Vanguard 1

60th anniversary of solar power in space

Matthew Jeppesen

Proa Analytics

@matthewjeppesen

Silicon PV cells1954

Bell laboratories

1955

NavyAirforceArmy Signal Corps “Project Lunchbox” (solar)

Competing US designs

“the roofs of all our buildings in cities and towns equipped with solar cells would be sufficient to produce this country’s entire demand for electrical power” Dr Hans Ziegler, US Signal Corp

First satellites – Soviet

Sputnik 1Oct 1957

Sputnik 2Nov 1957

Radio transmissions

Sputnik 1 & 2

20 & 40 MHz

Chemical batteries ~ 20 days

Roy Welch, W0SLDallas NewsOct 1957

Vanguard test failure

December 1958

“Blow to US prestige”

“Kaputnik” Daily Express“Stay-Putnik” News Chronicle“Puffnik” Daily Mail

1.5 kg

16 cm diameter (76 cm antennas)

Outside and inside thermometers

2 radio transmitters108.0 MHz – battery108.3 MHz – solar

6 solar cells ~ 1 watt

Vanguard

MinitrackRadio and optical satellite trackingUS, Spain, Japan, India, Peru, Iran, Curaçao, Argentina, Australia

Feb 1958Universal newsreel

Success – Explorer 1

“SUCCESS”

Vanguard

“SOLAR UNIT FUNCTIONING”

Solar in space today

International Space Station 84 kW

CuriosityMars rover

Vanguard’s legacy

Proved suitability of solar power for space

6 years (23,000 orbits) of radio broadcasts

Improved understanding of earth shape, island locations

600 to 4,000 km altitude8 km per second

Oldest object made by humans in space

Satflare n2yoRecording (Roy Welch)

Thank youReferences and acknowledgements

C McLaughlin Green & M Lomask, Vanguard – A History, NASA, 1970

J Perlin, From space to earth: the story of solar electricity, Harvard 2002

US Naval Research Laboratory

US National Archives

New York Times archive

Susan Strange, Historian

Roy Welch, radio operator W0SL

Matthew JeppesenProa Analytics@matthewjeppesen

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