This page is for the

"Spitzer AGN" group from the National Optical Astronomy Observatory's Spitzer Teacher program.

We have submitted a proposal to use the Spitzer infrared space telescope to observe active galactic nuclei. Our first observation has been scheduled. Ground based observers are invited to participate.

Links

Spitzer AGN Blog
Post your messages here. Articles and links to other projects may be posted here.

Downloading Spitzer data with Leopard. Using our data set as an example.

Observing FAQ 2
Coordinates, exposures, links and questions about how to observe our new target.

Guide to Differential Photometry
For students of Jeff Adkins, a guide to reducing images to data for projects.

Spitzer AGN overview page
Hosted by Spitzer Science Center

NOAO

TLRBSE
Spitzer page

SPITZER

Spitzer Teachers Program Page

Home
Cool Cosmos
Tools page (Pride)
Archive/Analysis

GLAST

E/PO Home
AGN/Polar target list
GTN Home

NASA ADS (document searches)

ESPACE Academy Projects

AstronomyTeacher.com

Participants

Jeff Adkins

Home Page
Email

Linda Stefaniak
Steve Rapp

Acknowledgements

We gratefully acknowledge assistance on this project from

TLRBSE

The Spitzer Space Telescope Science Center

Dr. Mark Lacy, Spitzer Science Center

Dr. Gordon Spear (GTN telescope network)

Dr. Phil Plait, Sonoma State University

Archival

Observing FAQ 1
Coordinates, exposures, links and questions about how to observe 4C 29.45.

Round 1 Results
This page contains the archive from our first observation using Spitzer, including science posters.

 

 

Round 2 Observing Tips

The round 2 Spitzer MIPS observation has been scheduled for April 8 2006 at 10:38 UTC, which is 3:38 AM Pacific Daylight Time.

The best filters to use are V,R,I from a standard UVBRI set. If all you have are LRGB filters, we're interested in L and R for related student projects. We're interested in L data on any observation at any time for time-based observations.

In the past, we suggested that we need your images to be calibrated with darks and flats as necessary to reduce noise and make the pictures photometrically useful. If you can do this, we prefer it; however it may be that our data analysis process makes the darks and flats irrelevant. We are investigating this. For volunteer observers this means we'll take anything we can get!

Good luck everyone! We'll be in touch next week with everyone on the mailing list about transmitting your data to us.

Observing FAQ

1. What are the coordinates of the new target?

Information about GTN 3 from the GTN Program web site.

2. Where can I get a finder chart?

Go this page http://gtn.sonoma.edu/participants/catalog/

and click on the button for GTN 3. Finder charts and magnitudes of calibration stars are posted. On the home page for this project you can see a sample picture and a low-rez finder chart.

3. How long an exposure do I need?

We have used a 1 to 2 minute exposure on a CCD camera attached to a 14" telescope and gotten useful data. Longer exposures may be needed for filtered observations. If you can see it in the image, we can probably use it.

4. Where do I send the files?

You can send the files to me, Jeff Adkins, at astronomyteacher"at"mac.com. If you have many megabytes of data you can either send me a CD or arrange to upload them to my public .Mac folder (should work for Mac and PC). Contact me for details.

5. What format should the files be in?

16 bit unsigned FITS is best for us, although we can read 16 bit signed if necessary. JPG, GIF, BMP, etc, and other common file formats do not contain the astronomical data we require.

6. Do you need our longitude and latitude?

No, since we are doing differential photometry compared to nearby standards, we do not need to know the airmass or other details that depend on your position. We do need to know the date and time of the observation, plus your time zone if you do not report the time in UT.

7. What is a "calibrated image?"

Explaining how to make a calibrated image is beyond the scope of this site. The images need to have had dark, flat, and bias frames applied so they are photometrically useful. This essentially reduces noise from the image due to sky brightness, instrumental signals which do not correspond to light, and heat in the camea. Your camera manual should explain how to do this. We have some evidence that it may not matter if our pictures are calibrated as our mathematical models used to determine magnitudes from brightness counts may compensate for this.

8. Should I shoot the target with IR blocked clear or non_IR blocked clear?  I have both.

Non_IR blocked clear.
 
9. What filters are need for the exposures?

We have calibration stars for V,B,R, and I. Therefore all are useful. You'll note some of the magnitudes get down as far as 17 in U, so getting those will be more challenging than in the other bands. The finder charts and calibration data is on the GTN program web site (see link at left, click on #7.) Smaller telescopes may not be able to pick up some filters.
 
10. Does it matter if the chip is binned or not?

(Binning is a way of combining pixels when offloading the image from the chip so that fewer numbers are needed, speeding image download time and reducing file size.) Since we are not interested in position data, the target is starlike and not extended and the resolution of the target serves only to identify it, I would say it does not matter. Some of the stars we use to positively identify the target on the finder chart are even dimmer than it is, and might be lost in coarse binning. If you can positively identify it off of the finder, I would say not.

11. When should I take pictures?

Before, during and after the Spitzer observation. There will be two Spitzer observations of our target. The first one has been scheduled for April 8, 2006, 10:38 UTC. The observation will take about 20 minutes on the Spitzer, so that is when you should attempt to observe it.

Any observations you make before or after will be used to track change over time to make sure the target is not intrinsically changing. If it is experiencing a burst, we will hopefully be able to adjust our observations using the time-based data.

12. What size in arcminutes should the image be?

The finder chart is 10 x 10 arcmin. If yours is larger that's OK. If smaller, there may not be any standard stars in the image. You have only two options in that case. Move the telescope to the standards and take an identical exposure, or use the standards to find the magnitudes of stars closer to the target.

13. How do we reduce the data to a light curve?

The Spitzer data will need to be analyzed in a different way than the CCD images we are seeking. We have constructed a data reduction guide for this project, primarily for the use of the student researchers. You may have specialized software such as Maxxim DL which can do reductions for you. Ours instructions are posted here.

Additional information will be added to this site as the project progresses.