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Explorer 9

Explorer 9, known as S-56A before launch, was a NASA satellite which was launched in February 1961 to study the density and composition of the upper thermosphere and lower exosphere. It was a reflight of the failed Explorer S-56 mission, and consisted of a 7 kg (15 lb), 3.66 m (12.0 ft) balloon which was deployed into a medium Earth orbit. The mission…

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Apogee altitude
2,225 km (1,383 mi)
Bus
S-56
Contractor
Vought
COSPAR ID
1961-004A
Decay date
9 April 1964
Dimensions
3.66 m (12.0 ft) diameter

Topics to explore

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Overview

Spacecraft

Experiment

Launch

Mission results

Legacy

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Map overview Semantic statistics

Explorer 9

Nodes38
Edges37
Triples67
Avg. degree1.95
Density0.052632
Components1

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Explorer 9

Top relations

related to Launch · 18
Explorer 9 → Delta, Explorer, February, GMT, Harvard, It, Launch Area, MHz, Mylar, Power, SAO Baker-Nunn, Scout X-1, ST-4, The, Upon, Wallops Flight Facility, Wallops Island, WFF
related to Satellite Drag Atmospheric Density · 14
Explorer 9 → Accurate, April, Baker-Nunn, Because, Cambridge, Density, Earth's, Explorer, Jacchia, July, Massachusetts, Slowey, Smithsonian Astrophysical Observatory, This
related to Mission results · 9
Explorer 9 → April, Careful, Earth's, Explorer, It, Sun's, The, Wallops Island, With
Apogee altitude · 1
Explorer 9 → 2,225 km (1,383 mi)
Bus · 1
Explorer 9 → S-56
Contractor · 1
Explorer 9 → Vought
COSPAR ID · 1
Explorer 9 → 1961-004A
Decay date · 1
Explorer 9 → 9 April 1964
Dimensions · 1
Explorer 9 → 3.66 m (12.0 ft) diameter
Entered service · 1
Explorer 9 → 16 February 1961

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Important terminology

explorer density launch satellite orbit spacecraft mission launched air research 1961 drag atmospheric first exosphere wallops s-56 15 perigee nasa

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
Explorer 9Apogee altitude2,225 km (1,383 mi)1.00infobox
Explorer 9BusS-561.00infobox
Explorer 9ContractorVought1.00infobox
Explorer 9COSPAR ID1961-004A1.00infobox
Explorer 9Decay date9 April 19641.00infobox
Explorer 9Dimensions3.66 m (12.0 ft) diameter1.00infobox
Explorer 9Entered service16 February 19611.00infobox
Explorer 9Harvard designation1961 Delta 11.00infobox
Explorer 9Inclination38.91°1.00infobox
Explorer 9Launch date16 February 1961, 13:05:00 GMT1.00infobox
Explorer 9Launch mass7 kg (15 lb)1.00infobox
Explorer 9Launch siteWallops Flight Facility, LA-31.00infobox
Explorer 9ManufacturerLangley Research Center1.00infobox
Explorer 9Mission duration3 years (achieved)1.00infobox
Explorer 9Mission typeAir density research1.00infobox
Explorer 9NamesS-56A Explorer IX NASA S-56A1.00infobox
Explorer 9OperatorNASA1.00infobox
Explorer 9Perigee altitude545 km (339 mi)1.00infobox
Explorer 9Period118.6 minutes1.00infobox
Explorer 9Powersolar cells and rechargeable batteries1.00infobox
Explorer 9Reference systemGeocentric orbit1.00infobox
Explorer 9RegimeMedium Earth orbit1.00infobox
Explorer 9RocketScout X-1 (ST-4)1.00infobox
Explorer 9SATCAT no.000811.00infobox
Explorer 9SpacecraftExplorer IX1.00infobox
Explorer 9Spacecraft typeAir Density Explorer1.00infobox

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