Monday, April 10, 1995

Explorer 38

  1968-055A


The first Radio Astronomy Explorer, RAE 1, was built by Fairchild-Hiller Space System Div (Md) for NASA-GSFC. The satellite, RAE-A before launch, had four antennae deployed in a pair of V shapes. One pair of antennae were each 18m long, the second pair were 228m long. Explorer 38 was launched at 1727 on 1968 Jul 4 by a Delta J from Space Launch Complex 2-East at Vandenberg. It entered a parking orbit of 640 x 5994 km. The solid apogee motor fired on Jul 7 to change the orbit to 224.4 min, 5851 x 5861 km x 120.6 deg. On Jul 8 the satellite was despun and on Jul 22 the process of extending the antennae began. At first, the large antennae were extended only to 138m. On Sep 24 the antennae were extended to 183m, and operations with the radio astronomy experiment began on Sep 26. Final extension of the antennae to 228m (450m span) occurred on Oct 8. RAE I operated until 1972 Dec 25. In 1970 and 1971 some gravity gradient dynamics experiments were performed and on 1972 Oct 31 the spacecraft was rotated 180 degrees around its pitch axis. This allowed the previously earth-pointed vector to observe celestial emission.


RAE A 
 

DateTimeEventOrbit  

1968 Jul 4  1726:50  Launch by Delta J V SLC2E 
  T+0:43 SRM burnout 
  T+0:50 SRM sep 
  T+2:31 MECO  -6300 x 640 x 120.6 
  T+2:35 SES 
  T+2:46 Fairing 
  T+2:46 Inertia booms deploy 
 1735:54 T+9:04 SECO  -3570? x 645 x 120.6 
  T+11:03 St 2 sep   
  T+11:17 St 3 burn 44s 
 1738:49 T+11:59 St 3 burnout 
 1740:32 T+13:42 St 3 sep 640 x 5994 x 120.6 
 1747?  Stage 2 entry 
1968 Jul 7  0938 A+0 AKM burn   
 0938 A+0:18 AKM burnout  224.4 5851 x 5861 x 120.6 
 0940 A+2:00 AKM sep 
  Spin at 92 rpm 
1968 Jul 8  1630  Yo-yo despin 
1968 Jul 8   Magnetic despin  
1968 Jul 22  1702  Extend to 112 m 
  Extend to 138m 
1968 Jul 23  1510  Dipoles to 20 m 
1968 Sep 24   Extend to 183m 
 2031  Completed 
1968 Oct 8  1722 Extend to 229m 
 1917  Complete to 229m 
 1950  Libration damper extend from 165 to 192m 
1972 Oct 31   Inversion experiment 
 1500  Retract wires to 160m, 21 min 
 1521 70 min coast 
 1631 Extend to 229m, 14 min 
 1645 Extension complete 
 1645 Activated damper 
1972 Dec 25   End of ops 

No comments:

Post a Comment

These Are Not My Beautiful Stories

  Summary: The chapters within are outlines for both future stories I’ve got planned (in the case that I never get around to writing them) a...