Tuesday, February 26, 2008

My moon map

UPDATE, March 23: As is so often the case, an initial effort that I thought was cool at the time now looks like crap. The base image I used above was the first picture of a full moon I ever took, and I didn't realize how lousy it was until I took a better one. Also, the Apollo landing sites are all off by about 50 miles because I was just sort of eyeballing them instead of really checking their precise locations. So now, thanks to a better photo and this awesome site, I present my updated moon map (below). Obviously there are a zillion things that could be labeled here but aren't; everything shown here can be seen by the sharp-eyed on a clear night with no optical equipment other than the Mark 1 eyeball. If you want more details, I strongly recommend Cherrington's Exploring the Moon Through Binoculars and Small Telescopes ($20) and Sky & Telescope's Field Map of the Moon ($10).

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Saturday, February 23, 2008

How to get started in amateur astronomy. Step 1: Get real

I've already described how my advent into amateur astronomy was delayed by 20 years by unrealistic expectations. In my case, the expectations were that astronomy requires a telescope and is necessarily expensive, neither of which is true. But I suspect that many people "take up" astronomy--in a very limited, hardware-oriented fashion*--and then drop it because of other expectations that are no more accurate. I have two such in mind, and I'll explain them both.

* By buying a telescope on impulse, or getting one as a present, and then finding it difficult and unrewarding to use. More on this in future installments, and at the end of this one.

The first unrealistic expectation is that stargazing will be effortless. It won't be. Some things are easy, but they're still not effortless. You can see the Galilean moons of Jupiter just by walking outside and looking through binoculars. Ditto the Andromeda Galaxy and the Double Cluster in Perseus, all of which are probably in most amateur astronomers' top ten. But even for the easy stuff, you have to know where--and when--to look. Other things are harder, and all the more rewarding because of the skill and effort that goes into their finding. So here's the first filter: if you're not willing to spend a few evenings learning the constellations, go do something else.

The obvious retort is that you don't have to know the constellations anymore, because computerized telescopes will find stuff for you. That's true, but computerized telescopes are not the push-button-go dreams that they are marketed to be. Most of them have to leveled and aligned, and maybe even pointed at a few known reference stars, before they'll show you stuff. Sounds fun, huh? And dig the irony: you have to know how to find stuff on your own to set up the computerized scope that is supposed to find stuff for you. I can see a way to save yourself a few hundred dollars...

Now, there are computerized telescopes that use GPS and don't have to be leveled and aligned. You really can just turn them on and rock out. They also start around two grand. If you'd rather spend that kind of money than learn your way around the sky, go nuts--just be aware that you're not in my target audience.

The second unrealistic expectation is that the views from your back yard will look like pictures in books and on the web. No backyard telescope is going to give you Hubble-like views, for at least two reasons. The first is that the gorgeous photos of the Orion nebula and the Messier galaxies are all long exposures. Cameras, whether they use film or CCDs, can build up brighter and more colorful pictures than can the human eye, no matter how big the telescope you're looking through. Color in particular suffers, because galaxies and nebulae simply don't have enough of it to register on your retinas. Colorful stars, like red Betelgeuse and blue Rigel, both in Orion, are another matter, and they are among the most striking things in the sky whether you use a telescope, binoculars, or the good ole Mark 1 eyeball.

The other reason that your views will not look like the pictures you've seen is that the telescopes used by professional astronomers and the most advanced amateurs are almost always fantastically large and expensive compared to whatever you'll be looking through. A good starter telescope probably has an aperture between 2.4 and 6 inches (60-150 mm), whereas Rob Gendler takes most of his pictures with 12.5 and 20 inch Ritchey-Chretein scopes (the 12.5" starts at $17K, not including mount, cameras, etc.). But don't despair. As Guy Consolmagno and Dan Davis wrote in Turn Left at Orion (p. 202):
Galileo discovered the four major moons of Jupiter (forever after called the "Galilean satellites" in his honor); he was the first to see the phases of Venus and the rings of Saturn; he saw nebulae and clusters through a telescope for the first time. In fact, a careful checking of his observations indicates that he even observed, and recorded, the position of Neptune almost 200 years before anyone realized it was a planet. He did all this with a 1" aperture telescope.

Charles Messier, who found the hundred deep sky objects in the catalog that bears his name, started out with a 7" reflector with metal mirrors so poor that, according to one account, it was not much better than a modern 3" telescope. His later instruments were, in fact, 3" refractors.
If you've never seen the Galilean moons or the rings of Saturn for yourself, it is hard to explain what a rush it is. I can download gigabytes of Saturn pictures from Voyager and Cassini, but none of them carries the same visceral impact as even the smallest, blurriest view of Saturn through my telescope. It's like the difference between looking at a mounted dinosaur skeleton on the other side of the rope, and holding a chunk of fossilized bone in your hand for the first time, even if it is small, busted, and ugly :-). And I know I'm not the only one who feels this way. Most of our houseguests get a peek at whatever is up, and so far every one of them has been blown away.

The pleasure and satisfaction of amateur astronomy do not come from APOD-worthy views or from instant gratification. Rather, they come from finding and seeing things for yourself, and the enjoyment of doing so is proportional to the effort invested. (In these ways, amateur astronomy is no different from any other human pursuit, be it painting or fixing toilets or building relationships.)

Finally, be patient. You can't learn the whole night sky in one go. It may be possible to run out and buy a telescope and be blasting through the skies by bedtime, but it's neither likely nor recommended. Craigslist, eBay, and attics and closets across the planet are home to thousands of impulse-buy telescopes, and most of them are not worth the paper their breathless ads were printed on (or the pixels they were splashed across). Don't buy a telescope. Not yet. If you're just starting out, you don't know what kind of telescope you'll want, you don't know what to point it at, and you probably don't even know if you enjoy observing. The sky will be there for the rest of your life and far beyond, and there will be no shortage of telescopes around when and if you decide to buy one. But there are some things you need to know first, and that's where I'll pick up next time.


Thursday, February 21, 2008


The Navy set a new record for the most powerful railgun shot, and brought my dream of cosmically powerful weaponry one step closer to reality.

From the story:
Thursday’s test produced a record 10.86 megajoules, which sent the 7-pound aluminum slug at Mach 7 (more than 5,000 mph) for 80 meters, a roughly 20-millisecond ride.


Check out the visible shock wave. That's what you get at almost 1.4 miles per second.


According to the story, the shot trap was a steel box filled with 2.5 tons of sand, and after the projectile hit it, it was splayed open like a flower. I wish we had some pictures of that, instead of this stupid billboard getting blown to hell and gone. Ah well.

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The end of the eclipse

I wanted to take a series of photos like this for the entire eclipse, but two things stood in my way. The first was crappy seeing. If you look at the photos in the last post, they're not fuzzy because the scope was out of focus or the camera wasn't doing it's job. The atmosphere was just yucky. The Central Valley of California has about the worst air pollution of any non-metro area in the US, and the rising moon was swimming up through a roiling stew of hot air and groady particulates. By the time the moon was coming out of totality, it was high enough in the sky to be out of the real murk, but there was still quite a bit of turbulence.

The other limitation is the fact that I was just holding the camera up to the eyepiece. I could have gotten out the tripod and mounted the camera at the eyepiece, but I was lazy. As the moon got dimmer, exposure times got longer and pictures got fuzzier. I threw away literally hundreds. Still, I got a few keepers and I had a good time, and that's about all you can ask of a transient celestial event.

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Wednesday, February 20, 2008

Live blogging the eclipse

I'm coming to you live from mid-totality. I'm in here showing off instead of out there taking more pictures because I needed to recharge my battery. But don't worry, my sojourn here is very temporary.

Looking east from my back porch.

This is pushing the limit of how long I can hold the camera to the eyepiece without losing all resolution.

Hope you're not missing it, but if you are, I'll have more pictures soon.

Clear skies!

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Monday, February 18, 2008

How to get started in amateur astronomy. Step 0: Don't not do it

When I was 12, a friend brought a telescope catalog to school. It was from Celestron. It was the first time I'd ever heard of a Schmidt-Cassegrain. I borrowed it, kept it for a couple of weeks, read it cover to cover until I had large swaths of it memorized. I was hooked.

I was also broke. I computed that if I saved my allowance for two years I could buy the cheapest model in the catalog. I was 12, for cryin' out loud--my interests changed monthly. Saving up for a few weeks to buy The Dinosaur Heresies was about the limit of my financial stamina.

So what happened?



I returned the catalog. Pretty soon I was back to watching my turtles, reading about dinosaurs or whales or fighter jets, building Lego space cruisers, and listening to Dr. Demento. Life went on.

Astronomy became my dream deferred. I watched every shuttle launch I could, pored over magazine articles on the Voyager flybys and the debut and re-debut of the Hubble space telescope, eventually collected a giant folder of astrophotos for my screensaver, and put APOD at the top of my link list. I even took an astronomy course in high school and saw Jupiter and its moons for the first time through my teacher's telescope. But I never got my own telescope, and I never went out stargazing.

Twenty years passed.

Then last fall I took a trip to the Lick Observatory and picked up an intro astronomy book in the gift shop. Power keg, match, WHOOMP! A few days later I went out and found the moons of Jupiter, which I'd not seen with my own eyes for half of my life. A few weeks later I bought a telescope, and a couple of months later I built one.

I know what went right the second time, and you probably know some of it. But what went wrong the first time?

I didn't participate in amateur astronomy for two decades because I got two ideas fixed in my head when I was 12. Both of them were wrong, and I don't blame the folks at Celestron for either of them.

The first Bad Idea is that If you want to be an amateur astronomer, first you have to buy a telescope. Wrong, wrong, wrong. In the outline I have sketched out for this series of posts, buying a telescope comes somewhere around Step 5 or later, and it's an optional step anyway. Stay tuned, I'll tell you why.

The second Bad Idea is that Amateur astronomy is expensive. Nope. It can be expensive, certainly. In fact, you'll probably be flabbergasted by the money that some folks spend on gear. But you can get a good start for under ten bucks and for $25-30 you can stay busy literally for months seeing things that are invisible or nearly so to the naked eye.

So if you're interested in astronomy, you need not be intimidated. Chances are you already have the most useful piece of gear for the beginner. A few minutes' effort is all you'll need to see if you have a taste for stargazing--and if so, you can equip yourself to do almost everything for a lot less than you think.

Come on, give it a shot.


Monday, February 11, 2008

Total eclipse of the moon next week

There is going to be a total eclipse of the moon next week, on the evening of Wednesday, Feb. 20 for North American observers and early in the morning of Feb. 21st for Europeans. If you're in Hawaii, Asia, or Australia, I'm sorry, no eclipse for you (this time). Don't feel bad, you've been getting the good solar eclipses lately, and with them lots of astronomy tourism dollars (or rubles, or whatever). Don't believe me? Check this out.

It's the only total lunar eclipse this year and the last one until 2010. For North American observers is it conveniently timed, too, with totality lasting from 10-11 on the East Coast and 7-8 out here in Cali. Get the full details here.

If you've never seen a lunar eclipse, you owe it to yourself to pull out some lawn chairs and watch. You don't need any observing equipment at all, but you'll be amazed at how cool the moon looks through binoculars, even cheap ones. If you have a telescope, it won't hurt; you can pick your favorite lunar getaway spot and watch it slowly drown in darkness and then be reborn in light.

The picture at top was taken by me earlier tonight. It's not very good compared to some others I've taken, but I'm pretty happy with it given the circumstances of its birth. I took it through this thing, which I built myself:

More details at my Flickr site: scope and photo. And I gotta credit David Gilbank for the design, which I shamelessly ripped off.


Thursday, February 07, 2008

Dr. Vector visits the other Tethys

Usually when paleontologists talk about Tethys, they mean the ocean. Which is gone, or at least busted up pretty good. But tonight I explored the other Tethys for the first time, if "explored" is not too grand a word for sighting a wee dot of light at the edge of visibility at 125x in my telescope. Tethys is the fifth-largest of Saturn's 60-odd moons. It's about a thousand kilometers in diameter, slightly less than the distance between Berkeley and Salt Lake City on I-80 (a drive that figures prominently in John McPhee's Basin and Range and Assembling California, and in my own personal history).

I also saw Titan--biggest moon in the solar system, larger than the planet Mercury--and Iapetus. Dione and Rhea were too dim and too close to the planet to make out. (I don't know which moons those are in the photo above, I just liked it and didn't feel bad about ripping it from the horoscope site where Google Image Search found it.)

Actually I had no idea which moons I was seeing at the time; I sketched Saturn and the three I could see and did the IDing later, using Stellarium (still free, still awesome). Here's a screencap:

Seriously: if you haven't seen the rings of Saturn, or the moons of Jupiter, or the Orion Nebula, or the Double Cluster, with your own eyes, you owe it yourself to start figuring out how to make that happen. If you don't have a telescope, find a friend who does. Or buy one; Orion has some good 'uns for less than you think (my six-inch Dob*, which looks like a freakin' cannon, was under $300 nicely equipped). Or if you're not too far, invite yourself over and look through mine. The views don't suck.

* One of the ironies of amateur astronomy is that, thanks the success of even larger Dobs, a telescope four feet long, seven inches in diameter, and weighing 35 lbs is considered small.

Yes, it's true, you can Google up some Hubble images that will smoke anything you can see through a backyard telescope. Nothing wrong with that--I've got a big fat book on the shelf next to me with unreasonably gorgeous views of everything from the moon on out to the galaxy swarm in the Hubble Ultra Deep Field. But I promise you this: your first eyeball view of Saturn or Jupiter or whatever gem the scope is pointed at will sock you in the brainpan in a whole different way. Try it and see.

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Sunday, February 03, 2008

Dr Vector lives up to his name

As a vector, that is.

I suck at responding to memes. Darren gave me a Thinking Blogger award back around the Kazanian and Julia gave me another one in the mid-Aptian, and I haven't even publicly thanked them, let alone passed it on. So thanks, you two. You're both much better and more productive bloggers than me. Much love.

I'll pass that award on soon, I promise.

But in the meantime I'm going to leapfrog to a newer meme, for which I was also tagged by Julia, called the Writing Meme.

The rules:
  1. List 3 writing tips
  2. Tag 3 people whose writing style you admire
Julia wrote, "I want Matt's sauropod-paper-writing insights", so here goes:

1. Strive to produce not Least Publishable Units, but Most Publishable Units. Don't approach your manuscripts with the attitude, "What could I cut out of this to send somewhere else", but rather ask, "Is there anything else I could put in, either to give this paper more lasting value or because I know it's not worth writing up by itself and I may never get a better chance to say it?" Admittedly that's a tough row to hoe, and I feel like I only properly followed it once (in my Acta paper), but it's a noble goal.

2. In contrast to what I just said, if there is something short and sweet that you could knock out in one shot, don't make excuses and don't wait for the muses. Just go for it. I wrote the first draft of this paper in a single six-hour session. It's a shorty and, as before, it's my only example for this tip, but it felt great at the time and doesn't feel too bad now, either.

3. Write as informally as you think you can get away with (i.e., without sacrificing the science). Your papers will make better reading and more people will read them. There's a reason people still read The Origin for pleasure. Here's a simple heuristic: if reviewers aren't criticizing you for being informal, your prose is too stilted. Reviewers frequently knock me for being too informal, and that helps me find the balance. YMMV.

What the hell, I'm going for four. Memes mutate, right? This is the one that you're most likely to have heard before, but it bears repeating.

4. Play Frankenstein. Don't be married to the structure that you had in mind when you started writing. Feel free to move sentences around in paragraphs and paragraphs around in papers. And by "feel free" I really mean "steel yourself to the abhorrent thought of cutting up your beautiful rainbow children". Because they're not beautiful rainbow children. They're just words. And the sooner you Get Over It and learn to rearrange them in the order that best suits the goals of the paper (not your goals as a doting prose-parent), the better your writing will be.

And as long as I've broken the rules, I might as well go for broke. Here's the one you're least likely to have heard before, but it's something I feel strongly about.

5. Accept the fact that you are going to get things wrong. If you're not wrong at least occasionally, your science is boring (HT). You're not working close enough to the bleeding edge. There's a larger point here, too, which is that science only progresses by discovering new stuff, and that process inevitably means that some old stuff gets modified or reversed. As long as you are participating, that will be your fate at least once in a while. Don't be sloppy; don't invite error; but when it happens, don't kill yourself. I can't think of a single established scientist that I respect that hasn't been wrong about something. Admitting it and moving on is part of being a professional, and a grown-up.

My three tags are:

1. Brian Switek at Laelaps--I want to know how he writes so damn much all the time. It's embarrassing!

2. Mike Kaspari at Getting Things Done in Academia--He already writes a lot about writing, but in particular I'd like his thoughts on what makes for good collaborative writing.

3. Mike Taylor. His prose always seems to flow like water, and I'm not just buttering him up because he's my brother and co-blogger. Read his papers and see for yourself. He doesn't have a blog of his own, but maybe he'll co-opt an SV-POW! post to impart some wisdom (with the obligatory sauropod vert picture thrown in just to keep the letter of the law).

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The Evolutionary Pathway of Dr. Vector's Book Club

Evolutionary Pathways in Nature, by John C. Avise of UC Irvine, reads great on the crapper. The book is just under 300 pages long, and that's including a readable intro on phylogenetic character mapping (PCM), a glossary, references, and an index. The 200 pages of meat cover 67 examples of evolution, at about 3 pages per example. "Evolution of what?", you ask. Damn near everything. Magnetotaxis in bacteria. Bipedal hopping in kangaroos. Caterpillars that get ants to feed them their own larvae. Eusocial shrimp. Fish placentas. Cryptic elephant species. Poisonous birds. Parental care in land crabs. The origins of everything from HIV to Afrotheria.

Avise is a adroit writer. Three pages is not a lot of space in which to explain anything, but his descriptions of these biological mysteries and their elucidation by PCM are masterpieces of concision and tidiness. And he does not shrink from discussing the limitations and complications of the studies where they arise. Every example includes a tree with characters mapped on. I will keep this book close when I am writing my next paper, and hopefully turn out something a little more elegant.

If you're tired of seeing phylogenetic analyses that don't seem to tell us anything about, you know, critters and whatnot, or if you're tired of reading speculative wiffle with no phylogenetic grounding, or if you're just plain tired and can only muster five minutes of attention before you sack out at the end of the day, this is the book for you. Three pages is doable, by anybody, under just about any circumstances. If you can take more, go for it. I like the book as an evolutionary analogue of the 1001 Nights, with Avise standing in for Scheherazade, but there is more here than a big pile of short reads. Reading the stories--and they are stories, and therein lies much of their charm--is like watching the stars come out at night. The first one is a little gem, and so is the second, and third, and the fourth. But soon they add up to something that is vast, awesome, and humbling.

But also exhilarating. Like the night sky, the tree of life has the complementary virtues of being knowable--thus inviting exploration--and inexhaustible, so that we need not fear running out of marvels to wonder at. (Note that I am speaking here of the entire tree of life, not just the extant tips, which are all too exhaustible.)

The book's most glaring fault is that, like most Cambridge titles, it is reedonkulously expensive. Sixty-nine smackers for a small, slim paperback--almost half again as much as you'd pay for a new hardback copy of Gould's Structure of Evolutionary Theory, which is more than five times as long. The best defense I can offer is that Avise's writing is so engaging and expansive that the book seems much longer, and Gould is so baroquely verbose that when you read SET you'll long for death before the end (trust me, I read it twice).

So, Evolutionary Pathways is a little steep. That's what birthdays and holidays are for. Put it on your wishlist, and when it comes in, park it on your bedside table or in the bathroom magazine rack. It's chicken soup for the evolutionist's soul.

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