Europe creates space history, Philae lands on comet
BERLIN: The European Space Agency (ESA) landed a probe
on a comet on Wednesday, a first in space exploration and the climax of a
decade-long mission to get samples from what are the remnants of the birth of
Earth’s solar system.
The box-shaped 100-kg (220-pound) lander, named
Philae, touched down on schedule at about 1600 GMT after a seven-hour descent
from spacecraft Rosetta around half a billion kilometers (300 million miles)
Scientists hope that samples from the surface of
67P/Churyumov-Gerasimenko will help show how planets and life are created as
the rock and ice that make up the comet preserve organic molecules like a
Comets come from the formation of Earth’s
4.6-billion-year-old solar system. Scientists believe they may have brought
much of the water in Earth’s oceans. “We are ready to make science fiction a
science fact,” ESA director of human spaceflight and operations, Thomas Reiter,
said at the European Space Operations Centre in Germany before the landing.
Rosetta reached the comet, a roughly 3-by-5 km rock
discovered in 1969, in August after a journey of 6.4 billion km that took 10
years, five months and four days - a mission that cost close to 1.4 billion Euros
($1.8 billion). Rosetta is the first spacecraft to orbit a comet rather than
just flying past to take pictures.
Wednesday’s launch went ahead despite a problem with
the thruster that meant the probe had to rely mainly on its harpoons to stop it
bouncing back from the comet's surface.
The three-legged lander had to be released at exactly
the right time and speed because it cannot be controlled on its descent. On its
way down, Philae gathered data and images, which were relayed back to Earth.
Engineers designed the lander not knowing what type of
terrain they would find on the comet's surface. Rosetta has been taking
pictures of the comet and collecting samples from its atmosphere as it
approaches the sun, showing it is not as smooth as initially hoped, making
landing more tricky.
The surface is also more dusty than expected, limiting
light needed to charge its solar panels and power its instruments once its
batteries run out after two and a half days.