Yahoo – AFP,
Mariette le Roux, 15 Nov. 2014
Paris (AFP)
- Robot probe Philae uploaded a slew of last-minute data to Earth from a comet
in deep space, before going to sleep at the end of its historic mission, ground
controllers said.
Data
streamed in as soon as Europe's pioneering robot lab reestablished late-night
contact with its orbiting mothership, Rosetta, but its limited battery soon
started wavering.
"My
#lifeonacomet has just begun," said an official tweet in the name of the
washing machine-sized lander perched on comet 67P/Churyumov-Gerasimenko since
Wednesday -- concluding with a restful "zzzzz".
European
Space Agency (ESA) photo
on November 13, 2014 shows an image
taken by Rosetta's
lander Philae (AFP
Photo)
|
The
European Space Agency (ESA) said its robot lab had entered "idle
mode", with all instruments and most systems shut down after three days of
non-stop work -- taking pictures and probing the comet's density, temperature,
composition and atmosphere.
"Prior
to falling silent, the lander was able to transmit all science data
gathered," said a statement.
The lander
and its mothership, which relayed Philae's data to Earth, had only two
communications windows per day -- the last opened around 2130 GMT on Friday and
closed at 0036 GMT the next morning as Rosetta disappeared in orbit behind the
comet.
Mission
controllers had feared the robot may not even have enough power to make contact
during this window -- but they were pleasantly surprised.
"Science
from an alien world" ESA Operations tweeted when contact was made.
"Info now flowing from ."
The channel
should open again around 1000 GMT Saturday, but lander manager Stephan Ulamec
told AFP from mission control in Darmstadt, Germany, he did "not really
expect" contact with Philae then.
"The
chances that we could reestablish the link again tomorrow are really very, very
low," he said.
"The
battery is not completely empty, but it is below the level the central computer
needs to boot" up.
In one of
many jaw-dropping achievements, the robot lab appears to have lifted itself
slightly on Friday and rotate the larger of its solar panels to absorb as much
energy as possible to be stored for a possible wakeup later.
Philae had
landed in a dark ditch after a bouncy touchdown Wednesday, and did not get
enough sunlight to recharge its batteries sufficiently to extend its mission.
Mission
engineers dream, however, of making contact with the lander "at some
point" in the coming months as the comet, with Philae hopefully still
clinging to its surface, moves closer to the Sun.
Philae's
historic on-site survey of a comet travelling at 18 kilometres (11 miles) per
second, currently at a distance of 510 million kilometres (320 million miles)
from Earth, is the highlight in a more than decade-long mission.
Philae
landed Wednesday after a nail-biting seven-hour, 20-km descent from Rosetta,
which had travelled more than a decade and 6.5 billion kilometres (four billion
miles) to meet up with the comet in August this year.
The
touchdown did not go entirely as planned, when Philae's duo of anchoring
harpoons failed to deploy and it lifted off again... twice.
The lander
finally settled in a crevice in a location that remains a mystery, and data
revealed it was shadowed from sunlight that could have extended its core,
battery-powered mission of 60-odd hours.
'First
comet drilling'
Among the
most anticipated data from Philae is chemical analysis of a drill sample which
scientists hope will shed light on the origins of the Solar System 4.6 billion
years ago, and maybe even life on Earth.
The ESA
confirmed that Philae had drilled Friday, though it did not specify whether a
sample had been obtained.
"I
confirm that my (drill) went all the way DOWN and UP again!!" said a tweet
in the robot's name. "First comet drilling is a fact!"
The
Rosetta-Philae team said Friday they were ecstatic with the results.
"We're
in the middle of drinking champagne because this mission is a success," Philippe
Gaudon, the head of the Rosetta project at France's space studies centre CNES,
told AFP early on Saturday.
All 10
instruments on board the 100-kilogramme (22-pound) lab had kicked into action.
"This
machine performed magnificently under tough conditions, and we can be fully
proud of the incredible scientific success Philae has delivered," said
Ulamec.
The
1.3-billion-euro ($1.6-billion) mission aims to unlock the secrets of comets,
which some astrophysicists believe may have "seeded" Earth with some
of the ingredients for life.
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.