Archive for February, 2010


Mission 18: Diamonds from the Ring of Fire

February 27, 2010

Mission Objectives: Bright stars, Open clusters, Messier objects, Star hopping

Equipment: Sky map, Binoculars, Telescope

Required Time: 5-10 minutes per window

Related Missions: Ring of Fire

Introduction: Here on Earth, diamonds are found in the magma pipes that fed long-extinct volcanoes. Sometime in the distant future, the volcanic provinces of the Pacific “Ring of Fire” will be prime diamond-hunting territory. So it’s fitting that winter’s Ring of Fire is also full of diamonds, in the form of open clusters that decorate the winter Milky Way.

All of the clusters described here are within reach of 50mm binoculars, although most won’t show much detail at 7-10x. Even the smaller ones will start to differentiate in 15×70 binoculars, and all of them are stunning in telescopes of any size.

Instructions for M41, M93, M46 and M47: Go outside after dark, face south, and find Sirius. Use it to trace the “doggy” shape of Canis Major. M41 is the biggest and brightest of the clusters in this area, and it’s an easy catch right in the heart of the dog. I usually find it by centering Sirius in the field of view and then just sweeping down (south) through the constellation. It never fails to swim into view. If you’re having a hard time, M41 makes one corner of an elongated triangle with Sirius and a trio of brightish stars along the dog’s back.

After M41, the rest of the Messier clusters around Canis Major may seem a bit anticlimactic, but each has its own charm and they are all well worth tracking down. And there are even better clusters to come.

Although it is nowhere near as brilliant as M41, M93 is one of my favorites. It is small but fairly dense, and at low magnification its irregular shape makes me think of a silvery flame burning in the night sky. To get there, trace your way down the dog’s back to the bright stars Wezen, Adhara, and Aludra, which mark the dog’s hindquarters and tail. If you’re in doubt about which is which, note that these three stars form a right triangle with Aludra at the south end. From Aludra, a loose chain of bright stars trails east into the constellation Puppis. Sweep over and up, over and up, and you’ll see M93. If you get to a star as bright as Aludra, you’ve hit Rho Puppis (looks like ‘p Pup’ in the map above) and gone too far.

The last two in this window, M46 and M47, make a nice contrasting pair. From Sirius, scan east to find the stars that make the back of the dog’s head. I imagine these stars forming one end of a shallow arc that includes several bright background stars and ends on the paired clusters. If that doesn’t work for you, use Stellarium or the atlas of your choice to pick out intermediate stars to use as waypoints. A word of caution: this is a rich region of the sky, with loads of tiny faint clusters that aren’t marked on any but the most detailed maps. More than once I have been looking for M46 and M47 and gotten hung up in the wrong place. If you have any doubt about whether the clusters you’re looking at are the right ones, they’re probably not. One way to recognize them for sure is to note the differences between them; M47 is very sparse with a handful of bright stars in an irregular pattern, whereas M46 has many more stars that are more even in brightness, although none of them are nearly as bright as the most prominent members of M47.

Instructions for M35-M38: Now go to the north end of the Ring of Fire, to the bright star Capella. Use it to trace the 5- or 6-sided (depending on how many stars you include) ring of the constellation Auriga. The side of the polygon opposite Capella is formed by the long line from Alnath (technically in the neighboring constellation Taurus) to the next star clockwise. The clusters M37 and M36 are on either side of that line at the halfway point. Extend the line from M37 to M36 on to the west with a slight bend to the north to find M38. As with M46 and M47, this trio of clusters make an interesting study in contrasts. Here are my notes from Messier Marathon night:

  • M37: compact, dense with faint stars, very rich but dim
  • M36: smallest but brightest of trio, dominated by a few brighter stars
  • M38: intermediate between the other two in both richness and brightness

The first time I observed these clusters, I found M37 and M36 easily and then spent almost an hour trying to locate M38. It just wasn’t there! Then I checked the descriptions of the clusters and realized that I had actually been looking at M36 and M38. I’d been extending the line in the wrong direction. I backtracked and picked up M37 easily–an illustration of why it is useful to know what things ought to look like, and not just where they are.

The Auriga trio are nice clusters, but the fourth and final M-cluster in this window blows them all away. To find M35, trace down the body of the western twin in Gemini, from bright Castor to the swooping arc of stars that marks the outside ‘foot’. Just above the toe of the boot, in a right triangle with the last two stars in the arc, you’ll find M35, a big, bright cluster that rivals M41 in either binoculars or telescopes. If you’ve got a telescope, you can get a twofer–the small, compact cluster NGC 2158 is right next to M35 in the same field. It’s a tough catch in binoculars unless you’re under dark skies, but almost any telescope ought to show it easily. There’s a nice photo of the pair here.

Instructions for M44: I saved the best for last. M44, also known as the Beehive Cluster or Praesepe (“the manger”), is probably the second best cluster in the sky after the Pleiades. But it’s not as easy to find. The Pleiades have enough bright stars to shine out even in suburban skies, but the Beehive is an aptly named swarm of smaller lights. To complicate matters, M44 is located in Cancer, which has no bright stars.

I usually get to the Beehive from Gemini. Here are some methods that might work for you. My usual path is to draw a line from the extended arm of the western twin, through Pollux, and on in the same direction for about the same distance. Right now that line also intersects Mars, so you could cut your travel time by just drawing a line from Pollux, through Mars, to Praesepe. But that method is only going to work for a few days, maybe a couple of weeks at most, because Mars is on the move (compare its position in the map above with this shot from just a few weeks ago). Finally, if your skies are really nasty, you might try drawing a triangle from Procyon, to Pollux, to Praesepe. It won’t be a perfect equilateral, but it’s close; M44 is just above the point of what would be a perfect equilateral.

Or you could do what I often resort to when I’m in  a rush: find the region between the Gemini twins and Regulus, in Leo (just off-screen to the lower left in the image above), and just sweep around with binoculars or your finder. It’s pretty low-fi, but it’s never failed me yet.

M44 is a true showpiece of the sky, with dozens of stars of even brightness seemingly arranged in a net or grid. It can be seen with the naked eye under dark skies, but it really shines in binoculars. As with the Pleiades, it usually looks better in binos than in telescopes, although a short focal length, rich-field scope might have a wide enough field to show the cluster with some surrounding sky for context.

Coda: The nine open clusters in this  mission are just the tip of the iceberg. This section of the winter sky is littered with hundreds more. There are plenty of bright NGC clusters that rival or exceed many Messiers. The region around the ‘feet’ of the Gemini twins is an especially rich area to sweep with binoculars or a telescope at low power, whether you’re hunting for specific targets or just soaking up the view.

Spring is coming. Although the constellations of winter are high overhead at sunset, they are already starting their long slide toward the western horizon. So get ’em while you can.


Lunchtime musings

February 24, 2010

In my first six months with my scope I spent most of my time observing the same double handful of objects. I realized that I was stuck in a rut, so one night I took Turn Left at Orion and a red flashlight out with my scope. I figured it couldn’t hurt to try. I decided to start with something I’d never seen before, but which was supposed to be easy–M41 in Canis Major. It was easy–and beautiful! I saw that M46 and M47 were a short distance away, so I tracked them down. And so it went, from one target to the next. I was too excited to linger on any one object. After a couple of hours I’d seen about two dozen DSOs that I’d never seen before. My final targets were M81 and M82. It was the first time I’d ever seen two galaxies in the same field, and it stopped me in my tracks.

In the two years since that night, I’ve been back to all of those objects and many more besides. Almost every time, I notice something that I haven’t seen before. The more times I observe, the more I learn to see, the more I realize how worthwhile it is to linger on each object for a few minutes and give myself a chance to tease out its details.

The objects that I found that night have become like friends. When I am in their neighborhood, I stop by to see what new impressions I will have. And then I go on to meet their neighbors down the street, and the folks on the next block over. Every observing run is an opportunity to improve my skills, to deepen my knowledge of the sky, to explore and to discover.

What kind of relationship do you have with the objects that you observe? Can you remember what they look like when you’re apart? Are they unique individuals or just a long line of warm bodies? Can you point out where they live? Could you get there with a map?

If someone abandoned you for a couple of hours in an empty field on a clear dark night with only binoculars or a spyglass, would that be too much time or too little?


Mission 17: See an asteroid

February 18, 2010

Mission Objective: Asteroid

Equipment: Binoculars

Required Time: 5 minutes

Instructions: Go to Heavens Above or fire up Stellarium and find the position of the asteroid 4 Vesta. It would be pointless for me to post a map for you, because by the time you read this, it will have moved at least a little. But do it soonish, because tonight–actually as I write this–Vesta is at opposition and thus as close to Earth and as bright as it is going to get this year. Also, right now it is cruising past the shoulder of the constellation Leo, close to the bright stars Algieba (same binocular field) and Regulus (close enough to get you moving in the right direction), which are bright enough that you should be able to see them even through light pollution. Use binoculars because you’ll want that wide field of view for sweeping from Regulus up to Algieba and then finding Vesta. You don’t need a scope for this one because there is literally nothing to see; Vesta is so tiny and so far away that you will not see it as more than a point of light.

While you gaze on this little point of light in your binoculars, you can reflect on the facts that Vesta was considered a planet for about four decades following its discovery in  1807, and that we have pieces of it that were blasted off in an ancient collision and have fallen to Earth as meteorites. (We’re pretty sure that these meteorites are bits of Vesta because they have the same composition.)

Have fun!


Collinder catalog PDF

February 16, 2010

Cloudy Nights has a great article about the Collinder Catalog, a list of 471 open clusters compiled by Swedish astronomer Per Arne Collinder for his 1931 dissertation. There have been requests in the forum to post the catalog as a PDF, so I copied the list and notes into OpenOffice (which is free, and awesome, btw) and exported it as a PDF. I would have simply posted the PDF to the Cloudy Nights forums, but they don’t allow attachments larger than 124 Kb. So I’m putting it here instead.

Please note that this is not my work at all; Thomas Watson did all of the heavy lifting in terms of updating Collinder’s list and turning it into a useful observing too. All I’ve done is convert it into a PDF so people can use it more easily.

Update, October 20, 2010: Thomas Watson posted an updated version of the catalog which corrects some minor errors in the first version. The v2 PDF below reflects those changes. Thanks for the heads up, Thomas–and for the mountain of work! It is certainly a lovely gift to the observing community.

The file:

Collinder Catalog v2


Observing Report: Messier Marathon!

February 14, 2010


My parents got me Harvard Pennington’s The Year-Round Messier Marathon Field Guide this past Christmas, and I have been obsessed with Messier Marathons ever since. I’d never run one; before last night I’d seen fewer than half of the Messier objects (54/110).

(A Messier Marathon is an attempt to see as many of the 110 Messier objects as possible in one night. Although Messier’s list has been around since the late 1700s, no one had realized that it was possible to see all of the objects in one night until the 1970s, and no one succeeded in getting all 110 in one night until 1985. Loads more info here.)

Pennington subverts a lot of conventional wisdom in the book. Before reading the book, I figured I might attempt a marathon some day after I’d seen all the Messiers and knew my way around the sky a little better. Pennington argues forcefully that running a marathon is the best way to learn the sky, build observing skills, and build confidence. In other words, it’s not something you have to work up to, it’s the way you work up to a good working knowledge of the sky.

Also, before reading the book I’d only heard of people attempting marathons in March and April when it’s possible to get all 110 objects. In Pennington’s words (page 3):

Some people go Marathoning only in March…. That is silly. The very next dark of the moon is the best time for you to run your first Messier Marathon.


One of my local clubs, the Pomona Valley Amateur Astronomers, was heading to Death Valley for a big star party this weekend. For various reasons, I was looking for something a little closer to home. Last month the PVAA star party was down at the Salton Sea, but we got clouded out after just a couple of hours. I knew that fellow PVAA member Ken Crowder was also looking for a closer spot and thinking of returning to the Salton Sea, and we planned to meet there yesterday evening. Ken was going primarily for astrophotography, and I was going to attempt a Messier Marathon.

Pennington’s Field Guide was my inspiration and how-to guide. I also wanted an all-sky map showing all of the Messiers that I could use as a roadmap. I found this one on WikiMedia Commons and printed out a color copy on 11×17 paper.* Finally, I used Stellarium to figure out where the horizon would be at sunset and sunrise, to determine which Messiers would be easy, which ones tricky at dusk and dawn, and which ones impossible. I used a black marker to draw the horizon lines on my all-sky printout, and used the marked-up map to figure out a search sequence.

In this I departed a bit from the Field Guide, which has built-in search sequences for every month of the year. These are good and helpful, but in places counterintuitive. Search sequences are critical for catching those objects that are only visible in short windows at dawn and dusk. For the rest of the night, it makes sense to work from west to east in strips and from south to north within a strip (because more southerly objects set sooner than northerly objects at the same right ascension, or sky “longitude”), but the exact order is less important. My decision to depart from the Field Guide sequence was not without consequence.

Strategies for Starting and Finishing

For the twilight rush, I wanted to start with M39, an open cluster near the bright star Deneb in Cygnus. It was the lowest Messier object in the sky at sunset, and thus the hardest to pick out of the twilight glow before it set. I wasn’t too worried about getting M39, because it’s fairly far north and would rise again a couple of hours before dawn. Still, it would be nice to get off to a strong start by picking it up the first time.

After M39, the twilight rush was full of galaxies: M74, M77, the Andromeda galaxy (M31) and its bright satellite galaxies M32 and M110, and fellow Local Group member M33. I was worried about these because galaxies are notoriously difficult in bright skies, and I’d never seen half of them, including the crucial M74 and M77.

At the other end of the night, I was anxious to see how many of the clusters and nebulae I’d be able to fish out of the sky around Sagittarius. This was a special concern because the area around Sagittarius and Ophiuchus holds the densest concentration of Messier objects in the sky–almost a third of the Messiers, in a patch of sky about as big as two outstretched hands. On top of that, they’d be rising just before sunrise. At best, I’d go into the Sagittarius region with 70-odd objects logged; the outcome of the marathon would largely depend on how well I fared that area, at the end of an all-night observing session, racing against the sunrise.

I knew from Stellarium that at least four objects were flatly impossible, because they would never be above the horizon without the sun: M72, M73, M30, and M2. Three more were pretty iffy; M55, M75, and M15 would be flirting with the horizon but deep in the morning twilight. A final three I felt pretty good about; M54, M69, and M70 are at the bottom of the Sagittarius “teapot” and I thought they’d be tough but doable. All told I figured the maximum possible outcome would be 100 objects definitely, 103 probably, and 106 at the very outside.

Setting Up and Getting Going

I got down to the Salton Sea just before sunset and found Ken set up in a parking lot near the campground. I set out my 6-inch Dob and 15×70 binoculars. I’m working on the Astronomical League’s Messier and Binocular Messier observing programs, and I wanted to bag as many Messiers as possible with both instruments (please be aware that the AL does not accept marathon observations for the Messier Club; nevertheless, running a marathon is still good practice and makes finishing the AL observations easier). I also brought a folding chair for seated observing at the scope, a tray table for maps and charts, a camp chair for visitors (which ended up holding the binoculars between looks), and a tripod for the binoculars. Normally I prefer to use the binoculars freehand, and in fact that is how I used them for most of the night, but when searching for tough stuff in the twilight it’s nice to be able to point them in one place and have them stay. I also brought along the basic creature comforts: warm clothing, snacks, and plenty to drink, both water to stay hydrated and energy drinks to stay awake.

The evening rush turned out to be surprisingly easy. M39 was an easy catch in both binos and scope. I couldn’t get M74 in the binos but it was fairly easy in the scope with averted vision. On the flip side, M33–a big, dim, face-on spiral galaxy–was easy prey for the binos and I didn’t try for it with the scope. In retrospect, I think I should have at least tried, but at the time I didn’t want to take any time out of the evening rush for such a notoriously tough catch.

Soon I settled into a rhythm. I used the all-sky map to figure out what to hit next and the Pocket Sky Atlas to figure out how to get there.** I tended to seek isolated targets with the binoculars first and then the scope. For objects in clusters or chains, I needed to be able to leave an instrument on a landmark I could get back to, so I worked out the star-hops with the scope and then chased them up in the binos.

The Realm of the Galaxies

Heading into the marathon, I was sweating the Virgo-Coma Cluster more than Sagittarius, for two reasons. I’d been through most of Sagittarius before, and it’s almost all globular clusters, which are usually easy. Virgo and Coma only have about half as many Messiers as the Sagittarius/Ophiuchus area, but they’re ALL galaxies, very tightly packed and with few bright stars for finding one’s way. Both the Field Guide and the Pocket Sky Atlas have special charts just for the Virgo-Coma “clutter”.

It turned out to be surprisingly nonproblematic. Perhaps it’s because I’ve been doing so many star-hops with binoculars from my driveway, but under the reasonably dark skies at the Salton Sea I found enough stars to guide me through the clutter. It wasn’t fast or fun–including 15 minutes off for a snack and a bathroom break, it took me almost an hour and a half to track down the 16 galaxies in that part of the sky–but I got them all. And all but one with the binoculars, after having found my path with the scope.

A Break

In any Messier Marathon in or around March, there is a spot after the Virgo-Coma Cluster when you’ve seen everything that’s above the horizon, and you might as well knock off for an hour or two while you wait for Ophiuchus and Sagittarius to crawl over the eastern horizon. In the quarter hour leading up to 2:00 AM I fished M12, M10, and M107 out of the dense atmosphere near the horizon, and then decided to call it for a while. I packed everything up and crawled into the car for a nap.

I couldn’t sleep until I had double-checked that I was on track, so I pulled out the all-sky map and started checking off targets based on my log. I had 73 down, but try as I might I could not find more than 36 unseen targets on the map. Somewhere I had missed something. And I had a nagging feeling that the one I had missed was one of Messier’s “mistakes”–a multiple star rather than a cluster. Fortunately, the Field Guide breaks down all of the Messiers by type and includes a special section on these. And there it was, M40, a double star in Ursa Major. I had completely missed it while sweeping up the Great Bear’s galaxies in the early evening. Fortunately it would be high in the sky for the rest of the night so I’d get another shot, but it illustrates the risk of not sticking to a strict, written observing program (M40 was on my map, I’d just cruised right past it).

Sorting that out took the better part of an hour. I planned to get back at it at 4:00. I set my alarm, closed my eyes, and…failed to sleep. Too keyed up, too anxious about Sagittarius. But I did rest.


I got a bit of a late start. After rousing at 4:00, taking a biology break, and re-setting up all of my gear, I didn’t cross off M40 until 4:22. Then I knocked out M57, M56, M29, M27, and M71 in the area around Lyra and Cygnus–the last five objects outside of the Sagittarius snarl. I was back in the groove and went into Ophiuchus and Sagittarius crossing off an object every three minutes.

It wasn’t enough.

Having never seen a sunrise at the Salton Sea–and having seen only a couple of sunrises from any observing field–I had tried to guesstimate how late I could go from Stellarium. I knew the sun would come up at 6:40 AM, and I figured I could push through to about 6:00. Imagine my distress when at 5:20 I saw the sky getting bright in the east. I trucked on through the “steam” rising from the Sagittarius teapot, but I was getting desperate. Shooting up to Scutum and the “tail” of Aquila, the Eagle, I could not find M26 in the brightening sky. My final object was M11, the Wild Duck Cluster, which was an easy catch in binoculars at 5:38. I wanted to get it in the scope, too, but with so few stars showing in the sky I couldn’t figure out how to get there. I finally had to start at the other end of the Eagle, with Altair, and hop down the bright stars of the backbone. I got to the right spot, and couldn’t see a thing in the low power eyepiece. I had to boost the magnification to 120x to darken the sky sufficiently to pick up the dim outlines of the cluster, finally bagging it at 5:44. And that was it.


I am pretty certain now that M55, M75, and M15 were too far down to be possible. I still think that M54, M69, and M70 might have been possible at the base of the teapot, but by the time I got to them they were history. I missed M26 and later realized that I’d passed by M23 in my Sagittarius blitz.

I ended the night with 98 objects. I got M74, M109, and M98 in the scope only, M33 in the binoculars only, and the other 94 with both instruments. I also wrote down a one-line description of each object. As stated above, marathon observations don’t count for the Messier Club, but it was still useful to scribble down a brief description. It will make re-observing the objects easier and more interesting, since I’ll be able to compare my thoughts from a more leisurely look to my brief impressions on marathon night. And it is nice to have a physical memento of the night; I’ve reread my notes a couple of times already and have a feeling that I’ll return to them a lot in the future.

On one hand, I am frustrated that I ran out of time. M23 and M26 should have been easy prey–they were way up in the sky compared to some of the other home-stretch targets–I just never got to them. A rookie mistake, fairly small in the big scheme of things, but it kept me from that magical three-digit number.

On the other hand, 98 objects is still a great score for my first marathon, especially an “off season” marathon in which fewer than 110 objects were possible to begin with. It was a huge confidence builder and a heck of a lot of fun. I learned a ton about what works and what to avoid. And I’ll definitely be back for more.


* The printable version of this chart is now on the “Messier Marathon tools” page on the sidebar, along with a streamlined checklist for marathon night and other goodies.

** It occurred to me after I wrote this that it might sound a little odd. On one hand, I have been singing the praises of the Year-Round Messier Marathon Field Guide, which includes both a search sequence and charts for each object. On the other hand, I used a free star map to figure out my sequence and the Pocket Sky Atlas for actual finding. So you may be wondering if I used the Field Guide from the field at all.

The answer is that frankly I didn’t use it that much. The Field Guide charts are great, especially for people who don’t have an all-sky atlas or who  are looking for one-stop shopping for the Messiers. But from working on the AL Binocular Deep Sky and Urban Observing lists this spring I’ve gotten used to using the trio of (1) an observing list, (2) the PSA, and (3) a logbook for taking notes. I have used the Field Guide once or twice in the field, but I’m so used to the PSA now that it just feels more reflexive to reach for that instead. And I knew that on marathon night I needed to use what worked best for me.

That said, I did use the Field Guide to find the one that I’d missed (M40), to double-check that I’d gotten everything in the Virgo-Coma clutter (even though I used the PSA for the actual slog), and to work out a couple of the twilight rush star-hops. The Field Guide was most important for giving me the inspiration and confidence to tackle a marathon in the first place, and I definitely wouldn’t have been without it  by my side. It’s a great book and I recommend it to anyone with an interest in deep sky observing.


Observing report: Between the clouds

February 9, 2010

We’ve been having lots of cloudy and rainy weather here in the LA basin, so when a clear night comes along I try to take full advantage. Last night was clear, so I grabbed my 15x70s and went out to see the clusters between Cassiopeia and Perseus.

I made a New Year’s resolution to get through the Messier list this year. Right after I started on that project, I found out that some people–including Jay Reynolds Freeman–had done the whole list with 50mm binoculars. I hadn’t ever taken on a binocular observing project, so I decided to do the AL Binocular Messier Club at the same time. Plus, I would have felt like a wuss knowing that people had done the list with 50mm bins and I hadn’t even tried with my 15x70s. 🙂

The first week of January was pretty clear here and I got through almost all of the Messier objects that can be easily seen from my suburban skies at convenient hours. No M76 or M78 yet, at least not with the binoculars (M78 did fall to my 6-inch Dob). It was enough to get me hooked on the challenge and pleasure of tracking down faint fuzzies with binoculars, so I decided to start the Deep Sky Binocular Club, too.

I started that club a few weeks ago with what western objects I could get, before they get too close to the sun, or more depressing yet, too far down into the LA light dome (I’m at the far eastern edge of LA county). Then I went on through Orion, Lepus, Puppis, Gemini, Auriga, Taurus, and so on. A couple of weeks ago I was looking at my tally and realized that I’d gotten so busy with the southern stretches of the winter Milky Way that I’d forgotten about the circumpolar constellations! Which is a shame, Cassiopeia was the first constellation I learned when I got into amateur astronomy in earnest, and was a frequent stop on my earliest observing runs. And the stretch from Cassiopeia to Perseus is huge for the Deep Sky Binocular Club, with about a quarter of the objects on the list. I didn’t realize that until I’d gotten through most of the rest of the evening sky and was wondering why my tally wasn’t higher. Then I “discovered” how crucial Cass and Perseus are.

Then it started raining. A LOT.

As I compose this, it is raining. But last night was clear so I went cluster-hunting. I live in a back house with a big open parking area between it and the front house. This affords a decent bowl from which to observe without too much interference from local lighting. I usually wear a dark hooded sweatshirt and pull the hood up over my face so only my eyes are showing. With patience and good dark adaptation I’ve seen some things that I would have thought impossible in these skies, including the M galaxies around Canes Venatici and the Crab Nebula.

I didn’t start off with the Cass clusters. I wanted another crack at M78, and while I was waiting for my eyes to settle into observing mode I swept up M42 and M43, M35, and the Auriga M clusters. All very pretty, but they didn’t help M78 appear out of the murk. Sometimes right after a rain the transparency is just shocking, but sometimes there are mixed clouds and haze that really put the hurt on the faint fuzzies. Last night was one of those nights. M78 will have to wait for darker skies (maybe this weekend).

So I switched over to Cassiopeia and its neighbors. I started with the Double Cluster, which I’d seen umpteen times before but never logged for the Deep Sky Bino Club. And I was off and running. Here are the rest of my notes for the evening:

Tr 2 – Two chains of faint stars intersect to form the shape of a flying wing. Delicately beautiful.

Stock 2 – Extremely large, vase-shaped assemblage of faint stars. IMHO, rivals Double Cluster in binoculars, although its appearance is very different.

Markarian 6 – Dense patch of light, no granularity, makes a nice contrast with nearby Mel 15.

Melotte 15 – Larger and sparser than nearby Mark 6, but with more bright stars. Reminds me of a hybrid of the Double Cluster clusters.

NGC 663 – Obvious and granular even in these skies, brighter than nearby NGCs and even M103.

Kemble’s Cascade – Lovely curving chain of stars of varying brightnesses, anchored by NGC 1502 on one end and a counter-curving arc of bright stars on the other. Bright stars plus cascade make extended S shape.

Stock 23 – Jumps right out even in the surrounding rich starfield. Dominated by four bright stars in a flattened kite shape.

Cr 463 – Large aggregation of faint stars, smaller and dimmer than Stock 2, in a nice trapezoidal asterism not far from the pole.

All of these bizarre designations are explained in the official AL Deep Sky Bino Club list, and all of the listed objects are easy to find in the Pocket Sky Atlas.

I’d also tried for NGCs 129, 436, 457, and 7789, but didn’t pick them up. I think it was partly sky conditions–Cass was getting down into the LA murk–and partly observer conditions. I usually refuse to give up on something unless I have really put in the effort, maybe half an hour of laying flat on my back with every surrounding glint of light blocked out and lots of searching with averted vision. But last night I was cold and tired, and didn’t spend more than 4 or 5 minutes on any one thing.

Still, I ended the night with 10 more objects knocked off the Deep Sky Bino Club. The clouds can do whatever they want today, I’ve got a little victory energy to run on.


Heavens Above

February 6, 2010

Here’s one of those “How did I not blog about this sooner!?” things: 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?


January 29th full moon

February 4, 2010

Continuing our all full moon, all the time coverage here at 10 Minute Astronomy, here’s my best full moon photo to date:

You’d think that getting a decent picture of the full moon would be a cinch; after all, it comes around every month. The trouble is, there is a fairly narrow window in which the moon is precisely full (i.e., completely lit from edge to edge), and a couple of days on either side in which it is not-exactly-full-but-close. NEFBC moons look pretty to the naked eye but photographically they elicit pity mingled with contempt: “Ah, I see that you were trying for the full moon there. Bummer, dude.” Most of my previous full moon shots have fallen into that latter category.

The evening of January 29th was just about perfect. For one, the moon reached its fullest when it was centered right over western North America, dead in my sights. It doesn’t matter how still the atmosphere or how good your camera, if the moon maxes out while it’s over Sri Lanka but you’re in California, it’ll be in NEFBC territory by the time it gets to you (or, more accurately, by the time you get to it).

Also, the atmosphere was nice and still. It definitely helped that I was shooting in the middle of the night. When the moon (or anything else) is at its highest point in the sky, you look through the thinnest skin of atmosphere to see it, so there’s less opportunity for bad seeing to spoil the view. Also, by midnight the ground, buildings, roads, and so on have had lots of time to give up their daytime heat, so there’s less stirring of the atmospheric pot.

Also, I cheated, a bit. This is the raw image that came out of the camera:

To get the one at top, I did some fiddling in GIMP (still awesome, still free). First, a light application of Unsharp Mask to punch up the fine details. Be very careful about overusing this one, it is easy to do and oversharpened pictures look worse than raw ones. The biggest giveaway is artificial brightening of any high-contrast boundaries, which in the case of the moon and planets means a ring around the edge. Second, I converted the image from color to grayscale, which keeps the colored pixels from getting tweaked into grossness by the next step. Finally and most importantly, I used Curves to adjust the colors. Curves is sort of like Brightness and Contrast on steroids; you can hold some values constant and brighten or darken other selectively. It is hands down my most used image processing tool.

Feel free to download GIMP and the raw file above and play around. Better yet, get your point-and-shoot camera and binoculars or telescope and take your own moon photos to mess with. If you haven’t seen Mars, it’s not too late, but now that we’re past opposition it’s a little farther away and a smidgen smaller every night. So don’t tarry.