Prisma Satellites

(Duration of 2 days) LEOP consists of initial acquisition of the COMBINE spacecraft and initial check-out of the power and thermal system as well as some fundamental GNC functions including the momentum management function.

Success criteria for PRISMA LEOP:

Ground has up to date orbit information, preferably from onboard GPS measurements, to predict passages of the spacecraft over Kiruna, and is able to establish two way communication on each pass.
The spacecraft has deployed both its solar array panels and ground has verified this.
The spacecraft has nominal power to all units that are at this stage activated.
Thermally the spacecraft has stable temperatures that are within expected limits.
The spacecraft is stably sun pointing with the –Y axis, and revolving at 1 revolution per hour and has removed the momentum induced by launch vehicle separation.
The spacecraft is in its nominal branch configuration and is able to autonomously stay in that configuration and is not rebooting its core board.
The spacecraft is using its resources within the expected limits.
Read reports here below

Reports:

Commissioning Readiness Review

Two days of the mission has passed and now it is time to decide if we have fullfilled the success criterias of LEOP and are ready to move on to the Commissioning phase.

Yesterday we managed to generate new TLE based on GPS data received from Mango.
Both solar arrays are deployed.
The power checkout is performed and all looks normal.
The thermal checkout is performed and all looks normal.
The tip-off rate was gentle and Mango is now stable, safe sun pointing and revolving one revolution per hour.
All systems and units switched on are on nominal branch and look healthy.
Spacecraft is using its resources as expected.

Enable time synch on Mango was performed during the second pass today at 16:35 UTC so....

We are declared ready for commissioning!

Written by

Anna Carlsson

2010-06-17 / 21:48:08

LEOP Day 2

A new day has started and PRISMA has been out of sight for a few hours. The plans for today is to perform Thermal Checkout of Mango and to verify the Mass Memory of Mango. The first GPS almanac is to be uploaded as a tunable.

During the first pass (15:35 UTC) we were happy to see that everything still looked nominal and PRISMA continue to look healthy. Stig-Ove our contact point at Esrange has generated new TLE for us from the antenna angles generated by Balder (antenna at Esrange) and they work fine.

Written by

Anna Carlsson

2010-06-16 / 21:02:30

Six contacts later

Now during the seventh passage all systems are still showing nominal behavior, no unexpected events so far. Collection of data and commissioning of all subsystems have started. The schedule is proceeding so smooth it is almost a little bit boring, which in fact is a very good thing.

Two separate high precision orbit determinations have been performed successfully, first based on antenna angle measurements and secondly using GPS measurements from Mango. Currently we are tracking eight GPS satellites, which give us a very good position fix.

Written by

Robin Larsson

2010-06-16 / 03:51:08

The first contact with PRISMA

The first contact with PRISMA was expected at 16:15:29. To our great satisfaction our collegues in Kiruna performed an excellent work so the telemtry started to come in

even one minute before the predicted time. We could not have expected a better first pass. The solar arrays were deployed and Mango was safe sun pointing. With a pass duration of around 12 minutes we had plenty of time to upload the planned commands.

PRISMA_Solar Deployd_Skål

Very happy Prisma Operations Team

Written by

Anna Carlsson

2010-06-15 / 19:24:05