Mangalyaan: ISRO's Mars Orbiter Mission

[Raja Bose]

That is a politically correct way of describing mispronunciation.

After battling people in US for 20 years when they say that our pronunciation of "schedule" is "incorrect", I try not to make the same mistake as them. Worse is when THEY try to teach US how to pronounce "Himalayas" .. ha ha.

Heh, I still pronounce schedule the way we SDREs have been originally taught. The only time anybody gave me grief about it is some MUTU desi who pretended he could not understand me.

[SaiK]

one can't argue how the brits did.. no? unless we have the sch-ematics drawn, done a brit sch-ool or a sch-olar in these sch-isms. i think we need to sch-edule our own sch-muck-giris. /ot

===========

most of the martian little rocks here have sharp edges.. high winds and and high speed dust erosion for millions of years. water should have evaporated into space owing to low G?

[Vayutuvan]

IIRC, schmuck is a Hebrew word (from Aramaic?).

[Raja Bose]

OK no more OT on angrezi, let's get back to MOM.

[member_28108]

Apologies if this has already been asked and answered. But, why is the photograph by MOM so blurry? Is it because it has not yet been calibrated once on station? Or, has the photograph not gone through its required processing yet?

Compare the first and second image.There may be calibration issues but actually the first picture is through a Martian dust storm. Check out that smudges which appear in the dark area Syrtis major- those are actually plumose streaks.Compare them with some older pictures and you then can see the clear arc of the plumose streaks which have changed direction due to the 'sand storm"

[member_28108]

Shalav Thanks. That means at least for now India is limited to exploring Moon, Mars, Venus, Mercury, and possibly Sun. Are Jupiter and Saturn within the reach of current generation Indian launch vehicles? IN that case, IM very HO, it is better to keep on perfecting satellite launch technology so that we can get remote sensing data for geological exploration for oil, minerals and water, data for weather modeling and prediction, agriculture and forestry, communication technology, and GPS. As I see it, those kinds of projects will give us more bang for the buck. While they are not as sexy as neelAmbara (blue sky) projects, they too are technically challenging and keep a large number of Indian scientists engaged in satisfying work.

Once we get the GSLV program running those things can be possible - of course when we plan those we need to use gravity slingshots as all such attempts do as currently no rocket in the world has the capability to directly escape suns gravitation field directly.The fastest launch was New Horizons (16.5 Kms/second) which is on the way to Pluto but the probe required a gravity slingshot wrt Jupiter.

[SSSalvi]

Mangal Ke Peechhey ky Hua??

Post MOI data is now available for MOM orbit.

MOM had 1st apo-apsis ( Max distance from Mars ) of 80823 kms on 25Sept 14:45 GMT and 1st periapsis of 423 Kms on 27Sept 03:28 GMT. So it completed 1st orbit at periapsis.

With the latest data reworked the MOI dynamics posted earlier. ( The drama that took place during MOI which happened behind Mars as far as Earth is concerned )



Initially we can see the increasing acceleration under the influence of Martian gravity.

As soon as retro rocket started @ 01:48:40 GMT, we can clearly see the sudden drop in forward acceleration from 0.89 to 0.137 m/sec/sec. This stops the previously increasing speed from 5.18 kms/sec to 4.38 kms/sec a drop of 0.8 Kms/s in speed over the burn duration.
Acceleration also drops from 0.137 to -1.55 m/s/s in this period.

As soon as the retro rocket stops @ 02:11:50 GMT the MOM regains its natural speed around Mars ( as its satellite ) and the acceleration which had fallen to -1.55 jumps to -0.73 m/s/s. and MOM starts its orbit around Mars assuming this point as periapsis.

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Just a passing remark:

Sometime back there was a discussion of whether the solar panels will withstand high speed at periapsis.

With the above figure try to figure out how sturdy must the design be to withstand sudden breaking from 18700 kms/hr to 15700kms/hr and vice versa.

[member_28108]

deleted

[member_28108]

The signal from MOM was received by the IDSN antenna at 11.35 am on Wednesday, approximately after about 3 ½ hrs of reception of radio signals at Canberra station in Australia, when the Mars Orbiter was visible over the Indian sub-continent.

[member_28108]

There was a discussion regarding biocantamionation and crashing into Mars.
The 2009 COSPAR Workshop on Planetary Protection for Outer Planet Satellites and Small Solar System Bodies


If there is only orbital planning it is a Category 3 mission. All probes to Mars are considered category III/IV

Category III includes certain types of missions (typically a flyby or orbiter) to a target body of chemical evolution or origin-of-life interest, or for which scientific opinion holds that the mission would present a significant chance of contamination which could jeopardize future biological exploration. Requirements consist of documentation (more involved than that for Category II) and some implementing procedures, including trajectory biasing, the use of clean rooms (Class 100,000 or better) during spacecraft assembly and testing, and possibly bioburden reduction. Although no impact is generally intended for Category III missions, an inventory of bulk constituent organics is required if the probability of inadvertent impact is significant.

If Impact is planned

Category IV includes certain types of missions (typically an entry probe, lander or rover) to a target body of chemical evolution or origin-of-life interest, or for which scientific opinion holds that the mission would present a significant chance of contamination which could jeopardize future biological exploration. Requirements include rather detailed documentation (more involved than that for Category III), bioassays to enumerate the burden, a probability of contamination analysis, an inventory of the bulk constituent organics, and an increased number of implementing procedures. The latter may include trajectory biasing, the use of clean rooms (Class 100,000 or better) during spacecraft assembly and testing, bioload reduction, possible partial sterilization of the hardware having direct contact with the taget body, and a bioshield for that hardware, and, in rare cases, a complete sterilization of the entire spacecraft. Subdivisions of Category IV (designated IVa, IVb, or IVc) address lander and rover missions to Mars (with or without life detection experiments), and missions landing or accessing regions on Mars which are of particularly high biological interest.

for sample return missions

Category V pertains to all missions for which the spacecraft, or a spacecraft component, returns to Earth. The concern for these missions is the protection of the Earth from back contamination resulting from the return of extraterrestrial samples (usually soil and rocks). A subcategory called "Unrestricted Earth Return" is defined for solar system bodies deemed by scientific opinion to have no indigenous life forms. Missions in this subcategory have requirements on the outbound (Earth to target body) phase only, corresponding to the category of that phase (typically Category I or II).

For all other Category V missions, in a subcategory defined as "Restricted Earth Return", the highest degree of concern is expressed by requiring the absolute prohibition of destructive impact upon return, the need for containment throughout the return phase of all returning hardware which directly contacted the target body or unsterilized material from the body, and the need for containment of any unsterilized samples collected and returned to Earth. Post-mission, there is a need to conduct timely analyses of the returned unsterilized samples, under strict containment, and using the most sensitive techniques. If any sign of the existence of a non-terrestrial replicating organism is found, the returned sample must remain contained unless treated by an effective sterilization procedure. Category V concerns are reflected in requirements that encompass those of Category IV plus a continuous monitoring of mission activities, studies, and research in sterilization procedures and containment techniques.

[UlanBatori]

Q1: How many drawings do u think were required to develop and build this mission? Answer depends on how much of the mission was assembled from pre-existing parts, in which case only assembly drawings may have been needed as new.

I am trying to get a handle on the magnitude of the task starting with the actual engineering time involved in preparing and approving the drawings, up to receipt at the launch pad. Much of this may be computer-based drafting, but still a lot of time is needed for CAD.

Obviously a stellar example of successful System Design and project mgmt.

Q2: (since this is MIL dhaga): What is the equivalent CEP of this?

[SriKumar]

Mangal Ke Peechhey ky Hua??


Initially we can see the increasing acceleration under the influence of Martian gravity. As soon as retro rocket started @ 01:48:40 GMT, we can clearly see the sudden drop in forward acceleration 0.89 to 0.137 m/sec/sec. This stops the previously increasing speed from 5.18 kms/sec to 4.38 kms/sec a drop of 0.8 Kms/s in speed. Acceleration also drops from 0.137 to -1.55 m/s/s.

As soon as the retro rocket stops @ 02:11:50 GMT the MOM regains it natural speed around Mars and the acceleration which had fallen to -1.55 jumps to -0.73 m/s/s. and MOM starts its orbit around Mars assuming this point as periapsis.

Couple of quick questions....what is the speed in the plot relative to? Surface of Mars? Some other reference point? Any idea how this was measured? Or was speed 'merely' derived from the acceleration (in which case, does the acceleration represents the behavior of an onboard accelerometer)? Amber G. had once mentioned doppler (radar) to measure velocity relative to surface of Mars.

[TSJones]

one can't argue how the brits did.. no? unless we have the sch-ematics drawn, done a brit sch-ool or a sch-olar in these sch-isms. i think we need to sch-edule our own sch-muck-giris. /ot

===========

most of the martian little rocks here have sharp edges.. high winds and and high speed dust erosion for millions of years. water should have evaporated into space owing to low G?

There may very well be water on Mars although down in the ground. We don't know the extent yet. Gravity is not the problem on Mars. it is the lack of a strong magnetic field like what Earth has. Mars has a weak magnetic field allowing Solar winds and Galactic Cosmic Rays to directly bombard the Mars atmosphere and surface. A number of scientists now think that over the eons this has eroded the atmosphere away and stopped any formation of life. According to Bob Berman in his book Zoom, if you fear radiation don't even think of going to Mars. Some scientists say just two years on Mars can destroy 13% of your brain cells. Some scientists say 40%!

Shmuck comes from Yiddish and it is not a very nice word.

[member_20292]

Q2: (since this is MIL dhaga): What is the equivalent CEP of this?

GORGEOUS question.

As a corollary of the MOM, I'm sure China, and TSP would have gotten the message about indian missiles accuracies.

Eleven Jinping / NawazShareef's bottom's just got tattooed with a very large, imaginary , bull's-eye.

[SSSalvi]

Earlier figure has been modified by including the same parameters from just before the completion of insertion orbit to some portion of next orbit. ( Dotted lines )



Notice how the transition during MOI ( solid lines from earlier figure ) have changed to Martian orbit after MOI.

The dotted lines represent a regular Martian orbit and one can notice how nice they match with the later portion of solid lines.

==============

@ Srikumar

1. MOM has a speed varying from .22kms/sec at apo-apsis to 4.6 kms/sec at peri-apsis. Mars surface rotates at .24kms/sec.

So exact speed can't be described as a single figure althogh we can say that near the MOI and peri-apsis the speed is about 4.6 kms/sec because Maartian surface speed is just ,24 kms/sec.

2. In my figure, I have derived acceleration from speed values which are out of the result of orbit calculation giving X,Y,Z coordinates and xdot, ydot and zdot as velocity components.

3. The on-board systems calculate the craft position using stars ( one of the method ) and the speed ( I think ) is derived from it. I do not know whether speed is measured or how.

[member_28108]

Is there any precession of the mars orbit of MOM ?

[venkat_r]

Not mispronounce but pronounce it differently.

That is a politically correct way of describing mispronunciation.

Ha ha - that is also called having an accent - err what is a auk-shunt!

[SSSalvi]

^^^
^^^
The MOM orbit appears to be sun-synch ( but nowhere there is a mention about it ) .

I found it to be excatly 3 martian days

so it may be that 3 orbits will bring the satellite back to same position.

But this is just a quick counting on fingers.. can't say about correctness.

[anupmisra]

IIRC, schmuck is a Hebrew word (from Aramaic?).

Schmuck is a Yiddish word. Close.

[Amber G.]

Earlier figure has been modified by including the same parameters from just before the completion of insertion orbit to some portion of next orbit. ( Dotted lines )



Notice how the transition during MOI ( solid lines from earlier figure ) have changed to Martian orbit after MOI.

The dotted lines represent a regular Martian orbit and one can notice how nice they match with the later portion of solid lines.

==============

@ Srikumar

1. MOM has a speed varying from .22kms/sec at apo-apsis to 4.6 kms/sec at peri-apsis. Mars surface rotates at .24kms/sec.

So exact speed can't be described as a single figure althogh we can say that near the MOI and peri-apsis the speed is about 4.6 kms/sec because Maartian surface speed is just ,24 kms/sec.

2. In my figure, I have derived acceleration from speed values which are out of the result of orbit calculation giving X,Y,Z coordinates and xdot, ydot and zdot as velocity components.

3. The on-board systems calculate the craft position using stars ( one of the method ) and the speed ( I think ) is derived from it. I do not know whether speed is measured or how.

Thanks for above comments..

To add -
- The speed/distance formula (v = sqrt(2/r-1/a) ) is very nice. This is all you will need to get fairly accurate values. (See this or this for detail...
(These results are wrt to Mars (center of mars - not the surface, surface spins in about day)

- To measure position, (apart for old fashioned way of looking at stars), easiest method is very similar to how GPS in your car measures your location. Though MOM does not have an atomic clock, now a days it is very easy to get the same accuracy by synch-ing it using coherent standard frequencies (and signals) from ground stations.

- Thanks for noticing (I did not notice it first) that orbital period of MOM is 3xMars spin.. (not exact but within 5%) .. (Mars - spin rate is 24.6229 hours).
(Due to the fact that the orbit inclination is 150 degree, and the orbit is ellipse, the angular movement of the MOM is far from uniform)

- One can easily calculate velocity.. (just "differentiate" the position), but a direct method for radial velocity is very easy and accurate. Essentially it is just nothing more than listen to a known accurate frequency whose source you know)

[Amber G.]

^^^
^^^
The MOM orbit appears to be sun-synch ( but nowhere there is a mention about it ) .

I found it to be excatly 3 martian days

so it may be that 3 orbits will bring the satellite back to same position.

But this is just a quick counting on fingers.. can't say about correctness.

So it seems that, it will take about 18 hours 24 minutes.. on average - from one MOMrise to the next .

BTW, SSSalviji - if you get a chance, can you post the position of the nodes of the MOM's orbit. TIA
(So that I can calculate the position at a given time on my own)

[Amber G.]

Is there any precession of the mars orbit of MOM ?

What do you mean? (I know the usual meaning of precession (say as in axial precession of a body) but can you clarify exactly what do you mean by "of the mars orbit of MOM"? )

[SriKumar]

1. MOM has a speed varying from .22kms/sec at apo-apsis to 4.6 kms/sec at peri-apsis. Mars surface rotates at .24kms/sec.

So exact speed can't be described as a single figure althogh we can say that near the MOI and peri-apsis the speed is about 4.6 kms/sec because Maartian surface speed is just ,24 kms/sec.

2. In my figure, I have derived acceleration from speed values which are out of the result of orbit calculation giving X,Y,Z coordinates and xdot, ydot and zdot as velocity components.

3. The on-board systems calculate the craft position using stars ( one of the method ) and the speed ( I think ) is derived from it. I do not know whether speed is measured or how.

Thank you.

[SriKumar]

To add -
- The speed/distance formula (v = sqrt(2/r-1/a) ) is very nice. This is all you will need to get fairly accurate values. (See this or this for detail...
(These results are wrt to Mars (center of mars - not the surface, surface spins in about day)

- To measure position, (apart for old fashioned way of looking at stars), easiest method is very similar to how GPS in your car measures your location. Though MOM does not have an atomic clock, now a days it is very easy to get the same accuracy by synch-ing it using coherent standard frequencies (and signals) from ground stations.

- Thanks for noticing (I did not notice it first) that orbital period of MOM is 3xMars spin.. (not exact but within 5%) .. (Mars - spin rate is 24.6229 hours).
(Due to the fact that the orbit inclination is 150 degree, and the orbit is ellipse, the angular movement of the MOM is far from uniform)

- One can easily calculate velocity.. (just "differentiate" the position), but a direct method for radial velocity is very easy and accurate. Essentially it is just nothing more than listen to a known accurate frequency whose source you know)

Thanks. OK, for radial velocity the doppler effect could be used, with the signal being generated from the craft itself in absence of a ground station on Mars. For tangential (=orbital) velocity I assume doppler will not do the trick, so is there way to measure orbital velocity? I suppose it could potentially be calculated if the surface geometry of the planet is known accurately, thereby permitting the derivation of the tangential velocity from radial velocity (which is measured with doppler). W.r.t. the 'gps way of measuring position', I assume this method would not be available to MOM when it is on the far side of Mars (not sure if it could be used even when there is line of sight to earth with its 3 tracking stations, maybe 1 visible at any given time).
Added later: the Indian Deep Space Network shows many stations, not just 3. So, with a line-of-sight, MOM can get it velocity from earth stations.)

[Vayutuvan]

Once we get the GSLV program running those things can be possible

I think you misunderstand my question (it was rhetorical - looks like you did not get it). The point is that let the big $$$ chase the deep space exploration at the cost of healthcare but India should concentrate on perfecting near space and other tech that benefits uhmanity in genral and specifically the Indians and SAARC nations which look to India for leadership. Yes I am anti-(big boondoggle)science which helps nobody but Relax and Dream kind of R&D people (AKA futurologists/futurists) and I am proud to be so until somebody actually proves to me beyond doubt that my tax dollah should be spent on the assorted LIFs and in-silico nuclear explosions.

[member_28108]

Once we get the GSLV program running those things can be possible

I think you misunderstand my question (it was rhetorical - looks like you did not get it). The point is that let the big $$$ chase the deep space exploration at the cost of healthcare but India should concentrate on perfecting near space and other tech that benefits uhmanity in genral and specifically the Indians and SAARC nations which look to India for leadership. Yes I am anti-(big boondoggle)science which helps nobody but Relax and Dream kind of R&D people (AKA futurologists/futurists) and I am proud to be so until somebody actually proves to me beyond doubt that my tax dollah should be spent on the assorted LIFs and in-silico nuclear explosions.

If we do not lead and explore then we will miss out technologies and will looose out. Simple example the experience gained from MOM will be used to develop greater autonomy in near earth satellites, better ranging etc. Our DSN receiver is selling DSN ranging for $3500/ min of ranging and so on and so forth-The spin offs are more when we invest in science.let us not forget that you also want to attract talent and not have a bunch of mindless workers which will kill any program.

[member_28108]

Is there any precession of the mars orbit of MOM ?

What do you mean? (I know the usual meaning of precession (say as in axial precession of a body) but can you clarify exactly what do you mean by "of the mars orbit of MOM"? )

Does it(the orbital path) precess around Mars

[Bade]

What is useful science or not has to be decided by the practitioners of science and not the tax payers, even if the tax payer money is the predominant support base for all scientific pursuits. If politicians and soothsayers are going to draw the line for good and bad science, there will be even less smart people interested in pursuing science projects.

If it is all about end use, why should I forsake a $200k pay for a fourth of that amount while selecting a career path as a young man.

[member_28108]

What is useful science or not has to be decided by the practitioners of science and not the tax payers, even if the tax payer money is the predominant support base for all scientific pursuits. If politicians and soothsayers are going to draw the line for good and bad science, there will be even less smart people interested in pursuing science projects.

If it is all about end use, why should I forsake a $200k pay for a fourth of that amount while selecting a career path as a young man.

This toilet versus satellite debate of various forms has been beaten to death. Some elegantly asking of'social uses versus science" to make it more sophisticated.They all forget the spinoffs to other areas.

[sanjaykumar]

The response is very simple:When Kennedy made his commitment to put a man on the moon (1962), one in three Americans was classified as poor. It would appear, prima facie, that a space program reduces poverty.

[Vayutuvan]

I think all of you are missing the point - most of all Bade saaheb. Sire, I am against big boondoggle science - not fundamental table top science research that can be done without spending (non-existent) tax monies on SETI and the political pork barrel Solindra and what is whatisits face company being pushed by Mr. Vinod Khosla.

Sanjaykumar: What what what? Statistical bhasha mein boliye sir. Do you really believe that there are spin offs from man on the moon? Do you believe that without putting a man on the moon, comm and remote sensing satellites could not have been developed? Yeah, what all we have to show today from JFK's "man on the moon" initiative is the that space oice cream or some such tacky stuff that gets sold in all Disney and 6 flag, and Shamu sea worlds.

prasannasimha ji: In what way 0.3 m/s is "nominal" saab? Please talk in relative error terms not absolute, sir. Absolute error means nothing. To whit, if the target velocity were to be 1.0 unit/s would you say that 0.3 units/s is nominal?

Too much of this "I open a cadaver and can see the insides from which I can figure out how I can open up a live human being and fix her" being applied to "Oh kay - let me open up this thingummy called a chip and see how it works - may be there are a few small whatchammacallits are sitting in there spinning small gears so I will see it with a small microscope and reproduce". All of us know how that is going to end.

[member_28108]

Matrimc you are nitpicking.We knew both the required velocity and perigee and the deviation from it and the 0.3 is in refetence to it.Nominal as used here is within their declared parameters. X standard deviations away from their predicted. You are equally wrong in neglecting the absolute value. It is both the absolute value and deviation from a predicted value that is required. There is nothing in the world beyond surety that you will die that is absolute so we give a range because of inherent errors of measurement. Ot is not me declaring that the orbital path was "nominal" but the announcement made when orbital parameyers were announced which was in their required and acceptable range.

[member_28108]

http://english.stackexchange.com/questi ... tolerances

Use of nominal in aerospace applications refers to within acceptable limits.

There have been enough cost benefit analyses done to show space exploration is beneficial .

[member_28108]

Funny :you allude to our space program being screwdrivergiri

[Vayutuvan]

hakim saheb: There is no science if there is no nitpicking. It is like somebody calling a ventricle a ventriloquist then of course one would nitpick, wouldn't she?

What is with X-sigma deviation etc. from a sample of one? 6-Sigma metrics will work in some wishy-washy Fed initiatives, USAID, Sociology, Piskology counzelling, CMU software blah certifications, and NASA big "vision" projects which have the chance of finding a snowflake in hell. NASA's PR budget probably outstrips India's entire space budget for last five years. They produce supercomputer ray traced brochures by the bushel which as soon as they are received in researchers' mailboxes are immediately and unceremoniously dumped into trash - not even recycled trash. But then in the US big businesses and scientific establishments waste lots and lots and lots of money. The thought I am putting forward is that India cannot afford the kind of Keynesian "dig and fill" supply side approach to scientific research that has been popularized and is being practiced in the west generally and in the US specifically.

If, in your opinion, only big science is good science, I would end this discussion right now and say good night.

[Vayutuvan]

Funny :you allude to our space program being screwdrivergiri

If you are referring to me, I would challenge you to show me where I said that.

At the outset let me put it on record (not that it matters in the larger scheme of things) that I am extremely happy and very proud of the achievement on such a small budget.

That said I also feel that there is no need to waste money on SETI and deep space probes and such which are going to give India fifteen minutes of fame in some obscure internet sites which hype space exploration this and space exploration that forgetting that FTL travel is impossible and the nearest star is ~4 light years away.

The running joke in one big midwest university Physics department is every year the freshman come into the Physics lab and ask where they can checkout a few light sabers which they would like to use in their "Creative Anachronism" or their fencing clubs.

[member_28108]

Martin you seem to be confused when you say how can we get x sigma with asample of one. Please go back to statistics (and yes I have a formal training in it if you ask my qualifications apart from my medical degree) .What is referred here us built in design tolerance ranges of a system which can be expressed in so many standard deviations from the normal (in this case the predicted ideal value) . Sigma or Z value or the log it number can be used as a method to define this range assuming a normal distribution. Once we have an observed value it can be defined as x sigma distances away from the "ideal " or predicted value and if it is within the predefined range it is considered acceptable or nominal. If you think that this is only used in engineering to be thrown into the dust bin as you say I the hakim as you called me use it in cardiac surgery daily but then I digress and yes name calling and ranting does not lend to cogent discussion.

[member_28108]

http://freakonomics.com/2008/01/11/is-s ... cs-quorum/
http://www.planetary.org/blogs/emily-la ... /3317.html
If you want it in pure dollar terms the benefit for every dollar spent on the Appollo mission was 8$.
Isro is generating a profit not a loss.

[Vayutuvan]

I bow out. No point really since there is an impedance mismatch or a difference in wavelengths. Call it a weakness in my being trained as a reductionist.

But I would leave you with one question. Do you think that there are hi challenges in near space exploration and no challenges in other areas of science, however you want to define science? What kind of resources do we need to tackle those challenges vs. what we need to spend on a wild goose chase of worm holes, zero point energy, and generation of electricity by looping several mile long cable round a freely spinning magnet in space or a space elevator or terraforming on the large on moon/mars? Whatever for?

[member_28108]

There are enough challenges and encourage their pursuit. Don't cut the leg to spite the hand. Its like arguing why develop cardiac surgery and neurosurgery in India because children are dying of diarrhea diseases. Both are important. If you don't have a TIFR and Raman Institute where will those researchers go. investment in deep space and y't have astrophysics people and nurture them will we be better (for as a nation. Why do we need IT engineers when our problem is irrigation - lop of all the ITBT people and have only civil engineers.Reductionism is nice as an arguing point but becomes absurdum if carried too far. Hasn't this program enthused our youth, spurred associated industy,provided employment and value addition to the country. Neglecting pure sciences will be the downfall of a nation. I will give a simple example. I acytually give lectures in engineering institutes and international biomedical /health care companies who wish to do basic work in engineering and funny thing is the biggest stumbling block I find is the lack of kbowledgevwrt basic sciences -that is the basic stumbling point for Rand D in our country. You ask why should we do research on general relativity and well if we don't what will happen wrt time keeping on our IRNSS satellites? Similarly the benefits on ranging etc etc have been immense. A myopic view gets us only that far. If we want to progress as a nation we have to make bold strides. Not stick to whatever level of toilet argument. As a simple example the deep save mission allows us to market ranging data at 3500 $ per minute PR customer . Isnt that an earning and a spinoff from that investment in depth space exploration which we would not have an incentive to build but for these projects. Beam wave antennae were built and the spin off us antennae development for other satellite purposes.