| Date: | 2010-02-16 12:38:00 | |
| Sender: | Chris Moore, Mt. Stromlo SLR Station <Chris Moore <cmoore@eos-aus.com>> | |
| Subject: | [SLR-Mail] No. 1836: Mt Stromlo Normal Point Data | |
| Author: | Chris Moore, Mt. Stromlo SLR Station | |
| Content: | ******************************************************************************** SLR Electronic Mail 2010-02-16 12:38:00 UTC Message No. 1836 ******************************************************************************** Author: Chris Moore, Mt. Stromlo SLR Station Subject: Mt Stromlo Normal Point Data Dear Colleagues Unfortunately I have to report that mets data in the Mt Stromlo ILRS normal= point files published since 1 October 2008 have been corrupted by a recent= ly identified software bug. This bug was introduced in the new version of t= he post processing software as per SLR Mail 1718. It has now been resolved = with a new version of the software installed on the 8 February 2010. The behaviour of this bug was to incorrectly allocate met data taken early = in a pass to normal points later in a pass, and its effect depended on leng= th of pass, rate of change of mets data and other factors. To assess the po= tential impact of the incorrect mets data, an analysis of all normal point = data produced since Oct 08 was undertaken. The results show that approximat= ely 5% of data from all LEOs and 10-15% of data from Lageos 1 & 2 could lea= d to a range error of 1mm or more. The situation for higher satellites is c= onsiderably worse with 40-50% of data being similarly impacted. On the positive side, data collected with the new software is in a form suc= h that we can relatively easily and quickly reprocess essentially all of th= e affected normal point data and republish the ILRS normal point files cont= aining the correct mets data. Given that the level of impact on normal poin= t data is quite significant, Mt Stromlo has commenced this reprocessing act= ivity and expect to republish most QLNP files for 1 October 2008 - 8 Feb 20= 10 in the near future. A further message will be sent once this activity ha= s been completed. Regretfully yours Chris PS It is somewhat ironic, but we believe that the CRD normal point files pu= blished in this period contain correct data. Dr Christopher Moore Manager, Mt Stromlo SLR Station EOS Systems Pty Ltd 111 Canberra Avenue Griffith ACT 2603 Australia Ph: +61 2 6287 2953 Fax: +61 2 6287 2951 Mobile: 0411 243 227 Email: cmoore@eos-aus.com www.eos-aus.com The information in this email is confidential to the named addressee and su= bject to copyright. No-one else may read, print, store, copy , forward or act in reliance on al= l or any of this email or its attachments. If you are not the intended recipient, any use, reliance upon, disclosure o= r copying of this email is prohibited and unlawful. Electro Optic Systems does not warrant that this email and any attachments = are error or virus free and recommends that all attachments be checked for = computer viruses. From: Chris Moore ******************************************************************************** |