Feder Observatory

A Blog for Minnesota State University Moorhead's Paul P. Feder Observatory

Archive for May, 2013

Observing Log, 5/23/2013 0

Posted on May 24, 2013 by Matt

Nice clear night, though there is a nearly full moon and the amount of actual dark time is pretty short: about 4 hours.

I shot BVRI images of QQ Dra and EL Dra over a fairly short period of time, and then longer time series in R band for both stars. I tried a new observing strategy tonight since the two stars are fairly close to each other in the sky: 5 images of one, then 5 images of the other, then back to the first, and so on.

Both stars have data in the Catalina Sky Survey Data Release 2 that show interesting features.

The air temperature was approximately 62 degrees F, and the focus was set to 2855.

Observing Log, May 9, 2013 0

Posted on May 10, 2013 by Matt

Seeing was pretty good tonight, steady at 5-6 pixels FWHM. I observed EY UMa and Landolt standards in SA104 for the first half of the night (I *hope* I caught another maximum of EY UMa…that was the goal).

For the second half of the night I observed V0440 Lac.

All of the observations were done in R band. Some of the images I shot were early in the evening or late in the morning and the sky was pretty bright. Those images would be good for checking how well our dome flats do at flattening the sky (the spectrum of the sky at this time will be different than the dark sky but it is also quite a bit different than the spectrum of the light we use for the dome flats).

Matt Craig

Looking at Galaxies and Stumbling Upon Supernovae! 0

Posted on May 08, 2013 by Juan

Sometimes it is just fun to look at the sky.  On the evening of May 6-7, Beau, Nathan, and I looked at a couple of galaxies just to see what we could see in some deep exposures.  Hypothetically, I had two goals.

  1. I wanted science images to test Dr. Craig’s data reduction scripts on.  Up until now, Dr. Craig’s scripts for cleaning up the Feder data (e.g. – fixing the FITS headers, adding an astrometric solution, etc) had only been run by Dr. Craig.  So this was the test to see if they could run on my own computer.  We had a few problems, but all in all, his scripts cleaned up this data nicely.
  2. Secondly, I wanted to get an image of an edge-on galaxy to provide a comparison light profile to one that one of our students is working on with the much more face-on galaxy M101.  

A Edge-On Galaxy and a Surprise Guest!

For these reasons, I shot images in B, V, and R of M65.  The combined exposure time was 360 seconds in R, 360 seconds in V, and 900 seconds in B.  While I did reduce the data properly, removing bias and dark current and applying the flat-fielding corrections, this was my first attempt to merge such images into a single color image, so the fidelity of the color image may be a bit bogus.  In any case, here it is, a color composite image of M65 as shot at the Feder observatory on a night with mixed seeing.

M65 (Composite Color)(Click on Image for Full Resolution Version)

I really like how this image of M65 came out, especially how clear the dust lanes and spiral arms are.  Not as impressive as other people’s images of M65, but I was happy.  Unknown to me at the time, it turns out M65 had a supernova discovered in it on March 20, now designated Supernova SN2013an.  Zooming in, we can clearly see it…


A Much Fainter Galaxy with an Expected Visitor

Since we had to wait a little bit for M65 to rise high enough to be at a lower airmass, we took the opportunity to push the limits of the Feder 16-inch by taking images of the supernova candidate announced in the  Astronomer’s Telegram #5051.  This was the intended supernova image of the evening!  The Astronomers Telegram noted a “bright” supernova candidate in UGC 9379 which was at an airmass of 1.28 at the start of the night and getting better as the night went on.  This galaxy is relatively faint so we shot exposures adding up to 600 seconds in R, 900 seconds in V, and 1800 seconds in B.  Here is the resulting color composite image (again, I don’t trust the color fidelity):

UGC9379 with SN Candidate (Composite Color)(Click on Image for Full Resolution Version)

During that 10 minutes of exposures in the R band, a satellite flew through the field of view, thus the streak on the left side of the image.  

The galaxy UGC 9379 was very clearly visible in the R and V bandpass images, but was just barely visible in the B bandpass, despite the long exposure.  That said, the supernova was quite visible in all bandpasses and possibly most distinct in the B bandpass.  This color difference between the galaxy and the supernova is quite visible in this color composite image.

So there you have it, we intended to look at one supernova and two galaxies, and we got a second supernova as well!

Observing Log: May 6-7, 2013 0

Posted on May 07, 2013 by Juan

This was my first night in a while starting up the observatory all by my lonesome
  • Had a small hiccup at startup with MaximDL not connecting to the camera, I went ahead and unplugged the yellow ethernet from the USB extender in the back of the control room computer and reconnected it, then MaximDL connected.
  • Targeting was confirmed with alpha Lyn.  Only a small adjustment (1/5 of a frame width) required to get alpha Lyn centered again.
  • Shooting twilight flats by turning off tracking and leaving the telescope pointed at a single point in the sky (near where Vega was at 9:10 PM CDT), may not be completely uniformly lit.
    • Used 10 sec exposures in R (10 exposures)
    • Used 30 sec exposures in V (10 exposures)
    • Used 30 sec exposures in B (10 exposures)
    • I suspect the last few twilight flats may have been too underexposed.
Beau and Nathan arrived around 9:30 pm.  Once Matt reminded me (viaiMessage) to toggle the Auto Dome switch, dome tracking started and we could see on a 5th magnitude star for focusing.
  • Air temp is 62˚F at start of night which implies a focus setting of 2838.  Focus was set to 2812.  
  • When at 2838 focus, FWHM was bouncing around a lot (up to 20, as low as 6.5, bouncing around 7-9 FWHM)
  • At 2855 we had decent FWHM down to 3-7 range.
Once focusing was completed, I reviewed the  Astronomer’s Telegram website and discovered Telegram 5051 which announced a likely “bright” supernova in UGC 9379 which is at an airmass of 1.28 at the start of the night and getting better as the night goes one.  This galaxy is relatively faint so we shot 5 exposures each of 120 sec at R, 180 sec at V, and 10 exposures at 180 sec at B.
We also looked at edge-on galaxy M65.  Shot 3 exposures each 120 sec at R and 180 sec at V,  and 5 exposures at 180 sec at B.
We closed out the night by obtaining biases and darks.  Beau and Nathan closed up shop around 1am.

↑ Top