为Landsat5 默哀用过TM图像的同学大有人在吧

xenokook · 发表于 2011-11-21 09:32

Landsat 5 Mission in Jeopardy
Released: 11/18/2011 9:32:01 AM

Contact Information:
U.S. Department of the Interior, U.S. Geological Survey
Office of Communications and Publishing
12201 Sunrise Valley Dr, MS 119
Reston, VA 20192

Jon Campbell

Phone: 571-230-6831

The U.S. Geological Survey (USGS) has stopped acquiring images from the 27-year-old Landsat 5 Earth observation satellite due to a rapidly degrading electronic component.
Landsat 5 was launched in 1984 and designed to last 3 years. The USGS assumed operation of Landsat 5 in 2001 and managed to bring the aging satellite back from the brink of total failure on several occasions following the malfunction of key subsystems. There is now an increasing likelihood that the Landsat 5 mission is nearing its end.
“This anticipated decline of Landsat 5 provides confirmation of the importance of the timely launch of the next Landsat mission and the need for an operational and reliable National Land Imaging System,” stated Anne Castle, Assistant Secretary for Water and Science at the U.S. Department of the Interior. “The USGS is committed to maintaining the unique long term imaging database that the Landsat program provides.”
For several months, the Landsat flight operations team has been closely tracking the fluctuating performance of an amplifier essential for transmitting land-surface images from the Landsat 5 satellite to ground receiving stations in the U.S. and around the world.  Over the past 10 days, problems with the amplifier have led to drastically reduced image download capabilities, a sign of impending failure.
Numerous engineering and technical adjustments have been made to Landsat 5 in the past several days to sustain at least a limited imaging capability, but performance has continued to decline.  Instead of continuing to operate until the amplifier fails completely, which could bring the mission to an end, USGS engineers have suspended imaging activities for an initial period of 90 days in order to explore every possible option for restoring satellite-to-ground image transmissions.
The USGS-operated Landsat 7 remains in orbit collecting global imagery. Since its launch in 1999 with a 5-year design life, Landsat 7 has experienced an instrument anomaly which reduces the amount of data collected per image.  Landsat 8, currently called the Landsat Data Continuity Mission, is now scheduled to be launched in January 2013.

转自http://landsat.usgs.gov/

zhongbuzhong · 发表于 2011-11-21 11:03

抢个沙发，虽然看不懂。

xenokook · 发表于 2011-11-21 13:15

我比较懒直接粘贴了大概讲的是
Landsat5 卫星也就是我们常用的TM影像的传感器，是Landsat系列卫星中服役时间最长获取资料最多也是最成功的卫星。最近出现了严重的问题，虽然经过工程师的维护，但还是不得不宣布暂时停止获取影像。而按照这种趋势发展很可能永远会停止工作。
TM的影像整整影响了一个时代，现在几乎所有讲遥感或者图像处理的书籍都会提到这种影像。最宝贵他的长时间序列的影像很多都是那个时代的唯一。