Archive for the ‘AL Lunar Club’ Category


The moon in 3D!

January 27, 2010

Last month I sent in my completed logbook for the AL Lunar Club to Steve Nathan, the coordinator for that club. We struck up a conversation and he shared the above image and some information about it (with permission to post):

The Moon image is attributed to L. M. Rutherford.  The images were take on Sept. 15 and Nov. 13, 1864.  His original negatives were copied by many (!) 3D stereo card publishers for decades…into the early 1900’s.  Other phases of the Moon were also shot in 3D, but all took advantage of the libration effect. Similar 3D images exist for the planets, sunspots, meteors, etc.; all with limited, to no 3D effect. However, somewhere around here I have Neil Armstrong’s famous lunar bootprint…in 3D! (FYI: much of the NASA lunar program photography was done in 3D).  Intriguing, eh?!

If you don’t have a stereo-viewer (I don’t), don’t click on the image (leave it at column width), hold your head back at least a foot and a half from the screen (farther is easier), cross your eyes until the moons double up and then merge the two in the middle to make one bright 3D moon between the two flat ones.

Earlier I had asked if two cameras had to be widely separated geographically to get the stereopair. For making stereopairs of Earthly objects, two photos must be taken with the camera in slightly different places to simulate the separation between our eyes. Since the moon is a quarter of a million miles away, it seemed logical that you’d need the cameras to be as far apart as possible. But as you can read above, the two shots were separated not in space but in time. Steve wrote:

Libration alone will do the trick, the object of interest (the Moon) presents two different views of itself to the observer; increasing the baseline/camera separation would be redundant.

Libration is the “wobbling” of the moon over time as seen from Earth, because of the complex geometry of the Earth/Moon/Sun system. Go here for a more complete explanation.

Pretty darned cool; there is absolutely no reason I couldn’t give this a whirl as soon as the clouds clear out. If I get anything, I’ll post it here. In the meantime, here’s another version of the stereopair that I cleaned up a bit in GIMP. I like the sepia-toned classic version as well; use whichever tickles your fancy.

Finally, many thanks to Steve for sharing the image and the information!


Moon bling

January 14, 2010

As I related in an earlier post, on Thursday, Dec. 17, I made my final observation for the Astronomical League’s Lunar Club. I e-mailed in my completed observation log a couple of days later. Yesterday my loot came in the mail: a certificate and pin.

I felt a sense of accomplishment (and, in the spirit of full disclosure, relief) on the evening that I made my final observation, and it was nice to send off my log, but there’s something extra special about getting the official certificate and pin. You know why they give these things out? I think it’s for the same reason that judges wear black robes and baseball fans doff their caps for the national anthem. We are a symbolic species, and on some subconscious level that stuff works, whether we want it to or not.

The certificate is going on the wall over my astronomy bookshelf, and the pin is going on the Kepler mission cap I got at the JPL gift shop last week (I still need to blog about the JPL tour–so much to do!). There are many like them…but these are mine!

And I want more. I’ve been plugging away at the target lists for the Messier Club and Galileo Club, and tonight is the start of a new lunar cycle so in a couple of nights I can get back to my observations for the Lunar II club.

Good luck with your own observations. If you’re not doing a formal observing program, give it some thought, working through one is challenging, rewarding, and fun. The complete list of AL observing clubs is here, and there are lots of other observing programs out there in books, magazines, and on the web.

More missions coming soon!


Mission 14: Three Astronomical Treats for Naked Eyes, Binoculars, and Telescopes

December 21, 2009

Mission Objectives: Bright Stars, Constellation, Open Cluster, Nebula

Equipment: Free star map, Naked eye, Binoculars, Telescope

Required Time: 10 minutes

Related Missions: Cassiopeia and the Double Cluster

Introduction: I’m in Oklahoma for the holidays. My best observation here so far didn’t require any optical aid at all. Remember last month when I was skunked in my quest to view the young crescent moon within 40 hours of new? On Thursday, December 17, the night after I got into town, I saw the 38-hour-old crescent moon in the western twilight over Oklahoma City, thus fulfilling the last requirement I had left for the Astronomical League‘s Lunar Club. I e-mailed in my completed log sheets on Saturday.

Instead of bringing a little scope with me, I borrowed back the one I had loaned to my brother. It’s a Synta MC90, another 90mm Maksutov-Cassegrain, but unlike my other little Mak it’s a short focal length, widefield scope. I got it out last night to show my nieces the waxing crescent moon, Jupiter, and the Pleiades.

Instructions: Speaking of the Pleiades (M45), they’re one of the best astronomical treats for a clear winter evening. Finding them is easy: look to the east after dark, and find a little knot of stars that looks a bit like a cooking pan. This is not the Little Dipper, although you’d be surprised at how many people think so on first spotting it. If you have a hard time finding the Pleiades, look for the 3/M/W of Cassiopeia, head past the Double Cluster to Perseus, and follow the lower of the two sweeping lines of stars that make up that constellation; the cluster is just off the end of the line. The Pleiades are pretty to the naked eye and probably best in binoculars. All but the widest-field scopes will have a hard time putting the whole cluster in the eyepiece, and even if you manage it, it’s prettier if you can see the cluster as a cluster, with a little open space around it. So this is one of those times that–in my opinion–binoculars trump a telescope.

If you have found the Pleiades, drop straight down (east) to find a V-shaped association of stars. These are the Hyades, another open cluster, in the constellation Taurus. One leg of the V is anchored by a big red giant star, Aldebaran, whose color is obvious even to the naked eye. You can pan around the Hyades with a scope if you like, but the cluster is so big that it really demands binoculars; binos fall right into the sweet spot of putting a lot more stars in your eyes without overly narrowing the view or getting you lost.

From the Pleiades, on to the Hyades, and farther on east you come to Orion, the most magnificent constellation in the sky. Find the three bright stars in a line that form his belt, and then three dimmer stars in another line that form the sword hanging from the belt. The middle of the three stars in the sword is not a single star at all. Rather it is M42,  the Great Nebula in Orion, a vast cloud of gas and dust, dozens of light years across, which is illuminated by the bright young stars burning within.

M42 is what I call a total object: like the moon, it looks good no matter what you use to look at it, and the more you look, the better it gets. With the naked eye, the nebula it is a faintly fuzzy star at the heart of a striking and majestic constellation. With binoculars, you’ll see a bit of nebulosity set amidst the rich starfields of Orion’s sword. In a small telescope, the full glory of the nebula starts to unfold, with glowing streamers of gas and dust spread out like an eagle’s wings. The central star will split apart into a group of four, called the Trapezium. Pour on more aperture and magnification and the view just keeps getting better. If the skies are clear and steady you may pick up a couple more stars in the Trapezium, and the surrounding clouds of gas and dust will start to look like clouds, with delicate knots and swirls.

And on it goes. You are not going to exhaust M42, not in a lifetime of observing. People with telescopes that require large trailers for transport, who have seen M42 literally thousands of times in their observing careers, still gaze into the heart of the nebula for minutes and even hours at a time. The bigger the scope, the darker the skies, the longer you look, the more there is to see.

But, hey, don’t think that if you don’t have a monster scope it’s not worth looking. Remember, M42 is a total object; it looks good at any scale. If the thought of setting up a scope in the cold and dark does not appeal, at least pop outside for a five minute session with binoculars. Make it a present to yourself.

Happy holidays!


Al-most the-ere

November 15, 2009


Well, I did get out of bed this morning and catch the very, very old crescent moon. It was just a white sliver hanging in the sky below Venus, like the very edge of a cosmic thumbnail.

One more to go: the waxing crescent moon within 40 hours of new. Tomorrow night will be too soon, and Wednesday night will be too late, so if I’m going to finish the Lunar Club this month, Tuesday is my only hope. If there are clouds to the west, or if the vast stew of atmospheric sludge over LA is too dense, I’ll be thwarted.

Fingers firmly crossed.

Waning gibbous moon in 15x70s

The waning gibbous moon from a little over a week ago, photographed through my 15x70 binoculars.


Dawn patrol

November 14, 2009

Dawn patrol 2009-11-14

So I’m trying to finish up this Astronomical League observing club. Not the Galileo Club, although I am persevering with tracking Jupiter’s moons and all the rest. No, I’m talking about the Lunar Club, a list of 100 targets for the naked eye, binoculars, and telescopes.

I’ve been chipping away at it off and on for over a year, and I’ve been stuck on the last three targets for months. Ironically, it’s not tiny detailed features that are holding me up, but naked-eye views of the whole disk. The clincher isn’t size or distance, but time. Specifically, get-out-of-bed time. My last few targets are views of very thin crescent moons, mostly waning crescent moons that are only briefly visible before sunrise.

I’m a night-owl, not  a morning person. If I’m up at 5:00 AM, it’s usually because I stayed up, not because I got up. But this morning I dragged my carcass out of bed at that unholy hour to go out and see “the new moon in the old moon’s arms”. That enchanting term refers to the faint illumination of the moon’s disk lit by Earthlight, between the much brighter horns” of the crescent that are still lit directly by sunlight.

You’ll recall that near new moon, the moon is between the Earth and sun, and the far side is almost fully illuminated and the near side is almost fully in shadow. At one time or another you probably have seen a young crescent moon low in the western sky at sunset, with the entire disk visible. That’s the flip side, after new moon, “the old moon in the new moon’s arms”. The photo on the right side of my banner is a one-second exposure of this phenomenon, taken with my Nikon Coolpix 4500 and 6-inch reflector. It’s really striking how many features you can make out on the shadowed disk by the faint reflected Earthlight, especially with a telescope.

My last three Lunar Club observations are:

  • New Moon in Old Moon’s Arms (Within 72 hrs of new)
  • Crescent Moon, Waning (Within 48 hrs of new)
  • Crescent Moon, Waxing (Within 40 hrs of new)

There’s also one about seeing the old moon in the new moon’s arms within 72 hours of new, but you can see that any month without really trying so I knocked it off ages ago.

New moon is Monday at 11:14 AM PST, so the 72 hour window opened yesterday at 11:14 AM. This morning I saw the new moon in the old moon’s arms. Tomorrow morning–assuming I get out of bed and there aren’t any clouds–I will hopefully see the waning crescent within 48 hours of new. Then Tuesday evening I’ll have a chance to catch the waxing crescent within 40 hours of new, and thus complete the requirements for the Lunar Club.

C’mon, alarm clock!