These are the "Living Earth" images.
See here for an example;
http://www.fourmilab.to/cgi-bin/uncgi/Earth/action?opt=-p
(this interface is optimised for providing a rounded globe appearance)
and try here for customised results;
http://www.fourmilab.to/earthview/custom.html
For some reason it appears to be very difficult to receive "flat earth"
images suitable for wallpaper from the site, as it seems to be designed to
primarily display in a rounded globe format.
For a 1024 x 1024 version equivalent to the image on the website link, try
the following;
http://www.fourmilab.to/cgi-bin/unc...date=1&utc=2006-03-30+18:25:43&jd=learth.evif
Here's one of the South Pacific including Australia, New Zealand and PNG;
http://www.fourmilab.to/cgi-bin/unc...&date=1&utc=2006-05-10+5:25:43&jd=learth.evif
Should you wish to "tinker" with the url I provided, you can get suitable
images according to your own requirements.
All requests will start with the following baseline url;
http://www.fourmilab.to/cgi-bin/uncgi/Earth?
followed by the size of the image;
imgsize=1024 (in this case 1024 pixels, could be 800, 640 etc 1024
maximum)
followed by;
&opt=-z (haven't tinkered with this, so as is will be fine)
then latitude;
&lat=44&ns=North (44 degrees North in this instance, can be North or
South)
then longtitude;
&lon=4&ew=West (4 degrees West, can be East or West)
then altitude;
&alt=60 (as in kilometres above - 60 in this case)
image placeholder;
&img=
then the date and time you wish to apply to the image;
&date=1&utc=2006-03-30+18%3A25%3A43 (equivalent to 30 March 2006: 18:25:43
in form YEAR-MN-DY+HH%3AMM%3ASS - the %3A between the HH MM SS needs to be
retained in the url and not confused with being part of the time string)
and finally the base image source;
&jd=learth.evif (as in the Living Earth series)