Hello All,

    I received the following message through our local GIS user list and
thought that some of you may be interested.  Linda Zellmer
 Linda Zellmer <[log in to unmask]>

------------------------------------------
From: Sokhan Hing [ mailto:[log in to unmask] <mailto:[log in to unmask]> ]
Sent: Tuesday, May 22, 2001 6:22 AM
Subject: LANDSAT 5


Recent decisions by the US Geological Survey have placed the current
configuration of Landsat satellites in jeopardy.  The Department of the
Interior, through the USGS, has quietly announced that it intends to
decommission (i.e. terminate) the Landsat 5 satellite (see

<http://www.usgs.gov/public/press/public_affairs/press_releases/pr1455m.html
>
http://www.usgs.gov/public/press/public_affairs/press_releases/pr1455m.html)

.

In order to allow further time for both public and private organizations to
express concerns and possibly justify the need for continuation of the
Landsat 5 satellite, an immediate delay in the termination of this satellite

would be necessary.

Many (perhaps most) users of Landsat 5 may still be unaware of its imminent
termination, which according to the latest information will likely be early
June.  Space News has also recently posted an article on the subject (see
http://www.space.com/spacenews/remotesensing/landsats_decommissioned_010516
<http://www.space.com/spacenews/remotesensing/landsats_decommissioned_010516
> .
html).

Landsat 5's extraordinary long life of nearly 17 years has allowed a
continuing program of earth observation, from its launch through the period
of the loss of Landsat 6 to the successful launch of Landsat 7 in 1999.
Landsat 5 imaging appears to be at very near the level of Landsat 7.  The
cost of maintaining the continued full operation of Landsat 5 is between two

and three million dollars per year (estimated to be less than 1% of the cost

of a new satellite). The cost of at least maintaining its capability as an
on-orbit backup would likely be even less.

One recognized advantage of having two operational (US) Landsat satellites
is to allow timely tracking of land surface change, particularly vegetation
change world wide, whereas a one-satellite configuration is less reliable
because of cloud cover. Clearly there are many other advantages of
maintaining both Landsat 5 and 7 in complementary orbits, if not reserving
Landsat 5 on-orbit as a spare.

If the maintenance of Landsat 5 capability is important to your operations,
or may be important to future data applications, you are encouraged to voice

your concerns on this issue to the USGS contact, Ray Byrnes, at
mailto:[log in to unmask] <mailto:[log in to unmask]> .