Chandrayan-1 moon mission

SwamyG
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Re: Chandrayan-1 mission launched succesfully

Postby SwamyG » 01 Nov 2008 00:29

A question to gurus. Say in all the subsequent firings, if the yaan flies past the moon, it is not that it just is going to permanently overshoot, right? It is still going to orbit earth with a higher apogee. In that case, reverse firing would be conducted to bring it back into moon's clutches. This will just spend more fuel and reduce the lifetime. Am I correct, or am I totally clueless about the theory and practice?

thanks.

Abhijit N
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Re: Chandrayan-1 mission launched succesfully

Postby Abhijit N » 01 Nov 2008 03:49

http://www.isro.org/pressrelease/Oct31_2008.htm

FIRST PICS

http://www.isro.org/pslv-c11/photos/chandrayaan/image1.jpg

http://www.isro.org/pslv-c11/photos/chandrayaan/image2.jpg

The Terrain Mapping camera (TMC) on board Chandrayaan-1 spacecraft was successfully operated on October 29, 2008 through a series of commands issued from the Spacecraft Control Centre of ISRO Telemetry, Tracking and Command Network (ISTRAC) at Bangalore.Earth as Viewed by Chandrayaan-1: Click for Full Image Analysis of the first imagery received by the Indian Deep Space Network (IDSN) at Byalalu and later processed by Indian Space Science Data Centre (ISSDC) confirms excellent performance of the camera.The first imagery (image 1) taken at 8:00 am IST from a height of 9,000 km shows the Northern coast of Australia while the other (image 2) taken at 12:30 pm from a height of 70,000 km shows Australia’s Southern Coast.


TMC is one of the eleven scientific instruments (payloads) of Chandrayaan-1. The camera can take black and white pictures :cry: of an object by recording the visible light reflected from it. The instrument has a resolution of about 5 metres.

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Re: Chandrayan-1 mission launched succesfully

Postby shiv » 01 Nov 2008 06:13

SwamyG wrote:A question to gurus. Say in all the subsequent firings, if the yaan flies past the moon, it is not that it just is going to permanently overshoot, right? It is still going to orbit earth with a higher apogee. In that case, reverse firing would be conducted to bring it back into moon's clutches. This will just spend more fuel and reduce the lifetime. Am I correct, or am I totally clueless about the theory and practice?

thanks.


Reply from a moderately clueless person.

i don't think it is meant to overshoot the moon while being in earth orbit. I think the earth orbits are merely to use earth's gravity to accelerate the spacecraft (with a little help from the engines) to achieve a velocity that will enable the craft to escape the earth's gravity. This must be timed well enough for the craft be captured by the moon's gravity rather than allowing the spacecraft to go on a wild trip into space.

But I have a question to gurus as well

The Chandrayaan is supposed to orbit 100 km above the moon. Exactly what would be the reasons for gradual orbital decay requiring the use of fuel (that should last up to two years)?. Would it be variations in the moons gravity? Would it be perturbations in orbit caused by the earths or sun's gravity? Djinns?

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Re: Chandrayan-1 mission launched succesfully

Postby UPrabhu » 01 Nov 2008 06:57

shiv wrote:
The Chandrayaan is supposed to orbit 100 km above the moon. Exactly what would be the reasons for gradual orbital decay requiring the use of fuel (that should last up to two years)?. Would it be variations in the moons gravity? Would it be perturbations in orbit caused by the earths or sun's gravity? Djinns?


I am no Guru but I think... http://en.wikipedia.org/wiki/Mascon + Earth + Sun gravitational influence... Whats the impact of Solar Wind?

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Re: Chandrayan-1 mission launched succesfully

Postby SriKumar » 01 Nov 2008 07:31

shiv wrote: The Chandrayaan is supposed to orbit 100 km above the moon. Exactly what would be the reasons for gradual orbital decay requiring the use of fuel (that should last up to two years)?. Would it be variations in the moons gravity? Would it be perturbations in orbit caused by the earths or sun's gravity? Djinns?
I am no guru either but my (pure) guess would be that fuel would be needed to keep the satellite oriented/pointed in the correct direction as it orbits the moon- since the same side should face the moon all the time. Also, any motion within the satellite (e.g. a camera being rotated) would cause attitude change, which also have to be corrected for, needing fuel. IMHO, these are reasons why (earth) orbiting satellites need fuel. There might be other 'lunar reasons' that I surely have missed.

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Re: Chandrayan-1 mission launched succesfully

Postby UPrabhu » 01 Nov 2008 07:44

SriKumar wrote:I am no guru either but my (pure) guess would be that fuel would be needed to keep the satellite oriented/pointed in the correct direction as it orbits the moon- since the same side should face the moon all the time. Also, any motion within the satellite (e.g. a camera being rotated) would cause attitude change, which also have to be corrected for, needing fuel. IMHO, these are reasons why (earth) orbiting satellites need fuel. There might be other 'lunar reasons' that I surely have missed.


I thought reaction wheels are used for orientation. Fuel is to keep the orbit stable.

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Re: Chandrayan-1 mission launched succesfully

Postby disha » 01 Nov 2008 08:22

shiv wrote:Reply from a moderately clueless person.

i don't think it is meant to overshoot the moon while being in earth orbit. I think the earth orbits are merely to use earth's gravity to accelerate the spacecraft (with a little help from the engines) to achieve a velocity that will enable the craft to escape the earth's gravity. This must be timed well enough for the craft be captured by the moon's gravity rather than allowing the spacecraft to go on a wild trip into space.


Correct. Also by aiming the craft at the centre of the moon, moon's gravity is also utilized to tug Chandrayaan towards it. Of course, if not timed well, it will crash on moon itself.

But I have a question to gurus as well

The Chandrayaan is supposed to orbit 100 km above the moon. Exactly what would be the reasons for gradual orbital decay requiring the use of fuel (that should last up to two years)?. Would it be variations in the moons gravity? Would it be perturbations in orbit caused by the earths or sun's gravity? Djinns?


Moon like Earth is not a perfect sphere. Neither its density is uniform. Just like on Earth, there are gravity anomalies on Moon. This causes perturbations in the orbit. In orbit, if the satellite encounters a gravity well [higher density of material say Iridium] the satellite deviates down from the orbit. Likewise the satellite deviates up from the orbit when it encounters lesser gravity [region with lower density, say material blasted out of a large crater]. This perturbations add up fast and interfere with measurements [in case of Chandrayaan]. Also note that Chandrayaan is on a polar orbit, so the deviations are not just up and down but left and right [from the satellite's perspective] - on top of it add up pressure from the solar wind and other bodies and of course djinns and the need for house keeping.

Also note that attitude changes and re-orientation for different measurements require fuel, but that accounts for a very small percentage.

If more fuel is conserved, the satellite can be operated for a longer duration. Some of India's IRS satellites even though slated nominally for 2-4 years of operation lasted more than a decade [the same cannot be said for Panda's in orbit]. For Chandrayaan-1, once it gets moon completely map'ed it will provide such a comprehensive date for the next missions that it will contain optimal fuel for the given mission.

[Added later: The deviations are not just up and down and left and right, but in different angles as well, I would love to say in all eight cardinal directions :lol: ]

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Re: Chandrayan-1 mission launched succesfully

Postby disha » 01 Nov 2008 08:44

Abhijit N wrote:
TMC is one of the eleven scientific instruments (payloads) of Chandrayaan-1. The camera can take black and white pictures :cry: of an object by recording the visible light reflected from it. The instrument has a resolution of about 5 metres.


The resolution of image is more important than the visible color of the image. Chandrayaan-I has a 5m resolution, that is it can identify objects as small as a size of the bus. For the first moon shot, this is incredible.

Also, visible spectrum is a very tiny spectrum of the Electro-magnetic spectrum! In the case of moon, it is the HySI [Hyper Spectral Imager] and HEX [Hi-Energy X-Ray Spectrometer] that will be interesting. In fact, comparing the payloads on C-I is a futile exercise, it is a well thought out plan and will give us more information than most of the moon missions in the past put together.

Put it this way, we as humans have gone to moon, but we do not know the mineral distribution of moon!!

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Re: Chandrayan-1 mission launched succesfully

Postby Prasenjit Medhi » 01 Nov 2008 08:45

shiv wrote:
SwamyG wrote:A question to gurus. Say in all the subsequent firings, if the yaan flies past the moon, it is not that it just is going to permanently overshoot, right? It is still going to orbit earth with a higher apogee. In that case, reverse firing would be conducted to bring it back into moon's clutches. This will just spend more fuel and reduce the lifetime. Am I correct, or am I totally clueless about the theory and practice?

thanks.


Reply from a moderately clueless person.

i don't think it is meant to overshoot the moon while being in earth orbit. I think the earth orbits are merely to use earth's gravity to accelerate the spacecraft (with a little help from the engines) to achieve a velocity that will enable the craft to escape the earth's gravity. This must be timed well enough for the craft be captured by the moon's gravity rather than allowing the spacecraft to go on a wild trip into space.

But I have a question to gurus as well

The Chandrayaan is supposed to orbit 100 km above the moon. Exactly what would be the reasons for gradual orbital decay requiring the use of fuel (that should last up to two years)?. Would it be variations in the moons gravity? Would it be perturbations in orbit caused by the earths or sun's gravity? Djinns?


Hardly a guru, but orbit decline over Earth/Moon is primarily caused by gravity, which slowly overcomes even the high velocity of several thousand kmph, and angular acceleration of the spacecraft. The tangential accelerational pull of the larger central object eventually causes the satellite to come crashing down. In Earth, nascent atmosphere in Near Space, LEO, also causes marginal atmospheric drag. In the case of a lunar satellite, I would assume that the Earth's gravity would play a significant role as well, an Earth tide effect on the moon. Solar wind of (extremely) high velocity charged particles is also a minor factor, out in deep space, but the primary factor is of course lunar gravity. Correct me if I'm wrong.

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Re: Chandrayan-1 mission launched succesfully

Postby juvva » 01 Nov 2008 09:29

SwamyG wrote:How Chandrayaan-1 is raised to higher orbits
Chandrayaan-1 could have been fired to reach the moon, which is about 3,84,000 km from earth, in one shot. But that was not done. Instead the spacecraft is being moved towards the moon in increasingly elliptical orbits with an apogee (farthest point from the earth) increasing many times more than the perigee.

“We could have done it one shot, but there is a possibility of missing the moon,” said M. Annadurai, Project Director of Chandrayaan-1 to this Correspondent. “So we have adopted an incremental increase in the orbits’ perigee.”

That probably explains why the Indian Space Research Organisation (ISRO) has decided to settle for five increasingly elliptical orbits before Chandrayaan-1 reaches the moon’s sphere of influence. Why is the firing always undertaken at the perigee position?

Firing at perigee
“To increase the apogee, we must fire at the perigee [position]. And firing should consume less energy. So the firing is done at the perigee,” Dr. Annadurai explained.

One more reason to fire at the perigee is to ensure that the spacecraft can be tracked by 3-4 ground stations. “The spacecraft is allowed to complete one or more orbits till such time 3-4 ground stations can track it. But we will fire it at the earliest opportunity,” he said.

But not always can one assume that the firing will happen as planned. So any change in this will in turn affect the apsidal line (imaginary line that connects the apogee and perigee). This should be corrected and maintained if the rendezvous with the moon is to happen.

Increasing the apogee
And what ensures that the apogee increases many hundred kilometres after every firing while the perigee changes by only a few kilometres? “When the firing is done exactly at perigee, the velocity increases and the apogee keeps increasing. There will be no change in the perigee position,” he said.

But firing the spacecraft exactly at the perigee position is only theoretically possible. This results in a small change in the perigee altitude.

Duration of firing
“It is not an instant firing [at the perigee]. It takes a few hundred seconds to complete the firing,” he said. But great effort is however taken to centre the firing around the perigee position.

For instance, the first firing to take Chandrayaan-1 from the initial orbit to the first orbit (with an apogee of 38,000 km) took about 1060 seconds to complete. The second firing to take the spacecraft to the nearly 75,000 km apogee took 920 seconds. And the third firing to raise it to about 1,65,000 km apogee took 560 seconds.

The fourth firing to take Chandrayaan-1 to 2,67,000 km will take about 190 seconds and finally the last raise to 3,80,000 will take 150 seconds.

Though the original plan was to reach 2,00,000 km apogee in the third orbit, ISRO could only raise it to 1,65,000 km. So will that lead to any problems? “This can be made up for in the next firing,” Dr. Annadurai said.

Image
Use of propellant
Will the change in the orbit-transfer strategy from five-and-half days to nearly a fortnight lead to increased fuel consumption and hence reduced mission life? “The amount of propellant required to fire the spacecraft to 4,00,000 km is less, whether it is done in one shot or in stages. And the propellant is used only for changing the orbits and not for orbiting around the earth,” he explained.

Orbiting around the earth is mainly through the gravitational force of the earth. But the gravitational influence of sun and moon would still play a role, though minor. Since the spacecraft goes around only for a few days in each orbit, there will not be any change in the orbits and hence the need to use propellant to correct the orbits would not arise.

But that will not be case when Chandrayaan-1 orbits the moon for two years. “There will be a need to correct the orbit once in two weeks to maintain a 100 km circular orbit,” said Dr. Annadurai.

Less energy required
While earth’s gravitational force will exist even when the spacecraft moves further and further away from the earth, the force will decrease with distance. “So firing it to the fourth and fifth orbit will require less energy,” said Dr. Annadurai. “Since some propellant is already used in the previous firings, the overall mass would come down. So the effort required to fire reduces.”

Reverse firing
Five-and-half days after the fifth firing, Chandrayaan-1 will have its rendezvous with the moon. Chandrayaan-1 will get nearer to the moon on November 8 when it reaches the 3,81,000 km apogee.

Though the moon’s influence will be predominant, the velocity of Chandrayaan-1 has to be reduced to enable the moon to capture it. Else, it can fly past the moon.

Once captured by the moon’s gravity, the velocity of the spacecraft has to be reduced to help it reach its final destination of 100 km circular orbit around the moon.

This is achieved by reversing what was done to raise its orbits.

“First, the firing is resorted at both perigee and apogee positions. And the firing takes place only after the orientation of the spacecraft is reversed — turned 180 degrees,” he said.

While the momentum of the spacecraft allows it to move in the same direction, the reverse firing helps it to reduce the velocity. The reduction in velocity is again undertaken in an incremental manner to reach the predetermined 100 km circular orbit around the moon.


All this is getting tense and exciting, A few questions:

Looks like the LAM will be fired for a total of ~10 times. This may be the highest number of times that this engine is fired in space? What is the rating of this engine for number of on/off operations?

For lunar orbital corrections will the LAM be fired again or will it be done by the smaller attitude control motors?
( edited later: I mean corrections after it reaches the final 100km orbit)

Is the fuel for LAM and attitude control motors same and shared from the same fuel tank?

Thanks!

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Re: Chandrayan-1 mission launched succesfully

Postby SSridhar » 01 Nov 2008 10:36

SwamyG wrote:Say in all the subsequent firings, if the yaan flies past the moon, it is not that it just is going to permanently overshoot, right? It is still going to orbit earth with a higher apogee. In that case, reverse firing would be conducted to bring it back into moon's clutches. This will just spend more fuel and reduce the lifetime.


SwamyG, let me attempt.

There is a point between the Earth and the Moon, approximately 0.9 times the Earth-Moon distance where the gravitational pull on the spacecraft (Chandrayaan-I) from the moon and the Earth would be equal and opposite in direction and cancel out. This neutral point, L1, is called the Libration Point (referred to in an earlier post in this thread). Without other influences if a spacecraft were to be placed at this point with zero velocity, it should simply continue to stay at that position forever. Once the spacecraft crosses L1 and comes firmly within the the Moon's sphere of influence (which in fact extends about 66200 Km from the moon's centre), we can calculate the spacecraft's orbit using selenocentric Keplerian trajectories.

There is a remarkable fact discovered by the Russians that any spacecraft sent from Earth will always enter the moon's sphere of influence that will be in excess of its selenocentric escape velocity at the boundary of the moon's sphere of influence. At the boundary, the escape velocity is 0.383 km/sec. The spacecraft will have apprx. 10.9 Km/sec velocity at this point in time, say T1. The spacecraft will therefore follow a hyperbolic trajectory around the moon. Of course, by the time, the spacecraft in its hyperbolic trajactory around the moon leaves the moon's sphere of influence, say at time T2, moon would have moved to a newer location in orbit. So, it is between these two times T1 & T2, that the lunar orbit will be shaped by turning around the spacecraft and retro firing the LAM.

The overshoot occurs only when the spacecraft and moon do not arrive properly.

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Re: Chandrayan-1 mission launched succesfully

Postby sumishi » 01 Nov 2008 13:27

From "Apollo in Perspective - Spaceflight Then and Now" by Jonathan Allday:
About four hours and two orbits later the service module engine was fired again to circularize the orbit ... at 100 km by 120 km. Interestingly this was a very well designed orbit as the variations in the Moon's gravity (due to mascons etc) would make it totally circular by the time the LM was due to dock with the command module again after the landing.


Seems the 100km Lunar orbit, which ISRO too is going to use, works well with regards to stability for spacecrafts orbiting the Moon.

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Re: Chandrayan-1 mission launched succesfully

Postby SSridhar » 01 Nov 2008 15:37

In my post above, I made a wrong statement about the speed of the spacecraft as it comes near the moon. It cannot be 10.9 Km/sec.

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Re: Chandrayan-1 mission launched succesfully

Postby Prasenjit Medhi » 01 Nov 2008 16:02

disha wrote:
shiv wrote:Reply from a moderately clueless person.

i don't think it is meant to overshoot the moon while being in earth orbit. I think the earth orbits are merely to use earth's gravity to accelerate the spacecraft (with a little help from the engines) to achieve a velocity that will enable the craft to escape the earth's gravity. This must be timed well enough for the craft be captured by the moon's gravity rather than allowing the spacecraft to go on a wild trip into space.


Correct. Also by aiming the craft at the centre of the moon, moon's gravity is also utilized to tug Chandrayaan towards it. Of course, if not timed well, it will crash on moon itself.

But I have a question to gurus as well

The Chandrayaan is supposed to orbit 100 km above the moon. Exactly what would be the reasons for gradual orbital decay requiring the use of fuel (that should last up to two years)?. Would it be variations in the moons gravity? Would it be perturbations in orbit caused by the earths or sun's gravity? Djinns?


Moon like Earth is not a perfect sphere. Neither its density is uniform. Just like on Earth, there are gravity anomalies on Moon. This causes perturbations in the orbit. In orbit, if the satellite encounters a gravity well [higher density of material say Iridium] the satellite deviates down from the orbit. Likewise the satellite deviates up from the orbit when it encounters lesser gravity [region with lower density, say material blasted out of a large crater]. This perturbations add up fast and interfere with measurements [in case of Chandrayaan]. Also note that Chandrayaan is on a polar orbit, so the deviations are not just up and down but left and right [from the satellite's perspective] - on top of it add up pressure from the solar wind and other bodies and of course djinns and the need for house keeping.

Also note that attitude changes and re-orientation for different measurements require fuel, but that accounts for a very small percentage.

If more fuel is conserved, the satellite can be operated for a longer duration. Some of India's IRS satellites even though slated nominally for 2-4 years of operation lasted more than a decade [the same cannot be said for Panda's in orbit]. For Chandrayaan-1, once it gets moon completely map'ed it will provide such a comprehensive date for the next missions that it will contain optimal fuel for the given mission.

[Added later: The deviations are not just up and down and left and right, but in different angles as well, I would love to say in all eight cardinal directions :lol: ]


And I thought it was just a case of the satellite not having escape velocity :) ? Would the effect of orbit perturbations due to marginal differences in the overall lunar gravitational pull exceed perturbations caused by the simple vibrations caused by the operation of rocket motors on board the spacecraft and could be safely discounted vis-a-vis the effect of earth gravity causing tidal force on the craft itself, solar wind, and of course the lunar gravitational elephant that you're not mentioning :) ?

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Re: Chandrayan-1 mission launched succesfully

Postby SwamyG » 01 Nov 2008 18:51

Thanks to all guru log.
Sridhar: My question is when both moon and the yaan enter the right space at the right time, but the yaan's velocity is simply greater (as per your note, > 10.9Km/s) - like the ball leaving the cricket bat, flying through, say the slip fielder's influence, but just traveling too fast. In the cricket case, the ball simply goes to the boundary. In the case of our yaan, say it was traveling at speeds > 10.9km/s; then the moon does not capture it. Since it crossed L1, is the yaan then lost? Or would be be able to fire it to bring it back?

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Re: Chandrayan-1 mission launched succesfully

Postby SSridhar » 01 Nov 2008 19:08

SwamyG, as I corrected subsequently, the velocity was incorrect. As it reaches the apogee the velocity falls. However, moon will fail to capture only when the spacecraft does not enter the moon's sphere of influence which is a sphere of 66200 Km surrounding the moon. The velocity of the spacecraft doesn't matter (actually, the relative velocity of the spacecraft wrt to that of the moon). It will still be captured by the moon.

Unlike the slip fielder, who does not have a gravitational force and which therefore requires him to firmly clasp the ball, the moon has one which will then determine the shape of the spacecraft's trajectory. The spacecraft can still escape the moon's sphere of influence after being captured or even crash on it depending upon the speed. But, it will be certainly captured if the spacecraft and the moon arrive at the right place and time, irrespective of the velocity of the craft.

IIRC, the earliest Russian lunar craft simply escaped the moon.

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Re: Chandrayan-1 mission launched succesfully

Postby vishwakarmaa » 01 Nov 2008 19:26

disha wrote:Put it this way, we as humans have gone to moon, but we do not know the mineral distribution of moon!!


Interesting that Armstrong went to the Moon, jumped on it three times in hollywood style and came back without any valuable information. After that day, Americans never looked back at Moon. World wonders, why?

Now, as Asians initiated moves to explore moon, they decided to restart their Moon campaign. Seems they suddenly realized something now, which they missed 4 decades back. Maybe Armstrong forgot something back?

Funny. World is round. :lol:

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Re: Chandrayan-1 mission launched succesfully

Postby sunilUpa » 01 Nov 2008 19:36

vishwakarmaa wrote:
disha wrote:Put it this way, we as humans have gone to moon, but we do not know the mineral distribution of moon!!


Interesting that Armstrong went to the Moon, jumped on it three times in hollywood style and came back without any valuable information. After that day, Americans never looked back at Moon. World wonders, why?


Funny. World is round. :lol:


:shock: :shock: :shock: Wonder where else all those Apollo missions (Apollo 12 to 17) landed, if not on moon!

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Re: Chandrayan-1 mission launched succesfully

Postby svinayak » 01 Nov 2008 21:53

sunilUpa wrote:

:shock: :shock: :shock: Wonder where else all those Apollo missions (Apollo 12 to 17) landed, if not on moon!

Area 51 - California

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Re: Chandrayan-1 mission launched succesfully

Postby Daedalus » 01 Nov 2008 22:29

Acharya wrote:
sunilUpa wrote:

:shock: :shock: :shock: Wonder where else all those Apollo missions (Apollo 12 to 17) landed, if not on moon!

Area 51 - California


Area 51 is in Nevada a state next to California, also it is to the north of Las Vegas.

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Re: Chandrayan-1 mission launched succesfully

Postby svinayak » 01 Nov 2008 22:40

Stand corrected

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Re: Chandrayan-1 mission launched succesfully

Postby Gerard » 01 Nov 2008 22:42

Daedalus wrote:Area 51 is in Nevada a state next to California, also it is to the north of Las Vegas.


The Nevada fake location is all part of the conspiracy....
:rotfl:

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Re: Chandrayan-1 mission launched succesfully

Postby Jagan » 01 Nov 2008 23:01

Gerard

Can you check our PM inbox and respond?

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Re: Chandrayan-1 mission launched succesfully

Postby kit » 01 Nov 2008 23:03

or better yet.,the americans know something about the moon that the rest of world doesnt know :) ISRO s heart is in the right place when they said they want to explore Mars maybe land an antrikshyatri on Mars .. they do have a vision ..that is something the very best have .. instead of being second rate

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Re: Chandrayan-1 mission launched succesfully

Postby sumishi » 01 Nov 2008 23:14

disha wrote:Put it this way, we as humans have gone to moon, but we do not know the mineral distribution of moon!!


Here is an interesting link - [The Colors of the Moon] from Russell Croman Astrophotography, which says:
Is the moon really this colorful? In a way, yes. The lunar surface actually does have quite a bit of color, although in reality it is very subtle. In this photograph, the color saturation has been enhanced to bring out the differences in the colors of the various areas of the surface. The hues are correct, just much more vivid than we usually see them.

Aside from making an interesting aesthetic presentation, the colors also give clues as to the mineralogy of the moon's surface. Also, at the sites of many impact craters we can see that deeper material exposed (and in some cases scattered) by the impact is of a different composition than the material on the surface.


This was also published in space.com as the 'image of the day' [Link], and in the American Scientist magazine, May-June 2008 issue.

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Re: Chandrayan-1 mission launched succesfully

Postby Gerard » 02 Nov 2008 00:18

Jagan wrote:Can you check our PM inbox and respond?


email sent

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Re: Chandrayan-1 mission launched succesfully

Postby Lalmohan » 02 Nov 2008 00:24

Gerard wrote:
Daedalus wrote:Area 51 is in Nevada a state next to California, also it is to the north of Las Vegas.


The Nevada fake location is all part of the conspiracy....
:rotfl:


you don't mean the 'special hangers' at China Lake do you?

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Re: Chandrayan-1 mission launched succesfully

Postby p_saggu » 02 Nov 2008 00:42

Can some guru clarify this.
The chandrayaan's camera that took those BW pics of the earth has a 5m resolution. Is resolution dependent on the height of the spacecraft from the surface? What I mean is that if CY is say at a 200 km altitude, it could identify a 5m object clearly, maybe if it got closer it could have a better resolution?

I hope the Chandrayaan takes pictures of NASA's Apollo moon landings and puts the conspiracy theories to rest once and for all. Is it possible with these camera resolutions?

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Re: Chandrayan-1 mission launched succesfully

Postby Lalmohan » 02 Nov 2008 00:50

how do you know for sure that Chandrayaan is in space and not in phillum-city in amchi mumbai?

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Re: Chandrayan-1 mission launched succesfully

Postby vishwakarmaa » 02 Nov 2008 01:04

p_saggu wrote:I hope the Chandrayaan takes pictures of NASA's Apollo moon landings and puts the conspiracy theories to rest once and for all. Is it possible with these camera resolutions?


ISRO has better things to do, than looking for someone's lost underwear's on moon.

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Re: Chandrayan-1 mission launched succesfully

Postby AdityaM » 02 Nov 2008 01:07

Lalmohan wrote:how do you know for sure that Chandrayaan is in space and not in phillum-city in amchi mumbai?


Do u see any item songs involving the CY1?
Last edited by AdityaM on 02 Nov 2008 01:52, edited 1 time in total.

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Re: Chandrayan-1 mission launched succesfully

Postby vishwakarmaa » 02 Nov 2008 01:09

^^^

Moonmoon sen?

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Re: Chandrayan-1 mission launched succesfully

Postby Rahul M » 02 Nov 2008 01:11

:rotfl: :rotfl: :rotfl:

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Re: Chandrayan-1 mission launched succesfully

Postby disha » 02 Nov 2008 01:20

sumishi wrote:
disha wrote:Put it this way, we as humans have gone to moon, but we do not know the mineral distribution of moon!!


Here is an interesting link - [The Colors of the Moon] from Russell Croman Astrophotography, which says:
... In this photograph, the color saturation has been enhanced to bring out the differences in the colors of the various areas of the surface. The hues are correct, just much more vivid than we usually see them.

Aside from making an interesting aesthetic presentation, the colors also give clues as to the mineralogy of the moon's surface. Also, at the sites of many impact craters we can see that deeper material exposed (and in some cases scattered) by the impact is of a different composition than the material on the surface.


This was also published in space.com as the 'image of the day' [Link], and in the American Scientist magazine, May-June 2008 issue.


I can also photoshop the image of moon and boost the saturation to give "clues" ... will it be scientifically acceptable? Will it be useful? It is basically a pretty picture [and confirmation of] what we already know! Not what we want to know. Will it give for example the Iron mineral distribution on moon? No those rust colored parts is not Iron Oxide! So what is the blue colored region? Of course it is a deeper material and shows up gray on a high res B&W. Is it original lava? What is it? What is its mineral content? What is the mineral distribution of that content? How deep does it go? How was it formed? How is it being transformed? What are the processes in place to transform them?

Fact is, if even a clueless noob like me can ask those questions, it means that the larger scientific community is salivating to ask more and seek even more answers! A pretty picture will not cut it, even if it is printed in Scientific American!

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Re: Chandrayan-1 mission launched succesfully

Postby SwamyG » 02 Nov 2008 03:13

Sridhar saar nomba nanri :-) (Sridhar sir, lots of thanks)

My question was badly phrased, but your explanation has been great. Apart from being an expert on Pakistan mamas you seem to be an expert of Ambuli mama as well.

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Re: Chandrayan-1 mission launched succesfully

Postby harbans » 02 Nov 2008 03:15

I hope the Chandrayaan takes pictures of NASA's Apollo moon landings and puts the conspiracy theories to rest once and for all.

If there's nothing there, than the 100 million USD payload that NASA has piggybacked on Chandrayaan has possibly a tinker bit of C4 to finish Chandrayaan at an appropriate time.

I'm actually a bit surprised that NASA invested 100m USD on one of it's 2 payloads. Thats an awful lot of faith to put in a mission that costs just 85m USd for India. Major Earth remote sensing satellites for launch India charges 10-11 million USD..(Italian one last year for example). I agree satellites do cost, but putting 100 m USD on a 1st Indian lunar mission is very optimistic for NASA..this will be the SINGLE biggest investment anyone has ever externally made in India's space programme.

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Re: Chandrayan-1 mission launched succesfully

Postby SwamyG » 02 Nov 2008 03:25

Guru log, a humble request. A few posts here and there about China, America, Japan ithyadi nations and conspiracy theories are fine and dandy. Let us keep such posts within tolerable limits.

choti mooh badi bath karke maaf kar dena......

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Re: Chandrayan-1 mission launched succesfully

Postby hnair » 02 Nov 2008 05:40

Gerard wrote:
Daedalus wrote:Area 51 is in Nevada a state next to California, also it is to the north of Las Vegas.


The Nevada fake location is all part of the conspiracy....
:rotfl:


conspiracy goes even deeper than that - the real location of that fake location is in the moon, NASA carefully made it to look like Nevada, so they can attract gamblers in the future. If you look at NASA's funding, most of them come from Moonlight Bunny Ranch, Ceaser's Palace and Joe's By The Bucket Clam Shack.

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Re: Chandrayan-1 mission launched succesfully

Postby vishwakarmaa » 02 Nov 2008 06:36

harbans wrote:If there's nothing there, than the 100 million USD payload that NASA has piggybacked on Chandrayaan has possibly a tinker bit of C4 to finish Chandrayaan at an appropriate time.


And who knows, maybe Cyaan-I has a secret miniature D4 from NK, to drop over America, if they try to do so?

harbans wrote:I'm actually a bit surprised that NASA invested 100m USD on one of it's 2 payloads. Thats an awful lot of faith to put in a mission that costs just 85m USd for India. Major Earth remote sensing satellites for launch India charges 10-11 million USD..(Italian one last year for example). I agree satellites do cost, but putting 100 m USD on a 1st Indian lunar mission is very optimistic for NASA..this will be the SINGLE biggest investment anyone has ever externally made in India's space programme.


I'm actually bit surprised that ISRO invested 5% of its budget on its moon mission and decided to do a charity and charged nothing for carrying 6 instruments from 5 nations, and gave them a complete free ride to Moon. For similar launches to Moon, USA wouldn't have allowed Russian or any other country's payload on its first Mission to moon, due to its paranoia with sharing of technology with others. So, I am surprised at Bravado of ISRO. I agree trust do cost, but letting 4 nations put their payloads on India's FIRST moon mission itself is a great confident step by ISRO. This mission alone has generated around 200 jobs in those 4 countries. And not to forget, massive investments by NASA and others in their local programme s to develop instruments for this mission. Maybe next time, NASA take a cue from Europeans and shed their shyness with dual-use technologies and start making satellites jointly with ISRO to reduce costs.



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