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View Full Version : A few nights at Kitt Peak



parejkoj
2008-Jun-08, 08:42 AM
Just a few notes from the 4 meter telescope at KPNO (http://www.noao.edu/kpno/)...

Up here with an advisor who is taking spectra of potential lensed quasars and/or quasar line-of-sight associations.

The wind on the hill to the 4m is phenomenal! Currently reported as >50 km/h just above the road I walked up. Our telescope tech is trimming the louvers to keep the 'scope from shaking too much.

And the sky is pretty nice too, though the haze layer is still around, so the seeing is only ~2".

I took my Canon A510 with, and took a few 15s exposures by setting it on the ground. Not the greatest astronomical camera in the world, but with the sky here as it is, it makes some decent images. The attached is a tweaked view of the 4m from the road between it and the visitor center, while I was on my way to get my "night lunch."

And there really is a piano near the bathrooms in the 4m dome. Guess one needs to have something else to do while data is downloading. Though considering how much faster things work now than they apparently did a few years ago, I suspect it doesn't get used much.

I'll write more tomorrow, perhaps, maybe with some more pictures from around the site.

Oh, and the data has been flowing quite well, after a few problems with the slit rotator earlier in the night.

parejkoj
2008-Jun-08, 09:41 AM
Note: apparently the pool table in the 4 meter is so tilted that whomever breaks will end up putting them all into the left corner pocket. I guess it doesn't get much use.

Apparently some observers used to live in the dome, which is why this stuff is here.

ngc3314
2008-Jun-08, 04:55 PM
Apparently some observers used to live in the dome, which is why this stuff is here.

True, and not quite as desperate as it sounds. On the second floor of the 4-meter building were several dorm rooms that were in regular use "back in the day" - with darkrooms in the building, sky survey prints likewise, and a long walk back to the other dorms at night's end, they were not a bad option. (I did that at least once - nice and quiet, too). As the typical numbers of observers on the mountain decreased and logistics costs went up, they went out of use. But the piano, full kitchen, plate-measuring rooms and (for a while) weight room stayed, in what was for over 15 years the tallest building in Pima County.

parejkoj
2008-Jun-09, 10:03 AM
First night went very well: got a few potential lenses, some binaries, and a whole lot of "just a line of sight association, go on to something interesting"s.

Didn't get a chance to explore the grounds very much during the day, since I had some trouble falling asleep. I guess I'm not as good at recovering from being up until 6am as I used to be.

Went up to the 2.1 meter to watch how the older equipment works. I need to learn, if I'm going to come and use it in the future, since one doesn't get a telescope operator with the 2.1m (one does with the others).

There were two people doing observations of cataclysmic variables (white dwarf/main sequence pairs, very short orbital periods and highly variable emission, typically showing emission lines from the white dwarf accretion disk). Shortly after I arrived, the autoguider conked-out. I didn't touch anything, I swear!

It turns out that the guider does this occasionally. They suspected it was due to some network link dropping out. Whatever went wrong, it takes ~20 minutes to reboot the whole system, so they decided to hand guide. Of course, when trying to observe a ~18th magnitude star with rather poor seeing, the monitor doesn't really show anything to hand guide on! 12th magnitude is a bit easier though... They had a long list of potential targets.

I must say, I was quite surprised at just how variable these cataclysmic variables are. We could see the emission line profiles change between each 7.5 minute exposure, and some lines would appear in one exposure, have strong central absorption in the next, vanish in the one after that, and re-appear later. Guess that's what you get with a star and a white dwarf+accretion disk stuffed into a region smaller than the size of our Sun...

parejkoj
2008-Jun-09, 11:24 AM
And now I'm back at the 4m. Walking here from the 2.1 I got an amazing view of the Milky Way. The wonders of high altitudes, dry air and especially no lights!

The final run of the planned targets went smoothly (not many binaries), so we moved on to an auxiliary list from a new photometric quasar identification scheme. So far, those have all been "What the heck is that?" Makes things more interesting when you have no idea what the spectra represent...

parejkoj
2008-Jun-11, 05:52 AM
Well, last night was pretty busy: I had to try and prioritize targets, based on whether they were X-ray sources by cross-matching the target list with previous data. Sadly, no prioritization was possible, since none of the targets had been observed with new instruments (Chandra or XMM-Newton), and none were found by ROSAT (a low resolution, shallow X-ray satellite from the 90s).

Oh-well... If only I could have my way, and get an all sky survey with something like Chandra down to 10^-14 erg/s or so... One can always dream!

Also watched part of the set up process at the 2.1 meter, by a graduate student who was observing asteroids. Take away lesson: I'm very glad my research involves things that move at the sidereal rate (galaxies and quasars), as calculating drift correction for things in our solar system looks quite complicated. If you get it wrong, the object will drift out of the slit, so you have to apply hand corrections every couple minutes... She'd been here before though, and was getting some good data.

As to the "what the heck is that" objects from our previous night? Took deeper spectra of a couple, and we still don't know what they are. A few more from the list turned out to be quasars (yay!), two are dim M stars, one is likely an elliptical galaxy at high redshift (maybe ~.9, though the spectrum was pretty ratty).

Tonight, longer exposures of more objects from the list. We shall see what surprises await.

And here are a few more views of the site: the 4 meter from the road in moonlight, and a view of the other telescopes from the 4 meter with vultures circling.

parejkoj
2008-Jun-11, 06:40 AM
Last night I got a chance to sneak a peak through the 20" they have in the visitor center (pictured below). I asked the docent very nicely in the afternoon, and he agreed to stay after the public observing time for a few minutes. In rapid succession, I saw M57 (the Ring Nebula), M8 (the Lagoon Nebula, which I'd never seen before!), M101 (a large spiral galaxy, whose arms were hard to see, even at this site), M51 (another spiral, and I could see the arms a bit more clearly than M101), and M64 (the Blackeye galaxy, so called because it has a dust lane running across one side making it look like Rocky after a fight).

It's a very slick setup, and if any of you are ever in the Tucson area, I highly recommend coming up for their Nightly Observing Program (http://www.noao.edu/outreach/nop/). The people attending were enjoying it, and it's been full every night. The program includes a tour of some of the big telescopes and the grounds, a guided tour of the sky and a look through the 20" at a bunch of pretty objects. It even includes dinner...

And speaking of education/outreach: while I was at the 4m this afternoon looking at data from the previous night, a group of high school teachers came in. They were here as part of the Research Based Science Education (http://www.noao.edu/education/arbse/) program, which includes a couple nights of time on one of the professional instruments! Another great outreach program from the NOAO. We brought them into the control room, and fielded some excellent questions about galaxies and quasars and the observations we were taking. A few of them came up to thank us during dinner; apparently, not all astronomers are good at, or enjoy answering questions, but I guess we did just fine. :)

parejkoj
2008-Jun-11, 09:02 AM
Tonight's menagerie has so far included a quasar pair where one member was so highly dust reddened that its colors (and spectrum) were completely different from the other member. I'm quite interested in that one, as it relates to my thesis work. Such pairs, where one member is mostly, but not entirely, blocked by dust, are fairly rare, if our understanding of quasar lifetimes is correct. Certainly, very few are known.

Another is a quasar/elliptical galaxy pair at z=0.38. The SDSS image looks like they may be sitting in a cluster, which makes sense. The physical distance at that redshift means they are probably not directly interacting, but the quasar emission is probably heating the gas in the cluster. Another one that might warrant a bit more study.

parejkoj
2008-Jun-11, 10:11 AM
Stepped outside briefly, to see if Andromeda was visible. It was, naked eye, as expected (not that I'm complaining!). The Milky Way was out in force again. And I saw M7 (large, bright open cluster towards the center of the galaxy), though I had to come in to identify it; I figured that smudge below the tip of Sagittarius might be an open cluster, but I'd never seen it before. Probably saw M8 naked eye as well, if I'd have known what I was looking at.

Only one problem, though: the wind is about 40 mph, nearly continuous. We were huddling around the dome to keep from blowing away. Didn't even attempt to put the camera on the ground for a picture: it would probably blow across the border!

AK
2008-Jun-13, 04:29 AM
I had an amazing time down there in 2006 myself. My favorite image, despite, or perhaps because of, the slight blur...

http://i66.photobucket.com/albums/h257/AeotheKaear/Arizona/DSCN0017.jpg

parejkoj
2008-Jun-13, 05:35 AM
Well, I'm home. Though arriving here was a bit of a mess: flight was cancelled, and we had to scurry to find a new way home. Arrived tired, but in good spirits.

Lessons learned:

1. The length of a summer observing run is not so hard to deal with (the useful observing time is only ~8pm to ~3:30am). Contrast this with a run in the winter when the night is longer... Which I'll probably have to deal with, if I get a successful application in for the September deadline.

2. Trying to post while data is coming in just means I end up even more confused about both post and data.

3. People who are willing to put up with my questions (I always have lots) are my bestest friends!

4. I should be working on my thesis, not posting on BAUT... Though one could substitute just about anything for that last part.

oh, and big telescopes are pretty darn cool!

parejkoj
2008-Jun-13, 05:37 AM
AK: where was that taken from? I can't figure out the perspective.

spaceboy0
2008-Jun-21, 01:40 AM
so when it's 110 degrees in Tucson what temperature would it be up at Kitt Peak? At night?

parejkoj
2008-Jun-21, 01:53 AM
Is that what it was in Tucson that weekend? During the day it was between warm and hot, but no humidity (here in Philly, even 27C can feel stifling), probably around 30 at the hottest, but cooling quickly in the afternoon. At night it got down to around 12C at the coolest.

In fact, you can check yourself (http://www-kpno.kpno.noao.edu/Info/Mtn_Weather/)!

But the high wind is what did me in when I was outside: even at 12C the windchill can really sap the warmth out of you.

spaceboy0
2008-Jun-21, 06:08 PM
are all the domes in the same area of the mountain?

what is the elevation at the dome level?

ngc3314
2008-Jun-21, 08:10 PM
The domes are all over the mountaintop, spread over about a mile - you can browse them at the Google Maps satellite overlay (http://maps.google.com/?ie=UTF8&ll=31.960683,-111.598091&spn=0.010468,0.013304&t=h&z=16). The altitude at the summit is about 6900 feet (2100 meters). That didn't bother me 20 years ago; these days I definitely notice.

spaceboy0
2008-Jun-21, 08:19 PM
If I'm staying in Tucson or Phoenix (I won't have a car), is there a Transportation service I can take to Kitt Peak?

ngc3314
2008-Jun-22, 01:14 AM
The observatory runs shuttles for staff and visiting observers. For ordinary tourist visits, I've heard of a few people enthusiastic enough to take a taxi the 40 miles or so each way from Tucson. Sounds expensive. Google turns up some commercial tour operators who operate tours of Kitt Peak, at least from Tucson (BTW, there is an airport shuttle service running between Phoenix and Tucson, or was the last time I needed one). Further poking around suggests that a few of these still run but not too regularly.

AK
2008-Jun-23, 05:23 AM
AK: where was that taken from? I can't figure out the perspective.

I can't remember offhand, it was two and a half years ago.

As for the temperature, if it's 110 in Tucson it will be hot up there during the day too. It cools off considerably at night, but even in January it was only actually cold on a single night. As it was mostly pleasant to chilly in the winter, I imagine summer nights are quite nice.