Emulation start date

[victorcionca]

Hello,

When the Observer generates the constellation topology there are two dates used:

• one is the "epoch", used when creating the Satrec object, and it uses start date of 2020-1-1
• the other one is "cur", used when calculating the position of the satellite throughout the emulation; this one is set as 2022-1-1.

What is the reason for using two different start dates? Why not use a single one for both start (epoch = start - since) and cur?
My understanding was that (at least for TLE) the satellite record is only valid for several weeks around the epoch value.

Thanks and regards,
Victor