International Sun-Earth Explorer Unmanned Spaceflight

Comet Giacobini-Zinner gets ICEd

The International Cometary Explorer satellite – originally launched as International Sun-Earth Explorer 3 in 1978 – reaches the culmination of a series of complex orbital changes: a flyby of Comet Giacobini-Zinner, within 5,000 miles of the nucleus, primarily to sample and study the comet’s plasma tail and the interaction between that and the solar wind. …

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Pioneer Unmanned Spaceflight

Pioneer Venus captures Halley’s Comet

Having already conducted measuresment of Comets Encke and Giacobini-Zinner, the still-functioning Pioneer Venus Orbiter, launched in 1978, becomes the centerpiece of the American effort to gather close-up data on Halley’s Comet. Imaging the comet in ultraviolet light, Pioneer Venus captures Halley from a unique vantage point: both the comet and the planet being orbited by …

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Giotto Unmanned Spaceflight

Giotto gets close to Halley’s Comet

The European Space Agency’s unmanned Giotto space probe makes its closest approach to the nucleus of Halley’s Comet, coming within 400 miles of the comet’s core and taking unprecedented photos that help scientists refine their theories about cometary composition and formation. Giotto pays for the close encounter by taking a beating: its instruments register significant …

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Galileo Hubble Space Telescope Science & Technology Unmanned Spaceflight Voyager

Jupiter eats a comet

Its collision with the solar system’s largest planet predicted over a year in advance, the fragments of Comet Shoemaker-Levy 9 begin impacting Jupiter’s atmosphere in an astronomical event lasting six days. With Earth-based telescopes watching, as well as cameras and instruments on the Hubble Space Telescope, Galileo and even Voyager 2, huge explosions are witnessed …

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Rosetta / Philae Unmanned Spaceflight

Philae: first soft landing on a comet

Launched in 2004, the European Space Agency’s Rosetta space probe, orbiting Comet 67P/Churyumov-Gerasimenko in the outer solar system, releases the Philae robotic lander to descend to 67P’s surface. The lander’s harpoon anchoring system doesn’t work entirely as expected, and Philae bounces off the surface and goes spaceborne again for two hours before coming to rest …

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