Tammy Jones (Phone: 301/286-5566) Tammy.L.Jones.1@ gsfc.nasa.gov

March 17, 1997

HUBBLE SPACE TELESCOPE STATUS REPORT

The activities and testing being carried out as part of the Hubble Space Telescope's (HST's) Servicing Mission Orbital Verification continue to go well and on schedule. The telescope and all newly-installed components are operational and returning data which are being examined and analyzed in a timely manner by the science instrument teams, the HST project, and the Space Telescope Science Institute.

The Near-Infrared Camera and Multi-Object Spectrometer (NICMOS), one of the new science instruments, had a busy week as detailed "focus sweeps" were executed for all three cameras. The purpose of the focus sweep is to observe external stellar targets at a variety of focus positions (both in- and out-of-focus), and thereby determine the best focus setting in each camera (This is similar to the back-and-forth rotation of the focusing ring that is adjusted before taking a photograph with a single-lens-reflex camera.). Knowledge of these settings will be important for NICMOS's formal science program, which will begin in several months.

HST's other new science instrument, the Space Telescope Imaging Spectrograph (STIS), continued to perform extremely well in a variety of tests. The spectrum of a standard star taken using the charge coupled device (CCD) detector showed, as expected, that it was highly responsive to light. Measurement of the widths of "emission lines" produced by the instrument's internal calibration lamps show that STIS has superb spectral resolution across the field of view of the CCD. Optical alignment data show that STIS is very close to its final alignment.

HST received a refurbished Fine Guidance Sensor (FGS) during the servicing mission. The refurbished FGS has returned excellent data of its so-called "S-curves," which are critical to precise guiding of the telescope. There are three FGSs on HST, two of them original and onboard since the 1990 launch; the refurbished FGS looks to be the superior one of the three. Further characterization of the performance of the refurbished FGS is planned in the weeks ahead.

The Wide-Field and Planetary Camera-2 (WFPC-2), installed on HST in 1993, has resumed its formal science operations. Approximately 315 images were taken for 25 science programs. This instrument continues to perform exceptionally well. All other hardware components on HST, including the new Solid State Recorder (SSR), are working and performing nominally. The latest WFPC-2 image, planetary nebula (NGC 2346), is available at the following site: http://www.stsci.edu/pubinfo/pr/97/07.html

The first HST status report noted both new science instrument's susceptibility to particle radiation in the South Atlantic Anomaly. NASA is continuing to work on software and operational changes. Both instruments are expected to carry out their full science programs.