The joint U.S. and German Stratospheric Observatory for Infrared Astronomy (SOFIA), a program to develop and
operate a 2.5-meter infrared airborne telescope in a Boeing 747SP, has obtained first science with the FORCAST camera
in the 5 to 40 micron spectral region and the GREAT heterodyne spectrometer in the 130 to 240 micron spectral region.
We briefly review the characteristics and status of the observatory. Spectacular science results on regions of star
formation will be discussed. The FORCAST images show several discoveries and the potential for determining how
massive stars form in our Galaxy. The GREAT heterodyne spectrometer has made mapping observations of the [C II]
line at 158 microns, high J CO lines, and other molecular lines including SH. The HIPO high speed photometer and the
high speed camera FDC were used to observe the 2011 June 23 UT stellar occultation by Pluto.
A key to the success of the Spitzer Space Telescope (formerly SIRTF) Mission was a unique management structure that
promoted open communication and collaboration among scientific, engineering, and contractor personnel at all levels of
the project. This helped us to recruit and maintain the very best people to work on Spitzer. We describe the management
concept that led to the success of the mission. Specific examples of how the project benefited from the communication
and reporting structure, and lessons learned about technology are described.
The joint U.S. and German SOFIA project to develop and operate a 2.5-meter infrared airborne telescope in a Boeing
747-SP is in its final stages of development. Flying in the stratosphere, SOFIA allows observations throughout the
infrared and submillimeter region, with an average transmission of greater than 80%. SOFIA's first generation
instrument complement includes high-speed photometers, broadband imagers, moderate resolution spectrographs
capable of resolving broad features due to dust and large molecules, and high resolution spectrometers suitable for
kinematic studies of molecular and atomic gas lines at km/s resolution. These instruments will enable SOFIA to make
unique contributions to a broad array of science topics. First science flights will begin in 2010, and the observatory is
expected to operate for more than 20 years. The sensitivity, characteristics, science instrument complement, future
instrument opportunities and examples of first light science will be discussed.
The joint U.S. and German Stratospheric Observatory for Infrared Astronomy (SOFIA) Project will operate a 2.5-meter
infrared airborne telescope in a Boeing 747SP. Flying in the stratosphere at altitudes as high as 45,000 feet, SOFIA
enables observations in the infrared and submillimeter region with an average transmission of 80%. SOFIA has a wide
instrument complement including broadband imaging cameras, moderate resolution spectrographs capable of resolving
broad features due to dust and large molecules, and high resolution spectrometers suitable for kinematic studies of
molecular and atomic gas lines at km/s resolution. The first generation and future instruments will enable SOFIA to
make unique contributions to a broad array of science topics. SOFIA began its post-modification test flight series on
April 26, 2007 in Waco, Texas and will conclude in winter of
2008-09. SOFIA will be staged out of Dryden's aircraft
operations facility at Palmdale, Site 9, CA for science operations. The SOFIA Science Center will be at NASA Ames
Research Center, Moffet Field, CA. First science flights will begin in 2009, the next instrument call and first General
Observer science call will be in 2010, and a full operations schedule of ~120 flights per year will be reached by 2014.
The observatory is expected to operate for more than 20 years. The sensitivity, characteristics, science instrument
complement, future instrument opportunities, and examples of first light and early mission science are discussed.
Launched from Kennedy Spaceflight Center in the early morning of August 25, 2003, NASA's Spitzer Space Telescope (formerly Space Infrared (IR) Telescope Facility, SIRTF) is the fourth and final facility in the Great Observatories Program. It joins Hubble Space Telescope (HST, 1990), the Compton Gamma-Ray Observatory (CGRO, 1991-2000), and the Chandra X-Ray Observatory (CXO, 1999). Spitzer has a sensitivity that is two to three orders of magnitude higher than that of previous ground-based and space-based infrared observatories. It is revolutionizing our understanding of the creation of the universe, the formation and evolution of galaxies, the genesis of stars and planets, and the chemical evolution of the universe. A brief overview of infrared (IR) astronomy and of Spitzer's role in the science of IR is given. The history, construction, launch, and in-orbit checkout of the observatory is reviewed. Science highlights from the first two and a half years of observations are presented. Further information about the Spitzer can be found on the WEB at http://spitzer.caltech.edu/.
We describe the process by which the NASA Spitzer Space Telescope (SST) Cryogenic Telescope Assembly (CTA) was brought into focus after arrival of the spacecraft in orbit. The ground rules of the mission did not allow us to make a conventional focus sweep. A strategy was developed to determine the focus position through a program of passive imaging during the observatory cool-down time period. A number of analytical diagnostic tools were developed to facilitate evaluation of the state of the CTA focus. Initially, these tools were used to establish the in-orbit focus position. These tools were then used to evaluate the effects of an initial small exploratory move that verified the health and calibration of the secondary mirror focus mechanism. A second large move of the secondary mirror was then commanded to bring the telescope into focus. We present images that show the CTA Point Spread Function (PSF) at different channel wavelengths and demonstrate that the telescope achieved diffraction limited performance at a wavelength of 5.5 μm, somewhat better than the level-one requirement.
The NASA Space Infrared Telescope Facility (SIRTF) contains an 85 cm cryogenically cooled beryllium Ritchey-Chretien telescope. This Cryogenic Telescope Assembly (CTA) will operate at about 5 K. Once in orbit, the telescope may be focused by moving the secondary mirror using a cryogenic focus mechanism to vary the separation between the primary and secondary mirrors. The risk of failure of the motor is unknown but is believed to be non-negligible. It is therefore desirable to evaluate and achieve best focus with a minimum number of motor activations. The SIRTF Project has charged an Integrated Products Team (IPT) with conducting this activity. We describe a strategy to determine the initial mirror spacing by quantitatively evaluating the shapes of the images formed by the telescope using the Infrared Array Camera (IRAC) and other science instruments (SI's). We show that this information can be used to predict the direction and magnitude of the secondary mirror move that will result in the telescope best focus. The tools used to evaluate focus position and ptical quality of the in orbit CTA have been qualified during the ground-based BRUTUS test are here described. Future activities of the IPT to meet IOC objectives are summarized.