Where is LADEE Now, and where is it going?
After the successful launch of LADEE last Friday:
you may be wondering where the LADEE spacecraft is now, and what are the next steps on the trajectory. So here we are, LADEE on Sept 11, 9 AM PDT:
LADEE on Sept 11, 2013
Note the upcoming phasing loops (dotted) and the Moon to the upper right. Of course this is a 3-D picture, and you can get a better feel for where the Moon is now here:
LADEE on Sept. 11, 2013 with Moon (side view)
We (LADEE Flight dynamics) often like to look at the lunar trajectories in an Earth-Moon rotating frame. The Earth is at the middle, the Moon at the top:
LADEE on Sept. 11 (Earth-Moon Rotating Coordinate frame)
On Sep. 13, 2013, LADEE will reach first perigee:
LADEE at first perigee
The first orbit-raising maneuver (after the test maneuver on Sep. 11) will occur here. This maneuver is called Perigee Maneuver 1 (PM1) and will raise LADEE’s orbit and change the orbit period from 6.44 days to 7.6 days. This brings us to perigee 2 on Sep. 21, 2013:
Perigee 2
From here we perform PM2, and raise the orbit period to 10 days. We get back to perigee 3 on Oct. 1, 2013:
Perigee 3
We have no nominal burn at Perigee 3 (although we may perform a trajectory correction maneuver there, and one more 36 hrs later for our final precise targeting to our Lunar arrival conditions).
Finally, we take a 5-day transfer to the Moon, where we arrive on Oct. 6, 2013 for our first Lunar Orbit Insertion burn (LOI-1). We use 3 maneuvers for Lunar capture, which we will describe in another post.
Lunar Approach
Here’s a few more pictures of the complete LADEE trajectory:
Complete LADEE Trajectory, Earth Centered Inertial coordinate frame.
Complete Lunar Transfer trajectory, Earth-Moon Rotating Coordinate Frame
