Delta 5000

Delta 5000 series

Launch of the Delta 5920 withCOBE
Function	Expendable launch system
Country of origin	United States
Cost per launch	US$34.22 millionin 1985(US$79.99 millionin 2018)
Size
Height	34 m (112 ft)
Diameter	2.44 m (8 ft 0 in)
Mass	201,580 kg (444,410 lb)
Stages	2
Capacity
Payload toLEO
Mass	3,848 kg (8,483 lb)
Payload toGTO
Mass	1,405 kg (3,097 lb)
Associated rockets
Family	Delta
Comparable	Delta 4000,Delta II
Launch history
Status	Retired
Launch sites	VandenbergSLC-2W
Total launches	1
Success(es)	1
UTC date of spacecraft launch	18 November 1989
Boosters –Castor 4A
No. boosters	9
Height	9.12 m (29.9 ft)
Diameter	1.02 m (3 ft 4 in)
Empty mass	1,529 kg (3,371 lb)
Gross mass	11,743 kg (25,889 lb)
Powered by	Solid
Maximum thrust	478.3 kN (107,500 lbf)
Specific impulse	Sea level:237 seconds Vacuum:266 seconds
Burn time	56 s
First stage – Thor/Delta ELT
Height	22.37 m (73.4 ft)
Diameter	2.44 m (8 ft 0 in)
Empty mass	4,360 kg (9,610 lb)
Gross mass	84,368 kg (186,000 lb)
Powered by	1RS-27
Maximum thrust	1,030.2 kN (231,600 lbf)
Specific impulse	Sea level:262 seconds Vacuum:296 seconds
Burn time	223 s
Propellant	LOX/RP-1
Second stage –Delta K
Height	5.89 m (19.3 ft)
Diameter	2.44 m (8 ft 0 in)
Empty mass	950 kg (2,090 lb)
Gross mass	6,954 kg (15,331 lb)
Powered by	1AJ10-118K
Maximum thrust	43.6 kN (9,800 lbf)
Specific impulse	319 s
Burn time	431 s
Propellant	N2O4/Aerozine 50

TheDelta 5000 serieswas an Americanexpendable launch systemwhich was used to conduct anorbitallaunch in 1989. It was a member of theDeltafamily of rockets. Although several variants were put forward, only the Delta 5920 was launched. The designation used afour digit numerical codeto store information on the configuration of the rocket. It was built from a combination of spare parts left over from earlier Delta rockets, which were being retired, and parts from theDelta II6000-series, which was just entering service.

The first stage was theRS-27poweredExtended Long Tank Thor,flown on several earlier Delta rockets. NineCastor-4Asolid rocket boosterswere attached to increase thrust at lift-off, replacing the less powerfulCastor-4boosters used on the 3000 series. TheDelta-Kwas used as a second stage. In the configuration that was launched, no third stage was flown.

The Delta 5000 was launched just once, fromSpace Launch Complex 2Wat theVandenberg Air Force Base.Launch occurred at 14:34 on 18 November 1989. It was successful, and placed theCosmic Background Explorer(COBE) spacecraft intolow Earth orbit.

Payload

This section is an excerpt fromCosmic Background Explorer.[edit]

Artist's concept of the COBE spacecraft

TheCosmic Background Explorer(COBE/ˈkoʊbi/KOH-bee), also referred to as Explorer 66, was aNASAsatellite dedicated tocosmology,which operated from 1989 to 1993. Its goals were to investigate thecosmic microwave background radiation(CMB or CMBR) of theuniverseand provide measurements that would help shape our understanding of thecosmos.

COBE's measurements provided two key pieces of evidence that supported theBig Bangtheory of the universe: that the CMB has a near-perfectblack-bodyspectrum,and that it has very faintanisotropies.Two of COBE's principal investigators,George F. SmootandJohn C. Mather,received theNobel Prize in Physicsin 2006 for their work on the project. According to the Nobel Prize committee, "the COBE project can also be regarded as the starting point forcosmologyas a precision science ".

COBE was the second cosmic microwave background satellite, followingRELIKT-1,and was followed by two more advanced spacecraft: theWilkinson Microwave Anisotropy Probe(WMAP) operated from 2001 to 2010 and thePlanck spacecraftfrom 2009 to 2013.