Sunday, January 1, 2017

Akatsuki

 2010-020D


Akatsuki (Dawn, Daybreak), Planet C is a Venus Climate Orbiter. Studies the distribution of clouds, trace gases, lightning discharges, and temperature, as well as plasma measurements and a search for active volcanism.

Mass 480 kg at launch.

320 kg prop? in 300 x 79000 km retrograde equatorial orbit. Box + 2 panels.

Box 1.04 x 1.45 x 1.40m. AOCS has 500N NTO/N2H4 thruster and 23N and 3N attitude thrusters.

HIIA 202 with 4m fairing. Launch provider is MHI with JAXA as range control.

Type 2 trajectory with 107.5 x 155.2 Mkm orbit.

Unfortunately Venus orbit insertion failed with damage to the insertion engine, and Planet C sailed on past in solar orbit. The post encounter orbit reported in Dec 2010 is 90 x 110 Mkm with 203d period.

puranetto c - Planet C kanaboshi tansaki - Venus probe

The OME test burns in Sep 2011 showed that the engine was severely damaged and could only generate small amounts of thrust. JAXA will dump all remaining 64 kg of oxidizer to reduce mass and then eventually perform VOI on monoprop RCS alone (4 x 23N).

As of early 2015, the plan was for VOI on 2015 Dec 7 into a 300 x 300000 - 400000 km orbit.


VCO 
 

DateTimeEventOrbit  

2010 May 20  2158:22 Launch by HIIA 202 F17 YoLP1 
  Az 93 deg 
 2200 T+2:05 SRB-A jettison 
  T+4:25 Fairing sep
  T+6:36 St 1 MECO 
  T+6:44 St 1 sep 223 km 5.5 km/s 
  T+6:50 SES-1 
 2209:51 T+11:29 SECO-1  300 x 300 x 30.0 
  J-POD ejects WASEDA, Negai, KSAT 
 2210:54 T+12:32 NEGAI* sep
 2211:04 T+12:42 Waseda-Sat2 sep
 2211:14 T+12:52 KSAT sep
 2220:54 T+22:32 Stage 2 MES-2 3:51 
 2224:45 T+26:23 Stage 2 MECO-2, solar orbit 
 2225:49 T+27:27 PLANET C sep 407 km to 478 km 11.7 km/s 
  Deploy solar arrays 
 2234:09 T+35:47 PAF900M Payload attach fitting sep 
 2241:04 T+42:42 Ikaros sep 
 2246:14 T+47:52 Unitec-1 sep 
2010 May 21  0100  C3=18.46  298 x -56249 x 31.47  
 0600  Pass EL1:4 
2010 May 21  2000  Pass lunar orbit 
2010 May 23  0840  Leave Earth SOI  0.717 x 1.066 AU x 2.02 
2010 May 24  1810  Leave Earth Hill sphere 
2010 May 25    307.22d 0.716 x 1.066 AU x 2.03 
2010 Jun 28   500N thruster test 13s 12m/s 
2010 Jul 1    307.78d 0.719 x 1.066 AU x 2.03 
2010 Nov 8   RCS-1 approach tweak 
2010 Nov 22   RCS-2 approach tweak 
2010 Dec 1   RCS-3 approach tweak 
2010 Dec 1    309.69 0.719 x 1.073 AU x 2.01 
2010 Dec 3  1859  Enter V sphere 1.008Mkm  700 x -73500 
2010 Dec 6  2349:00 VOI burn 
 2351:38 S+2:32 Burn aborted, Venus flyby 
2010 Dec 10  1307  Depart V sphere  700 x -88760  
2011 Apr 17  Perihelion 1 0.6 AU x 0.72? AU 
2011 Sep 7  0250 2s OME test burn, failed (13 pc thrust) 
2011 Sep 14  0250 OME test burn, 5s, failed 
2011 Sep 30  0302  DOX test 60s 1.9m/s 
2011 Oct 6  0253 Oxidizer dump 360s 65 kg total, DOX1 7.6m/s 
2011 Oct 12  0323 Oxidizer dump 540s DOX2 8.1m/s 
2011 Oct 13  0453 Oxidizer dump 540s DOX3 8.1m/s  
2011 Nov 1  0422 DV1 RCS burn 587s 88.6m/s 
2011 Nov   Perihelion 2, T=203d 
2011 Nov 10  0437 RCS DV-2 dV 544s 90.6m/s 
2011 Nov 21  0457 RCS DV-3 342s 63.5m/s 
  Total aphelion reduction 3M km  
2012 Mar 9    0.611 x 0.722 AU x 3.5 deg 
2012 Jun   Perihelion 3, T=199d?  
2015 Jul 17   DV4-1 
2015 Jul 24   DV4-2 
2015 Jul 31   DV4-3 Total 87m/s 
2015 Aug 30   Perihelion 
2015 Nov 13   3 Mkm from Venus 
2015 Dec 1 0820  Enter Venus sphere(L1) 
2015 Dec 6   Attitude change for VOI 
 2351:29  Enter Venus shadow, begin burn 20:28  
2015 Dec 7  0000  Periapsis 
2015 Dec 7   VOI-R1,  
 0011:57 End burn 
 0230  Exit shadow? period 13d14h  400 x 440000 x 3 
2015 Dec 20   Orbit adjust 1000? x 360000 10.5 days 
2016 Jan 31  1136  At 91000 km 
 1336  At 76000 km 
2016 Feb 20  Comms problem 
2016 Apr 4   Orbit tweak to delay eclipses 
2016 Apr 4  0728  Orbit adjust 4 of 8 thrusters, 15s burn  10.8d ? x 370000  

Payload:

  • IR1 NIR camera 1 1.0mu

  • IR2 NIR camera 2 1.7-2.4mu

  • LIR LWIR camera 9-11 mu

  • UVI UV imager 2800-3600A

  • LAC Lightning/Airglow camera 5510/5580/7770A

  • USO Ultrastable oscillator

  • EUV scanner 530-1300A

  • Ion/electron particle analysers

  • Magnetometer/Wave analysers 10 MHz

  • Orbit maneuver engine 500N (new Si3N4 silicon nitride design)

No comments:

Post a Comment

November 20,2006

  https://en.wikipedia.org/wiki/Association_football