“A fully rotating mechanical digital camera is placed in the gallery space. Its rotating position is also activated by the angular movements of the telescope. The 2^nd projection on the opposite wall features what the camera sees. Spectators are invited to position themselves in front of the camera thereby metaphorically integrating themselves into the visual field of the telescope. All the visualizations are based on real data received from the NASA Spitzer Space Center. ”

cam_rotating-1

“Hidden in visible light

-Here the light we see is also generated by stars, but now it better traces the smaller, cooler ones. Notice how the the lanes of dust have become partially transparent, allowing us to see things that are hidden in visible light. Our view of the central bulge of stars in our own Milky Way galaxy is particularly striking since it is almost completely obscured at shorter wavelengths! The bottom images show these regions in the far-infrared (infrared wavelengths farther from visible light). At these wavelengths, stars hardly emit any light at all. Instead almost everything we see is generated by the dust clouds themselves. The dust, which is colder than the coldest arctic night on earth, is still warm enough to emit the thermal infrared radiation seen here.”

“Redshifted and the young Universe

Astronomers have discovered that all distant galaxies are moving away from us and that the farther away they are, the faster they are moving. This recession of galaxies away from us has an interesting effect on the light emitted from these galaxies. When an object is moving away from us, the light that it emits is “redshifted”. This means that the wavelengths get longer and thereby shifted towards the red part of the spectrum. This effect, called the Doppler effect, is similar to what happens to sound waves emitted from a moving object. For example, if you are standing next to a railroad track and a train passes you while blowing its horn, you will hear the sound change from a higher to a lower frequency as the train passes you by. As a result of this Doppler effect, at large redshifts, all of the ultraviolet and much of the visible light from distant sources is shifted into the infrared part of the spectrum by the time it reaches our telescopes. This means that the only way to study this light is in the infrared.”

What Spitzer found?
http://www.spitzer.caltech.edu/Media/happenings/20050825/

Podcasts
http://www.spitzer.caltech.edu/features/podcasts/index.shtml

Applications to Art and Art History

http://coolcosmos.ipac.caltech.edu/cosmic_classroom/light_lessons/
our_world_different_light/historical.html

“Invisible text on the Dead Sea Scroll (left or top) and preservation efforts on the original Star Spangled Banner. Infrared imaging has been used to gather new information about historical objects and to help in their preservation and restoration. In 1993, a JPL researcher used infrared photography to reveal previously invisible details on fragments of the Dead Sea Scrolls.

Infrared imaging is routinely used in art conservation activities, and in the authentication and dating of artwork. Infrared technology is used to reveal underpaintings (images painted under paintings) by famous artists of the past, as well as to detect the faded pigments in ancient rock paintings”

http://coolcosmos.ipac.caltech.edu/cosmic_classroom/light_lessons
/our_world_different_light/historical.html

InfraRed

“Which is (electromagnetic radiation) between wavelengths of about 1 and 300 microns (a micron is one millionth of a meter). The human eye detects only 1% of light at 0.69 microns, and 0.01% at 0.75 microns, and so effectively cannot see wavelengths longer than about 0.75 microns unless the light source is extremely bright.”

“Increasing the number of cataloged astronomical sources by about 70%.

The first of these satellites - IRAS (Infrared Astronomical Satellite)
detected about 350,000 infrared sources, increasing the number of cataloged astronomical sources by about 70%.”

Instruments:

* Infraed Array Camera (IRAC)
* InfraRed Spectrograph
* Multiband Imaging Photometer

http://ssc.spitzer.caltech.edu/obs/
http://ssc.spitzer.caltech.edu/documents/exoplanetmemo.txt

“Weather, and other investigations requiring high precision relative photometry (HPRP) with IRAC is different than most IRAC observations described in Spitzer Observing Manual. For the HPRP observations, it is important to maximize source signal-to-noise while minimizing systematic effects; therefore, observers should integrate with the longest possible frametime that does not saturate (stellar photometry mode is very useful in these cases) and collect data in staring mode (no dithers) with as many repeats as needed to cover the desired duration (e.g. transit, rotation period). For bright sources (2-3 times the published saturation limits) which may saturate in even the shortest provided integration time, the observations can still be done, but the source will need to be centered at the corner of a pixel to spread the flux and place the center pixels below saturation. To place a source at the corner of a pixel use a fixed cluster target with array offsets of 0.6 arcseconds in each direction and select the “observe offsets only” option.”

About the Orbit (foto every 5 minutes)
http://www.spitzer.caltech.edu/about/soap-capture.jpg

“Earth-trailing solar orbit. This unique orbit places Spitzer far enough away from the Earth to allow the telescope to cool rapidy without having to carry large amounts of cryogen (coolant). This innovative approach has significantly reduced the cost of the mission.”

Orientation and position

http://www.spitzer.caltech.edu/about/now.shtml

“Spitzer is currently scheduled to be taking science observations.

The image on the right is a screen capture from a computer that continuously predicts Spitzer’s current position in the solar system. You can click on the image to view it at high resolution (1024×676). The panel in the upper left shows Spitzer’s current orientation as seen from Earth, and the right shows where Spitzer is relative to the Earth. The picture is scheduled to update every 5 minutes.”

Current Observation Details

Target Name:
bootes49_3

RA:
4:28: 0.00

Declination:
33:50: 0.00

Program Name:
SDWFS 4

Principal Investigator:
Stern

AOT:
iracmap

Start Time:
2008-03-07 06:43:41

Duration of Observation:
181.63 minutes

How To Read This Chart

“Target Name: This is the name of the object being observed by Spitzer. The name appears as it was input by the observer, and will usually appear as a unique, universally accepted catalog designation rather than a “name” in the traditional sense of the word.

RA & Declination: These are the coordinates in the sky where the object is located. They work much like longitude and latitude on Earth. RA is the object’s position along the equator, and Declination is its position north or south (positive numbers are the northern sky, and negative numbers are the southern sky).

Program Name: When astronomers are granted observing time on Spitzer, their planned observations are defined under a unique program name. Each program has specific goals and objectives, such as the various Legacy Science programs, whose objective is to create a substantial and coherent database of archived observations that can be used by subsequent Spitzer researchers.

Principal Investigator: This is the name of the scientist who leads the team of people who are making the observation on Spitzer.

AOT: This is the specific observing mode that Spitzer is using for its observation. Spitzer has three different instruments (IRAC - The Infrared Array Camera, IRS - The Infrared Spectrograph, and MIPS - The Multiband Imaging Photometer for Spitzer), all of which can be used in several different ways.

Start Time: The time that the observation began. The times are given in UTC (also known as Greenwich Mean Time), which is 8 hours ahead of Pacific Standard Time (7 hours ahead of Pacific Daylight Time).

Duration of Observation: Different observations require different amounts of time to gather all the data. Some observations can be quite quick, and some can take hours.”

The files and formats

“A Spitzer Space Telescope observer interfaces with the Observatory and the instruments by means of Astronomical Observation Templates (AOTs). An AOT, one for each of the eight Spitzer observing modes, permits the user to unambiguously define the parameters of their observing program. The AOT is a central design concept to Spitzer Science Operations. An observation that has been fully defined by supplying parameter values for an AOT is known as an “Astronomical Observation Request” (AOR). Observers use Spot to enter the target information and the observation details into the AOT to create AORs, and ultimately to submit their proposal along with their AORs.”

“An AOR can be thought of as a list of parameters that (when properly interpreted) describe completely an observation. The completed AORs are deposited into the Spitzer databases. Specially designed software expands each AOR into activities and an uplink sequence for transmission to the spacecraft. It is important to realize that the process of creating commands to carry out an observation based on the AOR parameters is done by software, not by support astronomers at the SSC.”

“AORs (and related engineering requests) are the basic building blocks for Observatory scheduling. AORs also define unit data sets for pipeline data processing and science archiving.”