Xref: utzoo sci.misc:3966 comp.graphics:9298
Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!umich!yale!cs.utexas.edu!samsung!munnari.oz.au!uniwa!erm!sns
From: sns@erm.oz (Stuart Nixon)
Newsgroups: sci.misc,comp.graphics
Subject: Re: satellite pictures
Summary: Yes, Thermatic images can pick up sub-surface details
Message-ID: <556@erm.oz>
Date: 11 Jan 90 13:05:20 GMT
References: <1523@castle.ed.ac.uk>
Organization: Earth Resource Mapping, Australia
Lines: 23

In article <1523@castle.ed.ac.uk>, nick@lfcs.ed.ac.uk (Nick Rothwell) writes:
> Recently I heard of satellite pictures that revealed buried ruins
> in the Sahara desert. I have a simple question. Is this true ?
> 	Can satellite pictures reveal buried ruins ? Has this
> been done much ?

The short answer is yes.  Many of the commercial satellites (such as Landsat
TM) have a thermal bands, e.g. sensors in the near or far infrared range
(2.2 um to 10um).  If you have an area with a fairly constant surface (such as
desert), then sub-surface variations show up quite clearly.  There has also
been some research in thermal profile mapping, where the rate at which
the surface heats up & cools down is used to guess at what material might
be causing the effect (for example sandstone has a different thermal
profile to granite).

sns


-- 
Stuart Nixon,	sns@erm.oz.au

Earth Resource Mapping, 130 Hay St, Subiaco, Western Australia 6008
Phone: +61 9 388 2900   Fax: +61 9 388 2901   E-mail: sns@erm.oz.au