August 6, 2014
SUCCESS! Rosetta Makes History By Rendezvousing With Comet 67P
redOrbit Staff & Wire Reports - Your Universe Online
Following a decade-long journey that spanned more than six billion kilometers through space, the ESA’s Rosetta probe has arrived at comet 67P/Churyumov-Gerasimenko, officially making it the first mission to ever successfully complete such a rendezvous.
The successful completion of the missions opens “a new chapter in Solar System exploration,” the agency said in a statement.
[ Watch: Rosetta: Science On The Comet ]
“After ten years, five months and four days traveling towards our destination, looping around the Sun five times and clocking up 6.4 billion kilometers, we are delighted to announce finally ‘we are here’,” added ESA Director General Jean-Jacques Dordain. “Europe’s Rosetta is now the first spacecraft in history to rendezvous with a comet, a major highlight in exploring our origins. Discoveries can start.”
As it made its final approach, Rosetta completed the last of 10 thruster firings that had been scheduled to take place over a span of several months, allowing it to slow down to a pace equivalent to a person walking, explained Kenneth Chang of the New York Times. Upon its arrival, the orbiter was said to be traveling roughly two miles per hour relative to the speed of its target, and at a distance of approximately 60 miles.
That final burn was designed to help Rosetta “into the first leg of a series of triangular paths around the comet,” added Wall Street Journal reporter Gautam Naik. Each of those legs was expected to be roughly 100 km (62 miles) long and take between three and four days to complete, ultimately allowing the probe to not only study the comet up close and land a probe on the surface, but also allowing it to follow 67P around the sun – all of which will be astronomical firsts.
[ Watch: Rosetta: Philae’s Mission At Comet 67P ]
“Today’s achievement is a result of a huge international endeavor spanning several decades,” said Alvaro Giménez, ESA’s Director of Science and Robotic Exploration. “We have come an extraordinarily long way since the mission concept was first discussed in the late 1970s and approved in 1993, and now we are ready to open a treasure chest of scientific discovery that is destined to rewrite the textbooks on comets for even more decades to come.”
Currently, ESA officials report that both the comet and the orbiter are approximately 405 million km from Earth (roughly halfway between the orbits of Mars and Jupiter) and heading en route toward the inner Solar System at speeds of nearly 55,000 km per hour. Comet 67P is in an elliptical 6.5-year orbit which takes it from beyond Jupiter at its most distant to between the orbits of Mars and Earth at its closest to the sun.
An ESA project operated with some assistance from NASA, Rosetta will spend the next two years studying the comet’s environment as well as its nucleus. Earlier this month, it was revealed that the orbiter had already successfully taken the comet’s temperature for the first time, and had captured images of a coma surrounding the nucleus.
“The Rosetta mission is a significant test of Europe's spacefaring ambitions. Scientists had to plan the 10-year trip through the solar system in minute detail. Orbiting and landing on a comet, whose surface properties are largely unknown, is no easy task either,” Naik said. The WSJ reporter added that “more than scientific credibility is at stake,” since the undertaking reportedly cost the ESA more than $1.7 billion dollars.
Image 2 (below): Artist impression of ESA's Rosetta approaching comet 67P/Churyumov-Gerasimenko. The comet image was taken on 2 August 2014 by the spacecraft's navigation camera at a distance of about 500 km. Spacecraft and comet are not to scale. Credit: Spacecraft: ESA/ATG medialab; Comet image: ESA/Rosetta/NAVCAM