Record Search Query: [Source_Name: Short_Name='GRACE']
The Earth and Moon Viewer
Entry ID: EARTHVIEW
Abstract: The Earth and Moon Viewer allows users to view a map of the Earth showing the
day and night regions at this moment, or view the Earth from the Sun, the Moon,
the night side of the Earth, above any location on the planet specified by
latitude, longitude and altitude, from a satellite in Earth orbit, or above
various cities around the globe.
Images can be generated based on a full-color image of ... the Earth by day and
night, a topographical map of the Earth, up-to-date weather satellite imagery,
or a composite image of cloud cover superimposed on a map of the Earth, a
color composite which shows clouds, land and sea temperatures, and ice, or the
global distribution of water vapor. Expert mode allows you additional control
over the generation of the image. Users can compose a custom request with
frequently-used parameters and save it as a hotlist or bookmark item in your
Users can also view the moon from the Earth, Sun, night side, above named
formations on the lunar surface. or as a map showing day and night. You can
also make expert and custom images of the Moon.
[Summary provided by John Walker.]
ISO Topic Category
Access Constraints To use the Earth and Moon Viewer, you need a graphical Web browser with forms
support and the ability to display GIF and JPEG images. In order to pan around
the map or globe by clicking within the image, your browser must support
Client-Side Image Maps--if you don't know what this means, don't worry: if your
browser doesn't support the feature, you'll see a page which explains how to
Use Constraints The Earth Viewer was first implemented by John Walker in December 1994. Most of
the software that generates the various views of the Earth was adapted from
Home Planet for Windows. See the details for additional implementation
information. The satellite tracking code is based upon the N3EMO Orbit
N3EMO Orbit Simulator routines v3.7
... Copyright 1986,1987,1988,1989,1990 Robert W. Berger N3EMO
May be freely distributed, provided this notice remains intact.
The GIF output file generation is based upon the ppmtogif module of Jef
Poskanzer's pbmplus toolkit, of which many other components were used in
creating the images you see here. The Netpbm toolkit is a much-extended version
of pbmplus; Earth and Moon Viewer was developed using only pbmplus components.
ppmtogif.c - read a portable pixmap and produce a GIF file
Based on GIFENCOD by David Rowley [firstname.lastname@example.org].
Lempel-Ziv compression based on "compress".
Modified by Marcel Wijkstra [email@example.com]
Copyright 1989 by Jef Poskanzer.
Permission to use, copy, modify, and distribute this software and its
documentation for any purpose and without fee is hereby granted, provided that
the above copyright notice appear in all copies and that both that copyright
notice and this permission notice appear in supporting documentation. This
software is provided "as is" without express or implied warranty.
The Graphics Interchange Formal is the Copyright property of CompuServe
Incorporated. GIF(sm) is a Service Mark property of CompuServe Incorporated.
Meeus, Jean. Astronomical Algorithms . Richmond: Willmann-Bell, 1998. ISBN
Creation and Review Dates