Orbital Express

 2007-006A

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Autonomous Space Transporter and Robotic Orbiter (ASTRO).

STP DARPA-0001 Orbital Express Adv Tech Demo, STP 2000. Launch in 2006 Sep by Atlas V 401 AV-013 from CC

2 sats launched in 2006 for auto docking and fuel transfer. Astro is the servicing and 'chase' spacecraft.

Orbit 492 x 492 x 46.

Mass 1100 kg, length 1.8m dia 1.8m and span 5.6m. Boeing Phantom Works, Advanced Systems is prime, DARPA is lead. Oct prism + 2 panels + manipulator arm.

After launch, ASTRO had some control problems and Nextsat managed the stack; the problems were sorted out by a software update on Mar 23.

After initial experiments culminating in undock and redock, there will be more tests with grapple capture of Nextsat and then seven rendezvous and capture tests and ranges up to 7 km, with further propellant transfers.

Date	Time	Event	Orbit
2007 Mar 9	0310	Launch by Atlas V
		T+4:04 Atlas MECO
		T+4:10 Atlas sep
	0314	T+4:20 Centaur MES-1
		T+4:28 Fairing sep
	0324	T+14:23 Centaur MECO-1	492 x 496 x 46
	0328	T+18:02 Orbital Express sep
2007 Mar		1 week checkout phase
2007 Mar 14		Checkout and initialization complete
2007 Mar 23		Software update solves GNC issue
2007 Mar 28		MDA checkout
2007 Apr 1		Propellant transfer expt
2007 Apr 2		Propellant transfer expt
2007 Apr 5		Prop transfer back from Nextsat
2007 Apr 6		Battery transfer via arm
		Battery installed on NextSat
2007 Apr 9		Prop transfer to N
2007 Apr 11		Prop transfer to N
2007 Apr 13		Prop transfer from N
		Prop coupler demate
2007 Apr 17
		MDA unberth Nextsat, position at 2m distance
	1754	Separation ring ejected
		Reberth Nextsat
2007 May 6
	0522	Undock from Nextsat
		Sep to 10-m
	0630?	Redock Nextsat after 1 hr
2007 May 11		Undock from Nextsat
		Scenario 3-1
		Stationkeep at 10m on way to 30m
		At 30 m
		Return to 10m
		Computer problem, guidance abort
		Retreat towards 120m
		Guidance issues, drift to 2.5km behind for 24 h
2007 May 12		Software issue, burn incorrect
		End up 6 km ahead of NextSat
2007 May 19		Redock with Nextsat
2007 Jun 16	0950	Undock, sep to 120m
		Flyaround; Scenario 5
		Stationkeep for 17 min
		-R-bar approach
		Redocked after 5 hr?
2007 Jun 23		Undock; Scenario 7
		Stationkeep at 4 km
2007 Jun 23		Capture Nextsat with MDA arm
2007 Jun 29?		Undock to 7 km; Scenario 8
2007 Jun 29		Redock
2007 Jul 2		Propellant transfer; complete Sc. 8
2007 Jul 16		EOL scenario: undock
		Separate to 310 km range
		Begin re-rendezvous
2007 Jul 19		Rendezvous with Nextsat
		Stationkeep at 1 km
2007 Jul 20		Separation burn
2007 Jul 21		Nextsat turned off
2007 Jul 22		Astro fuel jettison
		Astro deactivated

Payload:

• Manipulator arm (MDA)

• AVGS guidance sensor (MSFC) for capture

• ARCSS (Autonomous Rendezvous and Capture Sensor System) for acquisition and approach; Laser rangefinder, vis, LWIR sensors, spotlight

• Docking capture system

• Crosslink antenna

• Battery ORU, 24 kg, for transfer to NS

• Computer ORU with firewire connection

2007-006C

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Ball STP Orbital Express target satellite, to be serviced by the Astro refuelling satellite. Mass 250 kg (or 400 kg?).

Oct Cyl + 1 panel.

Ball Aerospace provided the Next Generation Satellite and Commodities spacecraft (NextSat/CSC) and ground support equipment, and participated in launch and mission operations.

Payload:

• Servicable propellant system with hydrazine (no propulsion system)

• Crosslink antenna

• Docking targets

• ORU fixture

• Grapple fixture

IRS-1C

 1995-072A

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IRS-1C was the first of an improved generation of IRS satellites, placed in a 10:30 local time sun-synchronous orbit. Mass was 1350 kg launch, 1250 kg on orbit. This was the first launch by a Molniya 8K78M into sun-synchronous orbit; the Blok-I stage was suborbital and the Blok-2BL fourth stage fired to circularize the orbit. Bus was 1.6 x 1.6 x 1.1m with solar panel span about 12m?

IRS-1C
Date	Time	Event	Orbit
1995 Dec 28	0645:18	Launch by Molniya 8K78M	KB LC31
	0647:18	Blok-BVGD sep. 60 km (T+2:00)
	0648:57	Fairing sep, 210 km (T+3:39)
	0649:21	Blok A sep, 252 km (T+4:02)
	0653:24	Blok I sep, 604 km (T+8:05)	-4487 x 803 x 97.94
	0656:40	BOZ ignition, (T+11:21)
	0657	Blok 2BL ignition
	0657:20	BOZ separation, 2BL at 0.75 thrust, 798 km (T+12:01)
	0700:12	Blok 2BL cutoff (T+14:53), 804 km
	0700:19	Blok 2BL sep (T+15:01)	101.1 805 x 817 x 98.6
	0707?	Blok I reentry, Arabian Sea off Somali coast?
	0710:20	Blok 2BL deorbit
1996 Jan 1		Orbit raise	816 x 818 km x 98.6
1996 Jan 5		Cameras switched on
2009 Sep 21		End of operations

How to Teach Filthy Rich Girls

https://welib.org/md5/0319eb62d6c1f4f702b1b35277815af0

WIRE

 1999-011A

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The Wide Field IR Explorer (WIRE) is SMEX 5. PI was Perry Hacking of JPL. The cryogenically cooled satellite would carry out IR studies of galaxy formation. The telescope had a 33 arcmin FOV and 12 and 25 micron detectors, with 20 arcsec resolution. It will survey 1000 square deg. Spacecraft mass is 187 kg. The Lockheed Martin cryostat is cooled to 6.5K by solid hydrogen. The spacecraft uses the GSFC SMEX bus with an octagonal structure.

WIRE was launched by a Pegasus rocket from Vandenberg. The Pegasus was successful, although a guidance anomaly caused delays to the next Pegasus flight. WIRE was deployed in a 539 x 593 km x 97.5 deg sun-synchronous orbit.

Unfortunately, the telescope cover was ejected shortly after orbit injection (instead of 3 days later), before the satellite was stabilized. Earthlight entering the aperture boiled off hydrogen, sending the spacecraft tumbling at 1 rev per second. For several days battery power decreased and the hydrogen vented, with the last hydrogen depleted in a few days. The spin was controlled by Mar 12.

The failure investigation reported that a circuit in the satellite's power system surged when it was switched on, and triggered the explosive bolts on the cover.

After the tumbling craft was brought back under control it seemed that it could only be used for engineering tests. Then Derek Buzasi of Berkeley realized that WIRE's star tracker, designed to point the observatory at its targets, was itself a useful optical space telescope. With only a 2-inch aperture, the F/1.8 telescope poses no challenge to Hubble, but its CCD detector can take low resolution images ten times a second and has remarkable photometric accuracy. WIRE's star tracker can measure a bright (0-2mag) star to within a millimagnitude in each exposure, and Buzasi is interested in studying small amplitude oscillations in convective stars, something WIRE's tiny space telescope can do more efficiently than a large ground based telescope like Keck. On April 30 WIRE was turned to observe Procyon as a test target, and followed up with the Ap star Gamma Aquilae, confirming its known variations. A long look at Regulus confirmed its constancy to a few micromagnitudes, showing that WIRE's observations were reliable. The main science program started in May with the target Alpha Ursae Majoris. Operations continued until funding ended in Sep 2000; a second cycle of observations began in 2003 and was concluded in 2008.

WIRE
Date	Time	Event	Orbit
1999 Mar 1	0155	L-1011 T/O from VAFB
	0256	Abort at T-45s, fin pin problem
	0324	L-1011 landed at VAFB
1999 Mar 5	0155	L-1011 T/O from VAFB
	0255:55	Launch from L-1011
		T+0:05 St 1 burn
		T+1:15 St 1 burnout
		T+1:31 St 2 burn
		T+2:06 Fairing
		T+2:43 St 2 burnout
	0307:29	T+7:34 St 3 burn 68s
	0308:37	T+8:42? St 3 burnout
	0309:37?	T+9:42? St 3 sep
	0327	Cryo cover ejected prematurely
		Venting H
1999 Mar 8		Cryo depleted	95.99 539 x 593 x 97.5
1999 Mar 12		Spacecraft stable in safemode
1999 Apr 30		Star camera observations begin
2000 Sep 30		Star camera operations suspended
2003 Nov 26		Star camera operations resume
2003 Dec 16		Observing program begins
2004 Jan		Control to Bowie State, MD
2008 Mar?		End of operations

Payload:

• Solid hydrogen cryostat.

• Telescope, Ritchey-Chretien 0.30m.

• Focal plane arrays, 12 and 25 mu, 128 x 128 pixels

In the Shadow of the Moon

https://welib.org/md5/80060ab46840dd489cbc51338bebe007