Harish Palaniappan's

Parcel delivery from space, experiment attempted:

Imagine you are kid in a high-rise residential apartment, say on the 13th floor.. and you wanted to deliver a box parcel to your friend in the 4th floor. As a kid you would probably tie the box to a long rope and slowly drop it near the 4th floor where your friend picks it up.. (and ofcourse you make sure you get back the rope)

This same thing was tried recently by a russian space mission where they wanted to test a parcel delivery from a spacecraft 500km away from earth.. What was planned is like this: They had a spherical capsule for the parcel.. tied to a tether (fiber rope) which they planned to drop towards earth.. since at space the parcel is assumed zero weight the rope only had to be a holder rather than a carrier for the weight. .. once within a space where there's considerable gravitational pull from the earth, they wanted to release the rope from the spacecraft, so that the capsule entered earth by the gravitational pull and once inside earth's atmosphere it would parachute to ground or water.

Some 500 students all over the world were preparing the experiment which went on board a russian unmanned space vehicle. The vehicle which itself was an experiment.. being an unmanned vehicle, was carrying a few other experiments like this parcel thing.

Since the spacecraft was 500km away, the rope had to be atleast some percentage of that to stretch the parcel towards earth's gravity.. so the rope was 30km long (probably wound into a coil placed inside the spacecraft).

Also, once the rope is uncoiled to its full length stretching the parcel down, there was a plan to swing the vehicle in such a way that while releasing the rope the parcel at the end of it, due to the swing, would have some momentum to move faster towards the earth(otherwise it had the risk of losing track to any other planet's gravitational pull).

Unfortunately.. while performing this test, the rope probably failed unwinding or uncoiling after about 8.2 kms of unwinding... probably got stuck.. they had to cut down the rope without having 30km of it deployed and so the experiment was a failure.

But the attempt was interesting to learn about. This test was to find out whether this could be a low cost method of transfering heavy cargo or equipment back to earth from future space missions, rather than spending all that fuel and cost to have a space vehicle like 'space shuttle' carry cargo back to earth.

I was amazed at the idea.. Imagine, a whopping 30km long rope hanging from a space vehicle trying to release a parcel back to earth.

Other things I was amazed about:
> That the rope or tether used was half-a-millimeter thick.. just (.5mm).. obviously, otherwise how would have they got 30km of it coiled in a vehicle.
> They made the rope with a material called Dyneema which they say is the world's most strongest fibre.. also used by kite surfers.

What I probably wondered or didn't like was:
> Why did they require more than 500 students to design or plan this.. 500 is a very large number. I doubt whether all 500 students participated actively in the project, or whether they all just subscribed to it like subscribing to some yahoo group.
> Also, it would have taken a hell a lot of time with so much people, to agree upon all the design components for this experiment.

Links:
PDF document on the experiment

Analysts have been even thinking of tethered satellite stuff.. satellites connected to another by tether.. read about this here.

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NASA's two kids in mars have a happy life:

It has been three years and NASA's mars rover machines, the SPIRIT and the OPPORTUNITY are still listening to commands from earth and are actively researching the martian soil further, sending photographs,etc.,

The machines originally designed only with a plan to make sure they sustain atleast 90 days on Mars, now living up to 3 years, and recently surviving a 6-week long huge dust storm without being disconnected from communications with earth, is all great news for the team behind it.

It seems the controllers on earth stations for the two machines, did a great job during the dust storm, in ensuring that whatever possible was switched off on the machines(except communications with earth of course) to make them use less power because during the dust storm the machines don't receive enough sunlight to generate electricity through their solar panels.

Last month, NASA has sent another machine to mars.. the PHOENIX.. (launched August 2007 from earth), and the travel would take so long that PHOENIX would reach mars only in May 2008.

Imagine! if mars had water and they decided to send a few people up there.. it would be a 9 month travel.. in all the darkness of space, with all unfriendly things around.. and further, in zero gravity.

he he.. I have a list of friends who I want to nominate for such a travel.. :o)

Links:
Mars exploration details

Image sources:
NASA.gov, esa.int, spacetoday.org