested in astronomy but not a member of a club, find one nearby and check it out. Most clubs will happily let you sit in for free for a meeting or two. The two I’m involved in both have annual family dues of $30, and I imagine most clubs’ dues are not wildly off from that. It’s a small price to pay for the companionship and education you’ll get from fellow astronomers.

If there is no club nearby, the stand alone Astronomical League dues are also $30, and if you don’t want to spend any money, you can still download the lists for almost all of the observing clubs for free.)

Observing lists are good. They give you tangible goals, and a way to measure your progress as you develop your skills. Perhaps most importantly, they give you something to point the scope at. The sky is chock-full of good stuff, but if you don’t know that it’s there or how to  find it, eventually you are going to run out of things to do. If you find your observing getting stale, maybe it’s time to try something new.

So, given that it’s the International Year of Astronomy and that we’re all following in the footsteps of Galileo, what better observing list to start with than the Astronomical League’s Galileo Club? The goal is to repeat Galileo’s observations of the heavens. There are 11 required tasks, and two optional ones. The optional tasks are to observe and sketch an aurora, which is only an option for people at sufficiently high latitudes, and to observe and sketch a naked-eye supernova in the Milky Way galaxy. I’m guessing that last one was included a bit tongue in cheek; as the instructions state, “It should be noted that the last time a supernova was visible in the Milky Way galaxy was in the early 1600’s when Galileo observed one.”

Now, the Astronomical League doesn’t pass out those pins and certificates for nothing. Some of the tasks are comparatively easy, but some are fairly involved (in terms of effort, not equipment), and several require making observations at particular times of the year. If you start now, you can’t possibly finish before next summer, not because you’ll be slammed for the next 9 months, but because one of the observations can’t be made any sooner. So if you’re in, you’re in for the long haul.

Gear

The only requirements regarding equipment are as follows: “All observations must be done at a magnification between 10 and 20. Either binoculars or a telescope may be used. The instrument should be mounted to provide adequate stability. Go-to equipment is allowed.”

Let’s break it down, in reverse. Go-to equipment means computerized telescopes that do the finding for you. I’m surprised they allow that for this club; I think it defeats the purpose of the exercise and I’m going to pretend that it doesn’t exist.

Mounting the instrument shouldn’t be a problem. If you’re going to use a telescope, presumably it came with a mount. If you’re using binoculars, all you need is a cheap tripod and about three bucks worth of hardware; see instructions here.

The first requirement is the toughest: all observations have to be done between 10x and 20x magnification. This is tough because some telescopes can’t go down that low with normal eyepieces. For example, my little Mak has a focal length of 1250mm. The longest eyepiece is can accept is probably a 40mm Plossl (which I don’t own), which would still yield a magnification higher than 30. What to do, what to do? One option is to use a scope with a fairly short focal length, which includes loads of small refractors (from the $20 Galileoscope to thousand-dollar APOs) and tubby little reflectors like the Firstscope and Funscope (both $50), Astroscan, and Starblast.

Another option is to just use binoculars. If you don’t already have some, you can get a decent pair of 10x50s for about $25.

What else will we need? Most of the tasks include the word “sketch”. Sketching at the eyepiece is a good way to build observing skills and it’s probably something we should all be doing more of anyway. But what to sketch on? Lots of folks like to use preprinted observing log sheets that have room to note the date, time, equipment, sky conditions, and observations of the target, plus a circle in which to draw the object of interest. You can find nice PDF versions online for free here and here. The GalileoScope Observing Guide also includes a log sheet, and you should check that out anyway, whether you’ve got a GScope or not.

Schedule

Okay, with optics and observing logs hopefully squared away, we still need a plan. We can’t see everything tonight, or even this month. The nature of each task will determine our schedule:

  1. Naked eye supernova in the Milky Way. Good thing this one is optional; an acceptable star might pop tonight or not for centuries.
  2. Moon features; show that the moon has mountains and valleys. Any time that is not too close to full or new moon is fine, so probably 2/3 of the nights on any given month. Check out the moon phase thingy on the right to see what’s going on and plan accordingly.
  3. Follow Jupiter’s moons through one cycle of their orbits. That’s 17 days of observations. Jupiter is a little farther west every evening and we’ve only got a couple of months before it’s lost in the sun’s glare, so start this one ASAP.
  4. Observe one of Jupiter’s moons disappearing into the planet’s shadow or emerging from it. Two observations are required, one at opposition (when Jupiter is opposite the sun in the sky) and one at quadrature (when Jupiter is 90 degrees away from the sun in the sky). Sky & Telescope, Stellarium, Celestia, and a host of other resources will tell you what to look for and when, but look soon, because eastern quadrature is Nov. 11, one week from today. This one is likely to be tricky so I’ll do a follow-up post on it in the next week, promise (hey, I did!). The next opposition isn’t until next summer, so Jupiter may set the lower bound on how soon one could possibly finish the Galileo Club, starting right now. (That would already be sorted if I’d gotten started a few months ago, but coulda woulda shoulda…)
  5. Orion’s head nebula. This isn’t a “nebula” in the sense we use it today, as a giant ball of gas and dust out in space, but rather a nebula as it was understood in Galileo’s time: a fuzzy patch of light in the sky. In this case, observing the fuzzy patch with binoculars or a telescope will reveal that it is composed of stars. Orion is up by about 10:00 and will be higher and better seen at sundown in a couple of months, so this one can be done anytime between now and, say, March or April.
  6. Praesepe nebula. Another naked eye fuzzy patch (only under dark skies these days, I’m afraid) that will resolve into a pretty star cluster with binos or a scope. Anytime in the spring.
  7. Pleiades nebula. Ditto. Up not long after dark right now, anytime in the next few months is fine.
  8. Saturn’s “ears”. The rings look like ears at the low magnifications available to Galileo (and to us, given the rules of the project). Anytime in the spring. Opposition will be in late March.
  9. Venus phases. These need to be tracked from close to inferior conjunction, when Venus is a very big crescent, to close to superior conjunction, when it is a small dot. Venus is currently a morning star and it’s about to get lost in the Sun’s glare. It will re-emerge east of the sun in 2010 and become an evening star, so the best time to start tracking this is in February or March.
  10. Sunspots. This one is tricky, both in terms of equipment and schedule. The instructions say to make the observations using a filter. Well, filters are expensive and Galileo didn’t use them, so I intend to do this as he did: by using a small telescope to project an image of the sun on a white card (don’t look right at the sun with unfiltered optics unless you’re ready to give up the burden of sight). The tricky scheduling part is that we’re in a deep solar minimum and there has only been one sunspot in the past year, so we’re at the mercy of Sol on this one.
  11. Comet. I know there are several floating around regularly within the reach of small telescopes and even binoculars, but I haven’t observed a comet since 17P Holmes a couple of years ago (which was awesome, BTW). Gonna rain check this one for a while.
  12. Neptune. Observable right now, not far from Jupiter. Along with the Jupiter moon eclipse at quadrature, this is the one most needing immediate attention. Standby for directions (also posted).
  13. Aurora. Optional. I saw it in Montana on a dinosaur dig about a decade ago. Very pretty if you get the chance.

All right, that’s all for now. Gather your gear, print off some log sheets, and I’ll get crackin’ on those Jupiter moon timings and on finding Neptune. There are also some pretty end-of-summer objects we need to see before they plunge beneath the western horizon. Stay tuned.