International Military Discussion

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SaiK
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Re: International Military & Space Discussion

Post by SaiK »

well she replied:

sky-high ‏@saikanomie 43m43 minutes ago
@CathyFinch @esa @ESA_Rosetta @Philae2014 From where did you get this from? Can you please provide link to actual source?

Cathy Finch ‏@CathyFinch 20m20 minutes ago
@saikanomie The source was @NASAWatch
from @nasawatch I got this now:

http://www.bbc.com/news/science-environ ... ws_central

Image
This photo from Philae shows the surface during the lander's approach
Continue reading the main story
Related Stories

Probe may have 'landed twice' Watch
Can you land on a comet?
Rosetta: The story so far
A European robot probe has made the first, historic landing on a comet, but its status is uncertain after harpoons failed to anchor it to the surface.

Officials said the craft may have lifted off the comet after touchdown before returning to the surface.

Lander project manager Stephan Ulamec said: "Maybe we didn't just land once, we landed twice."

The European Space Agency's director general described the landing as "a big step for human civilisation".

Further analysis is needed to fully understand the status of the probe, known as Philae.

However, Dr Ulamec told the BBC that at last radio contact with the probe, he believed it to be in a stable configuration.

"This is the indication right now," he explained. "We really have to wait until tomorrow morning and then we will know a lot more."

The "first" landing on Comet 67P/Churyumov-Gerasimenko was confirmed at about 1605 GMT.

There were cheers and hugs at the European Space Agency (Esa) mission control in Darmstadt, Germany, after the signal came through.

Director general Jean-Jacques Dordain described it as "a great great day, not only for Esa, but... I think for the world".

Jump media playerMedia player helpOut of media player. Press enter to return or tab to continue.
The moment the Philae comet landing was confirmed
Early data started to come back from instruments, and one team could see that the lander had sunk about 4cm (1.5 inches) into the surface, suggesting a relatively soft top layer.

But shortly after, engineers could see that the harpoons, designed to fasten the spacecraft to the 4km-wide (2.5 miles) ball of ice and dust, had not fired as planned.
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Re: International Military & Space Discussion

Post by SaiK »

Philae from Rolis instrument
One of the cameras on Philae sent this image of the comet during the descentImage

super clarity!!!

Image
Philae's landing site was on the head of the 4km-wide rubber-duck-shaped comet

Mission facts:

Philae lander

Travelled 6.4 billion km (four billion miles) to reach the comet
Journey took 10 years
Planning for the journey began 25 years ago
Comet 67P

More than four billion years old
Mass of 10 billion tonnes
Hurtling through space at 18km/s (40,000mph)
Shaped like a rubber duck
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Re: International Military & Space Discussion

Post by SaiK »

SaiK
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Re: International Military & Space Discussion

Post by SaiK »

it appears there is a lot of desert dust on the comet !
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Re: International Military & Space Discussion

Post by Aditya_V »

Look at the postyive commentary of Rosetta vs the rubbish poverty commentary on ISRO. Plain racism.
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Re: International Military & Space Discussion

Post by SSSalvi »

^^^
Unfortunately for a common man both the missions are ' komet ka photo ' missions although for MOM it just happened to be an unexpected opportunity.

People expect that any camera should work for any photograph.

There is a retort by Priyanka Gupta: ' Try taking a picture from 1 lakh km from whatever camera you have and zoom it. '

It is the duty of ISRO to listen and clarify limitations and futility in comparison while publishing the images and after listening to vox populi.

But ISRO only have Cameras and no Ears :)

The image on their Facebook pages is not available on ISRO.org

Original 5 images given in the brochure are not available.
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Re: International Military & Space Discussion

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Last edited by SaiK on 14 Nov 2014 06:46, edited 1 time in total.
NRao
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Re: International Military & Space Discussion

Post by NRao »

Looks like the little critter bounced twice and as a result landed sideways (with one of three legs facing upwards) near a cliff. The cliff they say allows 90 minutes of sun light, posing another problem. The battery life is 60 hours and they had hoped to get a lot done before they lost that.

Wonder if they thought through such possibilities - especially the bounce. A small amount of fuel with proper thrusters may have helped. 20/20.
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Re: International Military & Space Discussion

Post by SaiK »

so without winds.. how are those sand formation like things happen?
low gravity and drift?

and I do see water/ice melt while near sun, wet when away from sun, frozen in a continuum. :mrgreen: just kidding.. but it does appear like river sand patterns.
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Re: International Military & Space Discussion

Post by SaiK »

http://video.foxnews.com/v/embed.js?id= ... =466&h=263
as usual fox khujli.. but they say it bounced thrice! and is slanted now
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Re: International Military & Space Discussion

Post by Singha »

BBC and CNN were in full psyops +ve mode after the landing. BBC infact had interrupted normal programming to cover it all...so bartania probably has a good number on the team.

in parallel NDTV under VSom was hosting a interview of ISRO top brass incl the chairman with some college and high school students. when asked how/when the youth of country could contribute to the space pgm, some vague answer was given when I felt the talking points should have been
- list out which univs ISRO is collaborating with for payloads and data analysis
- how many more such univs would be roped in for future
- how interested univs can apply for this program - the process, contacts, proposals, URL
- the size, current intake and curriculum of the ISRO run engineering college in Triv
- some examples of young isro scientists and what they are doing , a day in the life video, soothing interviews like google recruitment ads
- and finally an exhortation to youth to come up through various disciplines and join ISro, some info on perks, projects , payscales
if time was too short in the pgm, atleast prepare a webpage with all such data and point to it.

above is the gora +ve psyops approach. instead we got some vague answer.

ultimately its a battle for raw material talent and GOI never acts like it is serious in understanding and attracting people.
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Re: International Military & Space Discussion

Post by Victor »

NRao wrote:Looks like the little critter bounced twice and as a result landed sideways (with one of three legs facing upwards) near a cliff. The cliff they say allows 90 minutes of sun light, posing another problem. The battery life is 60 hours and they had hoped to get a lot done before they lost that.

Wonder if they thought through such possibilities - especially the bounce. A small amount of fuel with proper thrusters may have helped. 20/20.
Methinks what happened is when the harpoons were fired, the counter pressure thruster failed, so instead of the harpoon blasts securing Philae to the surface, they acted like thruster rockets and blasted the craft back into space. "Bounce" is a flip term for this in the rare atmosphere (almost zero) and if the blasts were a little more powerful, Philae could well have departed on an interstellar journey by itself. It was a lucky break but it doesn't take away from the awesomeness of the event.

Speaking of which, just saw Interstellar which has a very similar maneuver to Rosetta's which matched the spinning of comet 67P in order to land Philae on it. In the movie, the spaceplane pilot matched the spinning of a damaged space station in order to dock, then counter-rotated using his rockets to stabilize the station.
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Re: International Military & Space Discussion

Post by SaiK »

well, earlier they said the harpoons failed to fire. dunno what is true.
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Re: International Military & Space Discussion

Post by Victor »

^ One Frenchie was saying that the thruster failed and it was supposed to "push the lander against the comet". Obviously, this was to act in tandem with the harpoons to counteract their force. If the thruster fails and the harpoons fire, we have liftoff. In a way, the net result would be the harpoons "malfunctioning" I guess. The video at the end of this report shows what was supposed to happen with the thruster and harpoons firing together.
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Re: International Military & Space Discussion

Post by NRao »

The critter has no thrusters.

When it landed they had expected a soft landing, followed by the legs screwing themselves to the surface and the harpoons firing. No one know what exactly happened, but it did tweet (!!!!) that the harpoon did not fire. Two bounces later it landed awkwardly on its side - with one leg pointing into space (upward) - I think that was determined from the panoramic view it sent back (http://www.nasa.gov/sites/default/files ... oramic.jpg)

With a low battery life, low sun light and all, they can get a few things done before they have to call it a day.

Let us see what they can do. Hope they get something out of it.

Great stuff tho'.
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Re: International Military & Space Discussion

Post by NRao »

While it bounced it gathered info on the gravity on the comet.

It also competed a test of sending radio waves through the comet, that were received by Rosetta.

There are a few other tests/experiments that they have been to conduct.

The one that is going to be challenging is drilling into the surface and the harpoon also had an accelerometer to gauge the density of the comet at the landing site, which of course did not work.

They are thinking of what to do with the battery life coming to an end in another day or so. With a lack of sun light they do not expect the lander to last too long.
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Re: International Military & Space Discussion

Post by NRao »

http://www.esa.int/Our_Activities/Space ... ing_replay

More than an hours worth of talk.

Great info.

They know exact location of teh first landing site.

The first bounce took 1 hr 50 min and it landed about a Km away.

The second hop was smaller, perhaps a few meters.

The lander is on its side.
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Re: International Military & Space Discussion

Post by SaiK »

landing was super job.. though.. agreed! I was expecting it would have ricocheted into space. they keep saying like it is landing bullet on a bullet.. now, what is the actually speed of this 67P - 40 times faster than speeding bullet?
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Re: International Military & Space Discussion

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NASA tests 3D-printed rocket engine parts
PTI
COMMENT · PRINT · T T
TOPICS
science and technology
space programme
science and technology
NASA has successfully tested 3D manufactured copper parts for rocket engines and found they could withstand the heat and pressure required for space launches.

Aerojet Rocketdyne (AR) at NASA’s Glenn Research Centre in partnership with NASA successfully completed the first hot-fire tests on an advanced rocket engine thrust chamber assembly using copper alloy materials.

This was the first time a series of rigorous tests confirmed that 3D manufactured copper parts could withstand the heat and pressure required of combustion engines used in space launches, NASA said.

In all, NASA and AR conducted 19 hot-fire tests on four injector and thrust chamber assembly configurations, exploring various mixture ratios and injector operability points and were deemed fully successful against the planned test programme.

“The successful hot fire test of subscale engine components provides confidence in the additive manufacturing process and paves the way for full scale development,” said Tyler Hickman, lead engineer for the test at Glenn.

The work is a major milestone in the development and certification of different materials used in this manufacturing process, NASA said.

According to AR, copper alloys offer unique challenges to the additive manufacturing processes. The micro-structure and material properties can be well below typical copper.

So they have worked through a regimented process to optimise and lock down processing characteristics and have performed rigorous materials tests to know how the alloy performs structurally.

“Additively manufactured metal propulsion components are truly a paradigm shift for the aerospace industry,” said Paul Senick, Glenn project manager.

“NASA and its commercial partners continue to invest in additive manufacturing technologies, which will improve efficiency and bring down the cost of space launches and other earth applications,” said Senick.
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Re: International Military & Space Discussion

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Re: International Military & Space Discussion

Post by NRao »

landing was super job.. though.. agreed! I was expecting it would have ricocheted into space. they keep saying like it is landing bullet on a bullet.. now, what is the actually speed of this 67P - 40 times faster than speeding bullet?
The speed of 40 times faster ...... is relative to the rest, and not relative to the two.

The lander was at 1M/sec the first time it came in to land and 3 cm/sec on the final bounce. Both these numbers are relative to each other.

Also, on the first bounce it went up a whole Km and landed about a Km from the original site. That entire trip took 1hr 50mins.
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Re: International Military & Space Discussion

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Scientists say the Philae lander has begun drilling into its comet - although battery issues may stop them obtaining any data.

The team at the European Space Agency (ESA) hope to extract some of the material buried beneath the comet's surface.

But it is not clear whether it will succeed in taking samples, Stephan Ulamec, head of operations for Philae, said in an online briefing.

He added controllers still do not know exactly where the probe landed on comet 67P/Churyumov-Gerasimenko on Wednesday.

The Philae lander is the first spacecraft to touch down on a comet and has sent first images from the surface of the body.

But two harpoons that should have anchored it to the surface did not properly deploy when it landed.

That caused Philae to bounce and drift through the void for two hours before touching down again.

After a second, smaller bounce, scientists believe it came to rest in a shallow crater on the comet's 2.5-mile (4km)-wide body, or nucleus.

ESA mission control still has not been able to locate the probe, although it is believed to be next to a cliff that is blocking sunlight from its solar panels.

This means it has been operating on battery power, which is expected to run out in the next day or so.

"So the mechanism has worked, but unfortunately we have lost the link and we have no more data," he told reporters in the briefing.

Stephan Ulamec, head of operations for Philae, said right now it was unknown whether battery power would be sufficient to link back up with the probe.

"Maybe the battery will be empty before we get contact again," he said.

Meantime, he said the probe is receiving "very limited power" from its solar panels and project engineers are trying to determine how they might move them so they get more sunlight.

Even if Philae uses up all its energy, it will remain on the comet in hibernation mode for the coming months.

There is a chance it could wake up again if the body passes the sun in such a way that the solar panels catch more light.

Meanwhile, its mother ship, the Rosetta orbiter, will use all of its 11 instruments to gather as much data as possible .

Scientists hope the £1.03bn (1.3bn euro) project will help them better understand comets and other celestial objects, as well as possibly answer questions about the origins of life on Earth.
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Re: International Military & Space Discussion

Post by Victor »

The west has learned a lot from Rosetta. It will soon be possible to capture small city-size comets by attaching rocket engines to them and steering them to earth orbit or even moon orbit. Then they can become a source of mined raw material, a base for zero-gravity factories for hyper precision parts and a lot more. Good thing we have started our efforts on this by ourselves.
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Re: International Military & Space Discussion

Post by SSSalvi »

From the Tweets by Philae it appears that :
1. Exact location of Philae is not yet known
2. At least for now, ESA has abandoned firing Harpoons to fix the craft to comet surface
3. A few science experiments have been carried out
4. Solar illumination is not sufficient to charge the batteries sufficiently
5. Batteries are running out fast so ( and this is MY view .. not official position ) for the present they may not conduct comet measurements.

Battery discharge status for 14 hours: ( from ESA/Philae twitter )

Image

Detailed comments and explanations of scientific experiments: Last portion here.
Last edited by SSSalvi on 15 Nov 2014 09:52, edited 3 times in total.
NRao
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Re: International Military & Space Discussion

Post by NRao »

Batteries are running out fast so
Looks like it is worse than that. The power is so low that BBC is reporting that they go into a "standby mode". And obviously stop transmitting.

The worst case scenario is that they will not get any more info than they have got so far.

:(
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Re: International Military & Space Discussion

Post by krishnan »

they will , all it needs is few hrs of sunlight
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Re: International Military & Space Discussion

Post by SSSalvi »

Latest quotes from Rosetta Team Blog ( Blog title speaks a lot ):

Title of Blog : OUR LANDER’S ASLEEP

With batteries depleted and not enough sunlight ..., Philae has fallen into 'idle mode' ,.... all instruments .... are shut down.
Contact lost at 00:36 UTC.
No contact possible unless sufficient sunlight falls on the solar panels.

====

And its Twitter : I'm feeling a bit tired, did you get all my data? I might take a nap… zzzzzz

====

Update on earlier post : ( from other sources : )
1. SD2 drill experiment requires about 80 watt-hrs

2. On Whether 1.5 Hrs sunlight is sufficient to recharge for occasional useful bouts :

" .. very unlikely ..The battery has to be heated to 0 deg C for recharge. This requires 50W. Current solar power = 1.5 Hrs * 1W ( max ) + 20 min * 4W . "

---
So we have to wait for 1 AU from Sun ( Near perihelion ) when some chance of sporadic operations may be possible.

Solar radiation /sqM .. at 1 AU = 1286.31 ( near perihelion )
at 3 AU ( current distance ) = 142.92

Currently it is generating 1.5+1.6 = about 3 WH
so during perihelion it may generate 30WH=45W daily .. may be useful for one operation in 2 3 days .. just guess assuming that the generation is directly proportional to irradiance. ... expert opinion required.
Last edited by SSSalvi on 15 Nov 2014 23:46, edited 3 times in total.
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Re: International Military & Space Discussion

Post by Viv S »

When will they insert the nuclear warhead?!
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Re: International Military & Space Discussion

Post by Shreeman »

Ze comets name was Churyumov-Gerasimenko comet, until the falling out with russia. Now its only 67P.

Otherwise, a remarkable moment just passed.
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Re: International Military & Space Discussion

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http://www.theguardian.com/science/2014 ... s-darkness

Rosetta mission's Philae lander powers down in comet's darkness

Final attempt to jolt space lander into sunlight to recharge batteries fails – but officials still hope it could be revived in August 2015 when comet is closer to the sun

The audacious Rosetta mission’s attempt to land on a comet and send back scientific data is over – for now.

Despite a last-roll-of-the-dice attempt to nudge the Philae lander into better sunlight, which might have recharged its batteries, the end came when contact was lost at 00.36 GMT on Saturday morning.

Engineers had warned earlier in the day that the lander, which is the size of a washing machine, may not have had enough power to make contact at all.

There was still a tense wait at the European Space Agency’s (ESA)operations centre in Darmstadt, Germany, as Philae’s signal was not acquired until 02.19 GMT, more than an hour later than expected, raising hopes that the lander may have moved into a sunnier spot.

Data acquired during the night showed that Philae had moved a tiny bit, but not enough to immediately save the mission.

Scientists hope, however, that the comet Philae now calls home, known as 67P/Churyumov-Gerasimenko, will be close enough to the sun in August 2015 for the stronger sunlight to revive the lander.
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Re: International Military & Space Discussion

Post by Victor »

The comet is tumbling relative to the sun (12 hr ? ), so unless Philae is in a really deep hole, it should get glimpses of sunlight every few hours. How does getting closer to the sun improve chances? Don't understand.
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Re: International Military & Space Discussion

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deleted
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Re: International Military & Space Discussion

Post by SSSalvi »

^^^
Getting closer will improve the sunshine intensity .. not significantly the time .. ( modified earlier post with approx computation of likely increase in power generation budget ) .. it may generate 45W daily when at 1AU

If it was sitting in its 'pole' region then the illumination time would have changed but presently it is expected to be near 'equator' ( going by earth rotation convention ) so no significant variation.

====
Shreeman wrote:Ze comets name was Churyumov-Gerasimenko comet, until the falling out with russia. Now its only 67P.

Otherwise, a remarkable moment just passed.
Name of the comet is NOT 67P .. it is abbreviation of 67P/Churyumov-Gerasimenko

Addition of 67P is the naming convention adopted in 1994

Quoting from JPL data base : It was
" Discovered 1969-Oct-22 by Churyumov, Klim Ivanovic at Alma-Ata Observatory, Russia
discovered on plate/photo taken on 9/11 "
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Re: International Military & Space Discussion

Post by SaiK »

Viv S wrote:
When will they insert the nuclear warhead?!
You should ask Bruce Willis.
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http://www.spacedaily.com/reports/Comet ... s_999.html
Comet probe sends back drill experiment data in final hours
by Staff Writers
Paris (AFP) Nov 15, 2014


Europe's science probe Philae sent home a treasure trove of data from a comet heading towards the Sun before falling silent as its power ran out, mission control said Saturday.

Crowning a historic feat, the robot lab streamed data from its experiments back to its mother ship Rosetta in the final hours before its battery ran down.

This included the outcome of an eagerly-waited chemistry test of a sample drilled from the comet's icy and dusty surface, scientists said.

"Rosetta's lander has completed its primary science mission," the European Space Agency (ESA) said.

Lacking power, its instruments and most systems went into standby mode after three days of non-stop work, sending back data that will keep scientists busy for years.

"The data collected by Philae and Rosetta is set to make this mission a game-changer in cometary science," said Matt Taylor, Rosetta project scientist.

Philae had landed in a dark shadow after a bouncy triple touchdown Wednesday.

It did not get enough sunlight to recharge its batteries sufficiently to extend its mission beyond its initial 60-hour work programme.

Mission engineers do not rule out making contact with the lander in the coming months as Comet 67P/Churyumov-Gerasimenko moves closer to the Sun.

Conceived more than 20 years ago, the Rosetta mission aims at shedding light on the origins of the Solar System 4.6 billion years ago, and maybe even life on Earth.

A theory gaining ground in astrophysics is that the fledgling Earth was pounded by these bodies of cosmic ice and carbon-rich dust, seeding our planet with the basics to start life.

Rosetta and its payload travelled more than six billion kilometres (3.75 billion miles), racing around the inner Solar System before they caught up with the comet in August this year.

On Wednesday, Philae bade farewell to its mother ship and descended to a comet travelling at 18 kilometres (11 miles) per second, 510 million kilometres (320 million miles) from Earth.

The touchdown did not go entirely as planned -- hardly a surprise in an operation some gloomily predicted had only a one-in-two chance of success.

Philae landed smack in the middle of its targeted site, but a pair of anchoring harpoons failed to deploy.

It rebounded, touched down again, bounced up once more and then landed for the third time at a place believed to be about a kilometre (half a mile) from the landing site.

Philae found itself in the shadow of a cliff, tilted at an angle that left one of its three legs pointed to the sky.

Weighing 100 kilos (220 pounds) on Earth, Philae has a mass of just one gramme (0.03 of an ounce) -- less than a feather -- on the low-gravity, four-kilometre comet.

That meant just a jolt could have caused it to drift off into space.

And lack of sunlight for its solar panels meant it had to survive on a battery with a charge of around 60 hours, enough to carry out its scheduled scientific work.

- Race against time -

Stacked against the odds, the scientists resorted to every trick possible to use power miserly and keep Rosetta working without causing it to drift away.

Using the lander's toolkit of 10 instruments, they started with passive observation -- taking pictures, measuring the comet's density, temperature, and internal structure, "sniffing" molecules of gas from its surface -- that would not move the craft.

Finally, in the most important but riskiest experiment of all, they drilled a core of material out of the comet surface to analyse its chemical signature.

All the data had to be stored and dispatched back to Rosetta as the power indicators shrank towards the red zone.

"We received everything," mission scientist Jean-Pierre Bibring told AFP. "The word is 'fabulous,' just 'fabulous.'

The team's eagerly-awaited first report will be made at a meeting of the American Geophysical Union (AGU) in San Francisco next month.

The "67P" comet is due to loop around the Sun next year, flaring gas from its head and leaving a spectacular icy trail of ice from water stripped from its surface.

Rosetta will escort it until the comet heads back out towards the depths of the Solar System in December 2015.
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Re: International Military & Space Discussion

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Update on Philae 16Nov 0815 PST ( 1615GMT / 2145 IST )

Image of Philae captured by Rosetta after 1st bounce:

ESA has republished the Earlier image sequence .. with an addition of Philae in flight after 1st bounce,

The large circle is the dust that rose when Philae touched on the comet.

Image

After touchdown it could not harpoon the ground so it rebounced from surface and rose with about 40cms/sec. It is visible as a white dot ( identified as Philae in a small red circle ).

How do you confirm that it is not an artifact on surface? There is a tell tell shadow marked in the image.

Perhaps this is a starting point to identify a possible current resting place of orbiter because we now know the direction in which it travelled.
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Re: International Military & Space Discussion

Post by PratikDas »

NRao wrote:
PratikDas wrote: If components have been exposed to temperatures well beyond rated conditions, can one really afford to reuse the component just because it looks good?

Everything will have to be inspected and in many cases it may be more cost effective to simply replace.
I guess/think the rocket fell further away from the launch site. Very little stuff must have fallen on the site itself.
Now we have an assessment:

State assessing damage, considering future of commercial spaceport
Nov 13, 2014
The incident last month could have been worse, but Layne said it will cost between $13 million and $20 million to repair the damage.

The state has already invested more than $100 million in the facility.
NRao
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Re: International Military & Space Discussion

Post by NRao »

Image
Philae descending towards and across the comet (European Space Agency)
SaiK
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Re: International Military & Space Discussion

Post by SaiK »

http://www.universetoday.com/116423/phi ... t-of-dust/

instrument hammered a probe as hard as they could into 67P’s skin but only dug in a few millimeters
“Although the power of the hammer was gradually increased, we were not able to go deep into the surface,”

“If we compare the data with laboratory measurements, we think that the probe encountered a hard surface with strength comparable to that of solid ice
it does not make sense to me.
krishnan
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Re: International Military & Space Discussion

Post by krishnan »

hmmm , frozen water , is that what comets are made of ?
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