Download ERS-2 preliminary (DGM-E04) orbits

Preliminary orbits are available until [an error occurred while processing this directive].
The orbits will be augmented approximately every month on both the NOAA and DEOS ftp sites..

DEOS preliminary ERS-2 orbits are based on the DGM-E04 gravity field model and SLR and OPR1 altimeter crossovers and normal points. Because of the short delay of the availability of OPR1 data these orbits are available a few weeks after the end of each repeat cycle.

The orbits can be downloaded from the DEOS or NOAA ftp servers. The orbits are stored as separate ODR files. Downloading of these files by normal FTP is more practical if you experience bad connections.

Please acknowledge the fact that you have been using the orbits of the Delft Institute for Earth-Oriented Space Research in any publication that is the result of it.
You may cite R. Scharroo and P. N. A. M. Visser, Precise orbit determination and gravity field improvement for the ERS satellites, J. Geophys. Res., 103, C4, 8113-8127, 1998.

What you should do ...

Create a directory on your local system where you want to store the orbit files, e.g.,
```
       mkdir /home/ers2/ODR/dgm-e04.prelim
```
To know which files to download for a particular period, consult the arclist.
Download Method 1:
Use your web browser to download the arclist and individual ODR files:
- First click the or button to select the server closest to you.
  ftp://falcon.grdl.noaa.gov/pub/delft/ODR.ERS-2/dgm-e04.prelim/
  or
  ftp://dutlru2.lr.tudelft.nl/pub/orbits/ODR.ERS-2/dgm-e04.prelim/
- Click with the left mouse botton while holding the shift key down on the ODR files you want to copy into the abovementioned local directory.
- Don't forget to download the arclist file too, and save it in the same directory.
Download Method 2 (preferred):
Use anonymous FTP to download the arclist and individual ODR files:
- Use the ftp command to connect to one of the above addresses (of course the one closest to you).
- Go to the correct directory using ftp's cd command.
- Type bin to switch to binary transfer.
- Download all the ODR files you need into the aforementioned local directory.
- Don't forget to download the arclist file too, and save it in the same directory.
- Tip: Use ftp's prompt to switch of queries about downloading files; finally use e.g. mget arclist ODR.1?? to download the arclist and all ODRs 100-199.
If you have not registered and want to be kept informed of further developments in ERS orbit determination, read the registration info.
Use the orbits at your own leasure, in connection with the orbit interpolation software.

This page was created by Remko Scharroo, remko.scharroo@noaa.gov
It is currently maintained by Eelco Doornbos, e.n.doornbos@tudelft.nl