MISSION PLAN - PDS Small Bodies Node

All 34-m HEF
except selective
70-m from
L+1789 to +1804d
L+1733 to +1741d: 2*4 h/w
L+1741 to +1747d: 2*8 h/w
L+1747 to +1784d: 4 h/d
L+1784 to +1789d: 8 h/d
L+1789 to +1794d: 24 h/d
L+1796 to +1799d: 24 h/d
L+1799 to +1801d: 4 h/d
L+1801 to +1804d: 24 h/d
L+1804 to +1835d: 4 h/d
L+1835 to +1841d: 2*4 h/w
1. DSN Coverage should alternate between Northern Hemisphere and Southern Hemisphere DSN sites.
2. A*B = A number of tracks at B frequency
Table 6.3-2 OPNAV Plan
Time
Frequency
no. of
images
bits /
pixel
no. of
filters
E -90 to -7 d 2 /wk 1 16 1
(nav)
E -7 to -2 d 1 per day same as above
E -47 to -26 h 1 per hour same as above
E -17 to -12h 1 per hour same as above
Comments
small yaw turn, mirror, pattern match
and window.
During the Post Encounter subphase, the primary objective is to transmit all of the data
stored during the comet encounter. The spacecraft attitude for the first 19 days after
encounter is planned to track the Earth with the HGA boresight to reduce spacecraft
slewing. It is highly desirable to return this data as quickly as possible to prevent
irretrievable loss in the event of a reboot of the spacecraft main computer. In addition,
transmission of the data a total of three times is also desired to prevent loss of data due to
communications problems. Approximately 55 hours are estimated to be required using
HGA and 70-m capability (4000 bps) to return the stored data. With the HGA and 34-m
capability (1000 bps), 220 hours are required to return the same data set. Tracking with
70-m stations is requested to support three 55 hour periods with 1 day between each
period to allow for spacecraft health and safety verification.
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