Archive for May, 2011

h1

W00t!, W00t!, and Gaaaah!

May 15, 2011

No time for a real post, so here are a few things of note. Two good, one bad, as the title says.

W00t! #1: Want to have your mind blown? Check out this photographic sky survey “meant to reveal the entire night sky as if it rivaled the brightness of day.” Link.

W00t! #2: Want to see a star blow up? No a simulation, but a real-life supernova? You have two choices: be very patient, or use a telescope. The last 5 naked-eye supernovae in our galaxy were observed in the years 1006, 1054, 1181, 1572, and 1604, although supernova 1987a in the Large Magellanic Cloud, a satellite galaxy of the Milky Way, was also naked-eye visible. Anyway, the point is that if you want to see the light of an exploding star with your own eyes, the best place to observe from is the eyepiece of a telescope. It’s not uncommon for a supernova to briefly outshine its host galaxy–that fact is worth pondering for a moment–and there are literally thousands of galaxies within reach of amateur telescopes, so even a modest telescope will show you supernovae in other galaxies on a semi-regular basis. A good site for keeping track of potentially observable supernovae is this one, which lists them by their visual magnitude (you may also find this limiting magnitude chart and this calculator useful to determine which supernovae are within reach of your instrument).

I bring this up because right now supernova 2011by is at magnitude 12.5 and may get brighter still. It has already been sighted in a 6in telescope (according to a post on Cloudy Nights) and is theoretically observable with even a 3- or 4-inch instrument under very good skies. It’s in the galaxy NGC 3972, which you can find using Stellarium, Cartes du Ciel, or any of a number of other free programs. Right now isn’t the best time to see it, thanks to the nearly-full moon, but hopefully it will still be reasonably bright at new-moon time near the end of the month.

Gaaaah!: Sorry to end on a bummer. The state of California is planning to close 70 state parks for budgetary reasons, and the Salton Sea State Recreation Area is one of those on the chopping block (story here). The Salton Sea is one of my favorite spots for camping and stargazing, and I’m seriously bummed that they’re going to shut down the park. I don’t know who to write to in order to fight this, and even if I did, I doubt if enough people would write to make a difference. One reason I go to the Salton Sea is that it’s a really nice campground that is never empty but never overflowing, either. So it’s a bit of a catch-22: the low traffic that draws me there in the first place pretty well ensures that the park will have few advocates. And I’m not even sure if fighting this would be a good thing. I know that the state can’t afford to keep all of the parks open, and maybe it’s better to shut down a low-traffic place like the Salton Sea park and let the property rest undisturbed*, than to shut down a high-traffic place and drive those folks to the Salton Sea and thereby increase the human footprint. I’ll think about it some more, and look around and see if there is anything to be done. In the meantime, I’m just sad.

*Normally, I’d worry that this was Step 1 in some nefarious plan to sell the land for commercial development, but the Salton Sea is such a commercial black hole that I doubt if such a plan could be put into place even if someone strongly desired it, and there’s no evidence that anyone does. It’s a lonely spot, and that’s the point–I like to get out and enjoy the emptiness.

Advertisements
h1

Camping and stargazing with a child

May 13, 2011

This started out as a comment, in reply to a question from Saint Aardvark on what it’s like camping and stargazing with a 5-year-old along. It grew in the telling, so I’m making it a stand-alone post. If you have ideas, tips, or tricks for making time outdoors with children easier, please share them in the comments!

I started taking London with me to dark-sky sites last summer, when he was about five and a half. Between July and November we went to Owl Canyon, Joshua Tree Lake, Afton Canyon, and the All-Arizona Star Party, so we basically built out from nearby destinations to farther ones. The hardest part for him initially was the long drive. We always pack him a backpack full of books and magazines. I also have a couple of kid-friendly CDs in the car, and I keep a full-size pillow within his reach so he can lay his head down and take a nap while we’re driving.

Once we get to wherever we’re going, London is usually off exploring and looking for bones or cool rocks near our campsite. He is very good at staying withing line of sight and not wandering more than 100 feet or so from me. My first goals are always to get our camping area squared away first, whether we’re staying in a tent or just sleeping in the back of the vehicle, and then to get a fire going for dinner. It helps to arrive an hour or two before sunset; much earlier and we just end up getting sunburned and waiting for dark, and much later and it’s harder to set up in the fading light.

I can’t overstate how useful–nay, critical–it is that I can trust London to mind himself for 30-60 minutes while I get everything squared away. It really drives me nuts when people say how lucky we are that London is well-behaved. It’s true that he has a naturally gentle disposition, but dismissing his good behavior as luck devalues all of the work that we put into disciplining him, and more importantly, all the work that he puts into disciplining himself. It’s precisely because of the effort we all put into maintaining a civil household that we can enjoy ourselves so much when we’re out of the house; good behavior out in the wild is earned by practice at home. I don’t bring this up to be snooty or a tiger parent. I just can’t stand wimps who are too lazy or passive to discipline their kids. That’s a dereliction of parental responsibility and a huge disservice to the children, who will have to learn discipline later on, the hard way, at someone else’s expense. End of rant.

After dinner I make a comfy spot for London to watch for shooting stars and satellites. This might be the lounge chair, if I have it along, or maybe just a sleeping bag and pillow laid on top of a big piece of cardboard on the ground. Or my lap, in whatever seating is available. Usually he tells me when he is getting sleepy and I get him settled in his bed. If we’re sleeping in the back of the car, I make sure a window or door is open so I can hear him if he calls out. He never has yet, but I think the knowledge that he could call for me if he needed is a comfort. And I just don’t want the car sealed up with him inside, even in good weather. I always set up the telescope as close to the car or tent as I can, so I can keep an eye on him and he can know that I’m nearby.

I want London to enjoy these outings as much as I do. I grew up out in the country and the ready access to wide open, semi-wild spaces had a huge impact on me. It’s not really feasible for us to live in the country, so my substitute is to get London out into nature as often as possible, and to try to facilitate his enjoyment of it. Even on the hardcore stargazing trips, I try to make sure that his interests and desires get at least equal billing with my own. I don’t think that’s indulgent–I’d do the same for a camping companion of any age. In the early evening, he mainly wants to run off the cabin fever from the car ride, do a little solo exploring near camp, and look for interesting things on the ground. (I’ve taught him to recognize venomous spiders, scorpions, and snakes. He’s never found any out camping, but when he was four he correctly IDed a black widow spider that set up shop under one of our plant stands in the living room!) I usually grill hot dogs for dinner and then follow up with s’mores. That makes the fixing of dinner something he can help out with, which keeps him engaged and gives him a sense of accomplishment. After dinner, we look for shooting stars and satellites until he conks out. Then I get in a few hours of solo stargazing.

In the morning, we have breakfast and go for a hike. I’m usually running on 3-5 hours of sleep, so having some caffeine available is a must. For the hike, London gets to choose the route and duration (within reason); he’s on these trips to hike as much as I am to stargaze, and we’re both comfortable with the give-and-take involved. If your little one isn’t into hiking, you might see if there is another outdoor activity that they are interested in, that could be their recreational time the way that stargazing is yours. In talking about our hikes, London and I always call them “adventures” that we “brave explorers” go on, and I think putting things in those terms helped inspire him the first few times out. Now he’s so hooked on hiking I could call them “death crawls” and he’d still be eager to get out there.

One last enticement: on the way home, we stop at a restaurant for lunch, and London gets to choose where we stop. This almost always means McDonald’s, but I can live with it. We bring dinner and breakfast fixings with us, so lunch on the ride home is our only extraneous expense. And it gives London a little something to look forward to at the end of the trip, when everything is over but the ride home.

Ultimately, camping with London is so smooth and enjoyable that it’s often the first choice for both of us for passing a weekend with good weather. It’s cheap, too: hot dogs, s’mores fixings, lunch at a fast food joint and 2/3 of a tank of gas usually add up to less money than we’d have spent over the weekend anyway. And it gets us out of the house and at least into some contact with nature. I hope he grows to love wild places as much as I do; I think the best way to cultivate that love is to help him enjoy his time in nature right now. I hope your own family outings are successful, and even when they’re not, I hope that doesn’t stop you from going. It’s worth it.

h1

Observing Report: Messier Marathon at the Salton Sea

May 11, 2011

Okay, clearly I am a little obsessed with Messier marathons. Last spring I got 98 of the 110 Messiers in my first marathon. Last month Andy and I only got 80, but that’s because we got clouded out for the nearly 30 predawn Messiers. I had planned to hang up my spurs and wait until next spring to try again, but I just had to have one more go. I really wanted to crack into triple digits, and checking Stellarium I saw that late April was not a bad time for marathoning, with at least 105 of the Messiers potentially visible. So on Friday, April 29, London and I headed down to the Salton Sea for another go.

Evening Rush

It was a much more relaxing start than my beginning-of-April marathon. That evening, I had been running around for about an hour trying to snag a bunch of fuzzies before they dipped below the horizon. This time I knew that some of the objects were just flatly impossible, and they tended to be the faint galaxies that one sweats over in a spring marathon: M33, M74, and M77. M79, the little glob in Lepus, was also out of the running. The only ones that were particularly timely were the nebulae in Orion (M42, M43, M78) and Taurus (M1). I started about 8:20 and in half an hour I had bagged all of the Messiers west of Leo–17 in total–so I could take a nice long break. I set out a lounge chair, London climbed up in my lap, and we spent an hour looking for satellites (we found 3) and shooting stars (9). Then I got him settled in his sleeping bag, had a snack and a big drink of water, and got started on the springtime galaxies.

Methods

I should break here and mention what tools I was using. For speed and ease of use, I made most of the observations with a 15×70 binocular (this one, in fact). Under dark skies, binos that size can reel in most of the Messiers without breaking a sweat, and the point-and-shoot simplicity and lack of stuff to fiddle with really makes the instrument disappear. For backup, and for hunting down some interesting non-Messiers, I had along the XT10. For finding, the Pocket Sky Atlas. To keep track of what I had seen, I used a one-page checklist and a map (both available here), noting the time of each observation and the instrument used (B or T) on the checklist and crossing out each object on the map.

Realm of the Galaxies

The Leo galaxies were a cinch, and I started in on the Virgo-Coma “clutter” at 10:36. Depending on how you draw the boundaries, there are at least 13 galaxies in this small patch of sky, and maybe more. I tend to count M49 and M61 in addition to the core 13 since they’re the next closest targets and also galaxies. I had never made it through the clutter with binos alone. Last year I got all of them but one with both binos and scope, but this time I really wanted to sweep the whole area without using the scope at all. And I did, although M91 and M98 were both devilishly hard. I had to pull my hood up around my face to block peripheral light and use averted vision to get them, but they were definitely there. M91 was my last object in this part of the sky, at 10:52. During my last marathon, the Realm of the Galaxies took an hour and a half. Last time out, I got through in what felt like a blistering 23 minutes, using a 5-inch reflector. This time I dropped my aperture considerably and still got through faster, in only 16 minutes.

(Before anyone chides me for not taking time to “appreciate” each beautiful and unique cosmic snowflake: I know, I know. This has been the perennial criticism of astronomical marathons. And here’s the perennial response: I have the other 364 nights of the year to savor every detail. The marathon is, explicitly, a race. Getting through 15 galaxies in 16 minutes is a personal achievement in celestial orienteering, not visual study. It means that next time out I’ll spend less time finding NGC Umptysquat and more time looking.)

To the Edge of Forever

One of the benefits of doing a “late season” marathon is that so much more stuff is up in the eastern sky. After getting through the Virgo-Coma galaxies I swept through all of the goodies in Ursa Major and Canes Venatici, the globs in Ophiuchus, and the northern reaches of the summer Milky Way. By a quarter after midnight I had 72 objects logged. Sagittarius was just starting to crawl over the eastern horizon and its Messiers wouldn’t be clear of the near-horizon murk for a while, and I had other things to try for. I wanted to see some quasars.

Er, say what now?

Yes, believe it or not, several quasars–the fiery hearts of long ago, far-off galaxies–are within reach of small-to-middlin’ amateur telescopes. Quasars were mysterious for decades, appearing as star-like points of light with highly redshifted spectra and usually massive output in the radio portion of the electromagnetic spectrum. They are now understood to be caused by energy emitted from the accretion disks that form around the supermassive black holes at the centers of most galaxies. As matter spirals into the accretion disk, there is tremendous friction. Imagine rubbing your palms together…at relativistic velocities! Friction in the accretion disk heats it to unimaginable temperatures, and that heat is radiated away as light and other electromagnetic waves.

The brightest quasar as seen from Earth is 3C 273 in Virgo. From a distance of 33 light years, it would shine as brightly as the sun in our skies. A planet in the core of the host galaxy would have at least two “suns”: the star around which it orbits, and the quasar shining equally brightly in the sky. I don’t know if anyone would be around to see it–it seems quite likely that any planets close enough to see the quasar as a sun would be heavily irradiated by it.

I didn’t know any of this just a month ago, beyond having a nodding acquaintance with the nature of quasars. I assumed that they were simply well beyond the reach of my telescopes. But a couple of posts at the blog Washed-Out Astronomy set me straight: “3C 273: Quasars are Easy” and “A Fist Full of Quasars“. Definitely worth checking out!

The aforementioned 3C 273 in Virgo is the brightest and easiest quasar, shining at magnitude 12.8. It’s also quite impressively distant, about 2.5 billion light years away. So the light from this quasar is more than half as old as the Earth itself; when these photons started their journey, our planet’s most advanced life-forms, bacteria, were still working up to producing an oxygen atmosphere, a task they would not complete for another 800 million years. Markarian 421 in Ursa Major and Markarian 501 in Hercules are magnitude 13.2 and 13.9, respectively, but they are much closer at 400 million and 500 million light years, respectively (why, our fishy ancestors had already evolved backbones by then!). Among the easy quasars, OJ 287 in Cancer is the most distant at 3.5 billion light years, but still not punishingly faint at magnitude 14.2. Finder charts for all four of these quasars are available at the links above.

3C 273 was an easy catch, just below an M-shaped asterism of faint stars not far from Porrima (Gamma Virginis, one of the bright stars of Virgo). Markarian 421, in Ursa Major, was even easier to find, since it sits right off the shoulder of a bright, 6th magnitude star. I made both observations with the XT10, but the quasars would have been visible in much smaller scopes; even a 4” ought to show them clearly. OJ 287 had set by the time I switched from Messier-hunting to quasar-hunting, and I skipped Markarian 501 because the rising wind was visibly rocking my vehicle and throwing sand horizontally through the air. It was time to get back to Messiers.

The Home Stretch

The string of clusters and nebulae that comprise the “steam” from the teapot of Sagittarius were easy prey for the 15x70s; it took more time to correlate the sky view with the atlas and figure out which was which, than it did to find them. The little globs along the bottom of the teapot–M54, M69, and M70, were tougher, and required the telescope, as did the globs and other Messiers just cresting the eastern horizon. At 2:25 I logged the last visible Messier–M15, a very nice glob off the nose of Pegasus–secured the telescope against the very impressive wind howling through the campground, and crawled into the back of the Mazda for some rack. M15 was my 100th Messier of the evening, so I knew that I had at least made my proximate goal of getting into triple digits. But there would be more Messiers up before dawn, and naturally I wanted to see how many of them I could add to the tally. I set an alarm for 4:00 and sacked out.

Knowing that I already had 100 in the bag dulled my ambitions a bit, and I snoozed until 4:30. I was not anxious to get back out in the wind–it was cold and uncomfortable. But needs must when the devil drives, so I dragged my tail out of the vehicle, parked a folding chair right up against the lee side, and got back to work. M30, a glob in Capricorn, was dead easy, as were the Andromeda galaxy, M31, and its satellite galaxy M32. I tried and tried for M110, M31’s dimmer satellite, and a couple of times I suspected a faint glow at about the right place, but it wasn’t good enough to log for certain. I gave up at 4:47–the sun wasn’t going to be up for almost another hour, but the eastern sky was already bright enough to make further observations impossible. So I finished with a total of 103.

Two more that might just have been possible are the open cluster M34 and the planetary nebula M76. Actually, I’m dead certain that M76 would have been possible in the XT10, but I didn’t fancy opening the scope and letting the wind sand-blast the mirrors, so I let that one go. M34 is iffy–it was definitely over the horizon before sunrise, but not by much, and I have real doubts about its visibility, scope or no scope. If M34 was not possible, then there were 105 Messiers visible that night, of which I found and logged 103, missing only M76 and M110.

Of the 103, I logged one with naked eyes only (M44, the Beehive cluster, in Cancer), one with the 9×50 finder on the telescope (M54, a glob in Sagittarius), 12 with the scope only, and 89 with the binos (I did go back and re-observe 19 of those 89 with the scope as well, just because I had time and wanted to see them). Except M74 and M77, I saw all of the Messier objects during the month of April. Also, I believe that M74 is the only Messier that I’ve never observed with binoculars–I should rectify that in a couple of months when it’s up before dawn.

What’s next? I should probably get back to the Herschel 400 one of these days. But part of me is already looking forward to next spring, and my next shot at getting all 110 Messiers. Stay tuned.

h1

May 2011 Astro Calendar

May 5, 2011

Zoiks, a little late this month! Don’t miss the meteors, I saw quite a few already last weekend (April 30).

MOON PHASES

  • May 2 (Mon) 11:50 PM PDT / 6:50 UT (Tues) – New moon
  • May 10 (Tues) 1:32 PM PDT / 20:32 UT – First quarter moon
  • May 17 (Tues) 4:07 AM PDT / 11:07 UT – Full moon
  • May 24 (Tues) 11:51 AM PDT / 18:51 UT – Last quarter moon

MOON CONJUNCTIONS

  • May 13-14 (Fri-Sat), waxing gibbous moon passes Saturn (13th) and Spica (14th), but not particularly closely.

PLANET POSITIONS

  • Mercury waxing crescent to waxing gibbous in the morning sky, greatest western elongation May 7.
  • Venus waxing gibbous in the morning sky, following greatest western elongation on Jan 8.
  • Mars rises before dawn, but stays close to the horizon.
  • Jupiter rises before dawn, following conjunction with sun on April 6.
  • Saturn rises shortly after sunset, following opposition on April 3.
  • Uranus rises before dawn, in Pisces.
  • Neptune rises before dawn, in Aquarius.

PLANET CONJUNCTIONS

  • May 7-15, Mercury, Venus, and Jupiter within 5° of each other.
  • May 15-25, Mercury, Venus, and Mars within 5° of each other.

METEOR SHOWERS

  • May 6 (Fri) Eta Aquarid meteors. Active April 19-May 28. Predicted to be a very favorable year.