Subject: Re: Mars Science Lab (MSL) Entry/Descent/Landing (EDL)
From: Daniel Adamo <[email-masked]>
Date: Tue, 24 Jul 2012 14:41:27 -0700

ATIG Members-

With help from one among our ranks, I've traced the 3-min skew to an error
on my part in converting events from solar system barycentric time to UTC.
As penance, I shall attend this Friday's Trajectory Think Tank discourse on
time measurement by JSC-DM/Brian Kubena.  This error has been corrected in
the attached "r1" revision to my 22 July upload, which is hereby completely
superseded.  Happy landings!

-Dan

From: Daniel Adamo <[email-masked]>
Date: Sun, 22 Jul 2012 08:27:32 -0500
Conversation: Mars Science Lab (MSL) Entry/Descent/Landing (EDL)
Subject: Mars Science Lab (MSL) Entry/Descent/Landing (EDL)

ATIG Members-

You'll find attached my analysis of what I believe to be the latest and most
authoritative MSL EDL data available to the public at this time.  Those of
us who attended JSC-DM/Gavin Mendeck's excellent presentation on this topic
at June 29's Trajectory Think Tank will note EI (and presumably other
events) in the attachment is about 3 min later than in Gavin's Chart #10.
I'm suspicious this time skew is by design and is an attempt to delay MSL
landing in order to obtain better EDL real time data relay coverage.   The
relay function is provided through Mars Odyssey, which recently suffered a
reaction wheel failure and may otherwise be unable to establish contact with
MSL until after landing.

I've been unable to verify the 3-min skew is real beyond a well written 16
July report on the relay difficulty by Jonathan Amos at
http://www.bbc.co.uk/news/science-environment-18861463.  Reports at
http://mars.jpl.nasa.gov/msl/news/whatsnew/ are terse and do not confirm or
refute the skew's existence.  If anyone's in a position to provide better
EDL planning data to me, I'm willing to revise the attached PDF accordingly
and distribute to ATIG.

-Dan