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Earth’s closest neighbor is holding a secret. In 1999, hints of that secret were revealed in the form of concentrated hydrogen signatures detected in permanently shadowed craters at the lunar poles by NASA’s Lunar Prospector. These readings may be an indication of lunar water and could have far-reaching implications as humans expand exploration past low-Earth orbit. The Lunar CRater Observing and Sensing Satellite (LCROSS) mission is seeking a definitive answer.
 
Earth’s closest neighbor is holding a secret. In 1999, hints of that secret were revealed in the form of concentrated hydrogen signatures detected in permanently shadowed craters at the lunar poles by NASA’s Lunar Prospector. These readings may be an indication of lunar water and could have far-reaching implications as humans expand exploration past low-Earth orbit. The Lunar CRater Observing and Sensing Satellite (LCROSS) mission is seeking a definitive answer.
  
=== Required add-ons ===
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=== required add-ons ===
* [http://users.kymp.net/p501474a/Orbiter/Orbiter.html IMFD 4.2.2]
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* [http://koti.mbnet.fi/jarmonik/Orbiter.html IMFD 5.1m]
* [http://orbithangar.com/showAddon.php?id=f12093c1-4d5e-4a57-b2e2-427a205f82ee Multistage2015 for Orbiter 2010] (install the add-on and copy "Multistage2015.dll" under the "Modules" folder to "Multistage2.dll")
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* [http://users.swing.be/vinka/ Multistage2(full package)]
  
=== Optional add-ons ===
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=== optional add-ons ===
  
 
* [http://orbithangar.com/searchid.php?ID=3165 Attitude MFD]  
 
* [http://orbithangar.com/searchid.php?ID=3165 Attitude MFD]  
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'''NOTE:''' LC-41 is automatically deleted when focus vessel is above 100km alt.
 
'''NOTE:''' LC-41 is automatically deleted when focus vessel is above 100km alt.
  
== Add-on Notes and Quick Info ==
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== Procedures ==
'''NOTES'''
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Accuracy of burns in this mission is '''CRITICAL'''.
 +
During this mission, especially after the TLI burn, we will be using the tools TransX or IMFD to get the '''DIRECTION''' of our burns, and using IMFD map to monitor in real time the '''MAGNITUDE''' of the DeltaV we are imparting. For this mission, usually the AUTOBURN button is '''NOT''' your friend.
  
''Moon Orientation''<br>
 
 
The precession of the Moon's axis is not modelled in Orbiter. To ensure accuracy of the Moon's orientation at the time of the mission, the LRO add-on uses a custom sol.cfg and moon.cfg located in the Config/LRO/ directory. To use them, the "Environment" entry in the scenario file must point to the LRO/sol.cfg.
 
The precession of the Moon's axis is not modelled in Orbiter. To ensure accuracy of the Moon's orientation at the time of the mission, the LRO add-on uses a custom sol.cfg and moon.cfg located in the Config/LRO/ directory. To use them, the "Environment" entry in the scenario file must point to the LRO/sol.cfg.
 
e.g.
 
e.g.
 
  BEGIN_ENVIRONMENT
 
  BEGIN_ENVIRONMENT
   '''System LRO/Sol'''
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   System '''LRO/Sol'''
 
   Date MJD 54892.2256944444
 
   Date MJD 54892.2256944444
 
  END_ENVIRONMENT
 
  END_ENVIRONMENT
 
 
''Launch Date''<br>
 
Although the launch is currently scheduled for 24th April 2009, the primary launch scenario provided in this add-on is the 27th April 2009 due to the mission constraints on the LAN of LRO's final Lunar orbit. The second launch scenario provided is for the 24th April 2009, should you wish to use it.
 
 
''Transx version''<br>
 
This document assumes the default Transx version supplied with Orbiter. Other versions may give different lunar intercept times.
 
 
 
'''QUICK INFO'''
 
 
''LRO''<br>
 
Final Lunar orbit - 30km x 70km, 90deg inclination(Equatorial), Periselene over South Pole,<br>
 
LAN = 38deg(Ecliptic) +/- 17deg(max.)
 
 
 
''LCROSS/AV020Centaur''<br>
 
Uses Lunar flyby to reach high-inclination Earth orbit,<br>
 
Spacecraft:Moon orbit resonance 2:3 (other resonances possible)
 
 
Impact chosen target at North Pole of Moon (targets designated by surface bases "Lcross_A" to "Lcross_E"),  impact speed ~2.5km/s, impact angle > 60deg.
 
 
Lcross separates from AV020Centaur at impact -9hrs. Lcross impact 4mins after AV020Centaur.
 
 
Impact should be timed to be visible by LRO passing over and by ground-based observers in Hawaii during hours of darkness.
 
 
== Procedures ==
 
Accuracy of burns in this mission is '''CRITICAL'''.
 
  
 
=== Launch ===
 
=== Launch ===
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  Click '''Set'''
 
  Click '''Set'''
 
  Click '''Tgt''' and enter '''Moon'''
 
  Click '''Tgt''' and enter '''Moon'''
  Click '''Nxt''' 6 times so that ''Off Plane'' is highlighted.
+
  Click '''Nxt''' 5 times so that ''Realtime'' is highlighted.  
Click '''+''' twice to change it to ''Source Plane''.
+
  Click '''+''' to change it to ''Off-Axis''.
Click '''Prv''' so that ''Realtime'' is higlighted.  
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  Click '''Nxt''' until the ''Tej'' parameter is highlighbted.
  Click '''+''' to change it to ''Off-Axis''
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  Click '''+''' or '''-''' repeately until the ''dV'' parameter reaches a minimum. This should be about ''3.3k''
Click '''Prv''' twice so that ''TIn'' is highlighted.
 
  Click '''+''' or '''-''' repeatedly to minimize the value of ''PlC'' in the lower left section of the MFD.
 
You may want to click on '''ADJ''' and set it to ''10x'' for this adjustment.
 
Be sure to set it back to ''1x'' when finished.
 
Click '''Prv''' twice so the ''Tej'' parameter is highlighted.
 
  Click '''+''' or '''-''' repeatedly until the ''EjA'' parameter is about 3 degrees.
 
If you go much below 3 degrees the ''Off-Axis'' parameter will change back to ''Realtime'',
 
and we need to be in ''Off-Axis'' mode.  
 
The ''dV'' parameter should be about ''3.15k'' at this point.
 
 
Select IMFD in the right MFD also.  
 
Select IMFD in the right MFD also.  
 
  Click '''MNU''', then '''PG'''. Enter '''0''' for the ''MFD ID''. Click '''Map'''.
 
  Click '''MNU''', then '''PG'''. Enter '''0''' for the ''MFD ID''. Click '''Map'''.
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  Click '''MOD''' 3 times, then click '''Nxt''' so that ''Accuracy'' is highlighted.  
 
  Click '''MOD''' 3 times, then click '''Nxt''' so that ''Accuracy'' is highlighted.  
 
  Click '''-''' twice so that ''accuracy'' is set to ''Max''.
 
  Click '''-''' twice so that ''accuracy'' is set to ''Max''.
  Click '''MOD''' twice to return to the map display with equatorial parameters.
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  Click '''MOD''' to return to the map display.
Wait until the ''TEj'' parameter in the left display is ''1k'' or less.
+
Wait until the ''TEj'' parameter in the left display is ''1k''
 
  In the left MFD, Click '''MOD''', and ''Offset Disabled'' should be highlighted.  
 
  In the left MFD, Click '''MOD''', and ''Offset Disabled'' should be highlighted.  
 
  Click '''+''' twice and ''Vel. Frame'' should be displayed. Click '''Nxt''' until ''Lon'' is highlighted.  
 
  Click '''+''' twice and ''Vel. Frame'' should be displayed. Click '''Nxt''' until ''Lon'' is highlighted.  
  Click '''Set''' and enter '''65'''. Click '''Nxt''' and ''Lat'' should be highlighted.  
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  Click '''Set''' and enter '''86.7'''. Click '''Nxt''' and ''Lat'' should be highlighted.  
  Click '''Set''' and enter '''-59.8'''. Click '''Nxt''', then '''Set''', and enter '''20.3M''' for ''Rad''.  
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  Click '''Set''' and enter '''27.6'''. Click '''Nxt''', then '''Set''', and enter '''12.79M''' for ''Rad''.  
  Adjust the ''Rad'' and ''Lat'' parameters to get the ''PeA'' and ''EqI'' parameters in the right MFD as close
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  Adjust the ''Rad'' and ''Lat'' parameters to get the ''PeA'' and ''Rin'' parameters in the right MFD as close
  as possible to ''350k'' and ''90'' degrees. Repeat as necessary. Click '''Pg''', then '''BV''', then '''AB'''.
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  as possible to ''216k'' and ''90'' degrees. Repeat as necessary. Click '''Pg''', then '''BV''', then '''AB'''.
 
  Disengage the ''Prograde'' autopilot.
 
  Disengage the ''Prograde'' autopilot.
  
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=== Lunar targeting/LCROSS ===
 
=== Lunar targeting/LCROSS ===
 
* Swingby of moon is passive (no thrusting)
 
* Swingby of moon is passive (no thrusting)
* 84 days in post-swingby cruise orbit
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* 81 days in post-swingby cruise orbit
* Current baseline is a '''3 Lunar orbit:2 Spacecraft orbit''' trajectory with north pole impact
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* Current baseline is 3-month trajectory with north pole impact
* Two revolutions in high ecliptic inclination (~50 deg), 42-day period Earth orbit
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* Two revolutions in high ecliptic inclination (~50 deg), 40-day period Earth orbit
  
 
When you reach 32M altitude above the Earth, the Centaur engine will automatically purge of all fuel and control switches over to the LCROSS propulsion system. You may initate the engine purge manually by pressing '''B'''. It is '''critical''' that you get your targeting done for LCROSS before this time, as once that happens, your deltaV budget is severely limited.
 
When you reach 32M altitude above the Earth, the Centaur engine will automatically purge of all fuel and control switches over to the LCROSS propulsion system. You may initate the engine purge manually by pressing '''B'''. It is '''critical''' that you get your targeting done for LCROSS before this time, as once that happens, your deltaV budget is severely limited.
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  Click '''+''', then '''Nxt''' four times until ''Delta Velocity'' is highlighted.  
 
  Click '''+''', then '''Nxt''' four times until ''Delta Velocity'' is highlighted.  
 
  Click '''Set'''. Click '''TGT''', and type '''Moon'''.
 
  Click '''Set'''. Click '''TGT''', and type '''Moon'''.
  Click '''Nxt''', then '''Set''', and set ''TEj'' to '''400'''.
+
  Click '''Nxt''' four times until ''dVf'' is highlighted.  
Click '''Nxt''' three times until ''dVf'' is highlighted.  
 
 
  Click '''Set''', and enter '''0'''.
 
  Click '''Set''', and enter '''0'''.
 
  in the Right MFD, click '''Plan''' so the green course line turns blue.
 
  in the Right MFD, click '''Plan''' so the green course line turns blue.
 
  In the left MFD, adjust ''dVp'' and ''dVf'' so that ''RIn'' and ''PeA'' in the right MFD
 
  In the left MFD, adjust ''dVp'' and ''dVf'' so that ''RIn'' and ''PeA'' in the right MFD
  are as close as possible to ''90'' degrees, and ''1.5M'', respectively.
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  are as close as possible to ''90'' degrees, and ''2.5M'', respectively.
Click '''Prv''' until ''TEj'' is highlighted and set it to '''0'''.
 
 
  Click '''PG''', '''BV''', and '''AB'''.
 
  Click '''PG''', '''BV''', and '''AB'''.
 
  When the burn is finished, click '''BV''', and '''PG''' in the left MFD, and '''Plan''' in the right MFD.
 
  When the burn is finished, click '''BV''', and '''PG''' in the left MFD, and '''Plan''' in the right MFD.
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There will be a green line extending from the center of the moon to hopefully past the edge. This is an edge-on view of our current approach to the moon.
 
There will be a green line extending from the center of the moon to hopefully past the edge. This is an edge-on view of our current approach to the moon.
We need to fine tune this approach to give us a lunar gravity assist which will result in a highly inclined orbit around the earth with a period of 42 days
+
We need to fine tune this approach to give us a lunar gravity assist which will result in a highly inclined orbit around the earth with a period of 40 days
  
 
  On the Right MFD, click the '''VAR''' button twice to bring up the ''Inc. angle'' parameter
 
  On the Right MFD, click the '''VAR''' button twice to bring up the ''Inc. angle'' parameter
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  on the solid green line in the slingshot view.
 
  on the solid green line in the slingshot view.
  
This is our current trajectory. Now we need to adjust the trajectory to impact the moon in 2 orbits with a 42 day period.
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This is our current trajectory. Now we need to adjust the trajectory to impact the moon in 2 orbits with a 40 day period.
 
  Note the angle of this line. We will be adjusting the length of the line,
 
  Note the angle of this line. We will be adjusting the length of the line,
 
  but the angle '''must''' remain the same so that our flight path
 
  but the angle '''must''' remain the same so that our flight path
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  Click '''++''' 4 times so that the ''Orbits to Icept'' parameter is 2.0
 
  Click '''++''' 4 times so that the ''Orbits to Icept'' parameter is 2.0
  
Now we must figure out what our ''Enc. MJD'' should be. Take the current MJD and add 88.5 to it. (4.5 days to reach the moon, then 2 orbits of 42 days each.) For the 27 April(UTC) launch this would be 54948.2 + 88.5 = 55036.7 . This is the ''Enc. MJD'' we will be shooting for.
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Now we must figure out what our ''Enc. MJD'' should be. Take the current MJD and add 85 to it. (5 days to reach the moon, then 2 orbits of 40 days each.) For the Mar 2 (UTC) launch this would be 54892 + 85 = 54977. This is the ''Enc. MJD'' we will be shooting for.
  
 
  Click '''VW''' again in the right MFD to get back to ''sling direct'' view.
 
  Click '''VW''' again in the right MFD to get back to ''sling direct'' view.
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My current solution is Inc Angle of 110.99 degrees and Outward angle of -38.1864. Enc MJD is 55036.6951, and Cl. App is 6.726M<br>
 
My current solution is Inc Angle of 110.99 degrees and Outward angle of -38.1864. Enc MJD is 55036.6951, and Cl. App is 6.726M<br>
 
Your Mileage may vary.
 
Your Mileage may vary.
 
[[Image:Lcrtgt2.jpg|frame|left|Transx Stage 2]][[Image:Lcrtgt3.jpg|frame|right|Transx stage 3]]
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
  Once a solution has been reached, click '''BCK''' twice on the Right MFD.  
 
  Once a solution has been reached, click '''BCK''' twice on the Right MFD.  
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  closer to the moon.
 
  closer to the moon.
  
== See also ==
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== [[LRO_part_2]] ==
*[[Lunar Reconnaissance Orbiter]]
 
*[[Lunar Reconnaissance Orbiter part 2]]
 
 
 
[[Category:Articles]]
 
[[Category:Orbiter 2010 add-ons]]
 
[[Category:Spacecraft add-ons]]
 
[[Category:Add-ons by BrianJ]]
 
[[Category:Tutorials]]
 

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