Chapter
8    




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Windows of Opportunity: Photo Survey of the
Mir Earth Observation Windows



Premkumar B. Saganti

Image Science and Analysis Group
Lockheed Martin Space Operations Company
Houston, Texas USA

Kamlesh P. Lulla

Office of Earth Sciences
NASA Johnson Space Center
Houston, Texas USA

Abstract

Understanding the impact of the harsh space environment on windows used for Earth observations from Mir is important for planning scientific observations through windows on the International Space Station. Shuttle-Mir Missions provided unique opportunities to document the current condition of the optical windows of Mir that have been exposed to the space environment for over a decade. We present results of the photo survey of windows in Mir's Base Block, Kvant-2 and Priroda modules. These windows were used for most of the Earth observation activities by the astronauts and cosmonauts during Shuttle-Mir missions. The survey reveals some probable micrometeoroid and orbital debris (MMOD) impacts, translucency of window surfaces, bright spots that could have been the contamination deposits on the external panes, and other unique patterns on the window surfaces. It is conceivable that these impacts affect the quality the Earth observation imagery obtained through these windows. Qualitative descriptions of selected window panes are provided with photo illustrations and image enhancements.

Citation for the published article

Saganti, P. B., and K. P. Lulla, 2000. Windows of opportunity: Photo survey of the Mir Earth observations windows, in Dynamic Earth Environments: Remote Sensing Observations from Shuttle-Mir Missions (K. P. Lulla and L. V. Dessinov, eds.), John Wiley & Sons, New York, pp. 121-129, 266, 280.



Links to Color Images

Figure 8.1 The Mir complex as seen from the Space Shuttle (70-mm film, NASA photograph STS091-727-55, June 1998).
Figure 8.2 Diagram of the Mir configuration, highlighting in color indicates modules containing windows in the survey: Base Block, Kvant-2, and Priroda.
Figure 8.3 Overview image of Base Block window 6 shows a probable MMOD strike towards the left lower corner and a cluster of bright dots at the center of the window (35-mm film, NASA photograph NASA6-331-6).
Figure 8.4 Four-month comparison of Base Block window 6. Arrows indicate features common to both images. Lower arrow marks a new set of bright spots, probably due to external contamination deposits (video, NASA6 ID 461707, NASA7 ID 461952).
Figure 8.5 Images of Base Block window 2 show temporal changes between the left image (NASA-2, September 1996) and the right image (NASA-7, April 1998). On the right, the window shows a scratch/scuff mark towards the left of the image. The object on the left edge of each window image is the tip of a solar array panel (video, NASA2 ID 611787, NASA7 ID 461952).
Figure 8.6 An overview image shows a scratch/scuff mark on Base Block window 1 (video, NASA7 ID 461952).
Figure 8.7 The prominent translucent appearance of the outer periphery of Kvant-2 window V covers nearly 60 % of the window area, as observed during NASA 5 (35-mm film, NASA photograph NASA5-308-14).
Figure 8.8 The haze/translucent area shown in video images of Kvant-2 window V decreased from 60% to 40% of the window surface area between July 1997 (left, video, NASA5 ID 461810) and February 1998 (right, video, NASA7 ID 461952).
Figure 8.9 This overview image of Priroda window 1 in April 1998, shows a dark pattern in the center of the window and concentric rings of haze contributing to a translucent appearance away from the window center (video, NASA7 ID 461952).
Figure 8.10 Temporal changes in Priroda window 1 occurred during NASA 7 and are illustrated in these video images (left, February 1998; right, April 1998; video, NASA7 ID 461952). Arrows point to new set of bright spots interpreted to be external contamination deposits.