Mangalyaan : ISRO's Mars Orbiter Mission

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Victor » 21 Sep 2014 15:57


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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby member_28108 » 21 Sep 2014 18:45

bharats wrote:
prasannasimha wrote:Actually barring a crash we will still get data after the occult even if it is a flyby.
As far as the criticism of Mangalyaan it is practically a nonsensical argument. The amount learnt and information gained so far itself is hugely instructive. It is myopic to think that this hasn't been of benefit. While people argue of social uses dare I say socialistic uses let us not forget that these interplanetary missions have enthused and spiked recruitment to ISRO. Money is not the only attractant to a job and if ISRO's pay is less than private there must be something else to attract talent. Also don't forget the stupendous amount of learning in ranging, communication and autonomy that has already been acquired. Saying India is not ready for it is a specious argument. Those who dream and dare reap benefits. Talking of India's poor isn't ISRO generating income and to be rewarded rather than other sink holes in society. We waste millions to elect a$$ holes and crib when scientist struggle.
We spend millions and don't crib about cricket matches and film budgets but don't want to give pride and be proud of our scientists.



The review above is not a re- posting from firstpost, It is my critical evaluation of ISRO, its past and current activities and benefits. As an ardent fan of ISRO, I aspire to bring a perspective on what ISRO shall be doing and not to be doing.

My view, ISRO do not need to disguise Mangalyaan interplanetary probe as a science mission, where the knowledge potential its current payload might bring is by now existing in the international scientific community. At the same time I would not deny the fact that Martian interplanetary mission would bring challenges and learning to our engineers. And it is an un-denying fact that the scientific community in ISRO and external agrees that ISRO could have done better service to scientific community with better payloads had been our GSLV in service.

So, If ISRO need to sustain, a change in focus is the need of the hour. ISRO need to re-prioritize and bring back our rocket propulsion engineering to pace, and also reduce the communication transponders deficit in INDIA. There are other priorities as well which shall come before any interplanetary or sun or asteroid missions. Successful GSLV missions not only has a commercial gain and save foreign exchange in INSAT series satellite launch cost abroad but also more inland launches would give more trust and credibility to our space program partners from availing launch services from ISRO. I believe the soft achievements like Chandaryaan and Mangalyaan could never replace the above, as GEO capability simply would not exist for commercial purpose today. Also ISRO need more research to go on Unified Launch Vehicle (ULV) and semi-cryogenics and simply cannot lock best engineering minds on missions which give lesser Return on Investments (ROI) to society.

And profitability is only a matter of fact or point in time. For a skewed goal, the profitability would be lost in no time. What ISRO reaps today including our communication satellites and constellation of remote sensing satellites are outcome of meticulous planning and remarkable work done by great visionaries and leaders ISRO had in the past. All my point is now ISRO is losing or lost its focus; as deficit on transponder and launch capabilities are no longer appears to be on ISRO priority list, and is a cause of concern. Even ISRO state they are, it simply cannot; and we should also know that ISRO is a Centre of Excellence (COE), but that doesn’t mean that ISRO has access to have unlimited engineering minds. There is a deficit and we need to prioritize to sustain and lead.

And focus of my write-up was not to support Shri Madhavan Nair, though could not repudiate the fact that ISRO had good progress in rocket propulsion in his tenure. At the same time we cannot ignore the need a leader like Prof. Saish Dawan to bring glory and splendour back to ISRO.


Who says we are stopping the cryogenic program and GSLV- Let us not forget we have actually launched a satellite with the indegenous cryogenic engine.Also let us not forget the fact that propulsion is one aspect of a space faring engineering group.Advancess in all aspects allow us to repa better benefits.
Let us also not forget that these projects have actually attenuated attrition from ISRO and in fact have enthused brilliant young children to forsake their IIT seats for joining IIST with a goal to join ISRO and also for open recruitment offers(The current application ratio is > 1:1000).
Yes and where is it that you have evidence that ISRO has "forsaken" development of GSLV for the sake of these missions ? There ar e umpteen groups in ISRO with various roles and MOM is only devoting a minor component in the totality of ISRO's work which is visible.
If yu think they are so myopic let us not forget that they are planning for 30 years ahead by starting things like the space university where fundamental research right from undergraduate to postdoctoral level is going on and there is a paradigm shift in thinking.
What is externally visible is not everything and it is like an iceberg. Though there was failure of the cryogenic engine they did ultimately manage to do it- aks about the rocks in the cryogenic tanks and you will wonder who are friends are. No one is giving this technology for us and we have to develop it opurselves.it may take time but we need to attract also the best minds to do it and keep them enthused.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby member_28108 » 21 Sep 2014 19:15

Image

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby rsingh » 21 Sep 2014 19:17

BTW NASA's MAVEN thing is going live at 18:30 CET .

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby bharats » 21 Sep 2014 20:05

prasannasimha wrote:Who says we are stopping the cryogenic program and GSLV- Let us not forget we have actually launched a satellite with the indegenous cryogenic engine.Also let us not forget the fact that propulsion is one aspect of a space faring engineering group.Advancess in all aspects allow us to repa better benefits.
Let us also not forget that these projects have actually attenuated attrition from ISRO and in fact have enthused brilliant young children to forsake their IIT seats for joining IIST with a goal to join ISRO and also for open recruitment offers(The current application ratio is > 1:1000).
Yes and where is it that you have evidence that ISRO has "forsaken" development of GSLV for the sake of these missions ? There ar e umpteen groups in ISRO with various roles and MOM is only devoting a minor component in the totality of ISRO's work which is visible.
If yu think they are so myopic let us not forget that they are planning for 30 years ahead by starting things like the space university where fundamental research right from undergraduate to postdoctoral level is going on and there is a paradigm shift in thinking.
What is externally visible is not everything and it is like an iceberg. Though there was failure of the cryogenic engine they did ultimately manage to do it- aks about the rocks in the cryogenic tanks and you will wonder who are friends are. No one is giving this technology for us and we have to develop it opurselves.it may take time but we need to attract also the best minds to do it and keep them enthused.

arun wrote:ISRO spokesperson confirms delay of launch of GSLV Mk III . No new launch date indicated. The excuse for delay is the Mars Mission :roll: . Rather a lame excuse :( :
prasannasimha wrote:Not necessarily.They may need to use the Master control facility , ranging equipment and manpower to monitor the Mars insertion.Remember we are doing this for the first time (In bioth cases) and to bog down manpower may not be wise.Its not that they are playing Gilli Dandu here so they may want to allocate resources accordingly. Do you think it is wise to also launch the GSALV Mk III for the first time when they are also concentrating on the MOI ? Everyone forgets that these things ahve been done only a by a few nations and historically the smallest of errors have scuttled Mars missions so why cast aspersions ?

You have replied Arun with above text in ‘Indian Space Programme Discussion’, and you pointed out of a likely resource crunch at ISRO. These could either be people or facilities, but undeniably existing at ISRO. My point was exactly the same, when ISRO does more interplanetary travels, its priority changes, core competency projects like GSLV gets delayed. The local newspaper states ISRO says MOM as its priority and no response on date for GSLVMk3 launch was given.

I do agree to your view that ‘no one is giving this technology for us and we have to develop it ourselves. It may take time but we need to attract also the best minds to do it and keep them enthused'. But ISRO had IIST long before Mangalyaan was announced and there were enough triggers for young children to enroll IIST and join ISRO. Some of them were Satellite Recovery Experiments (SRE) and possible Human Space Program (HSP), that will enthuse minds larger than existing marginal interplanetary capability of ISRO. The truth is that you cannot have HSP until you have a mature space program in all dimensions, some ISRO is deficient now; the challenges are more and require GSLV to be man-rated in terms of reliability. Mangalyaan and Chandrayaan are low hanging fruits for ISRO and a certain hype created by Indian media. It neither creates amble scientific research nor the complex challenges to ISRO except deep space tracking-communication and orbital calculations. It is time for ISRO to realign itself and set priorities right.

If ISRO does more experiments like Mangalyaan, our core projects would forever be affected or delayed. That is the concern.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Victor » 21 Sep 2014 20:14

bharats wrote:My view, ISRO do not need to disguise Mangalyaan interplanetary probe as a science mission, where the knowledge potential its current payload might bring is by now existing in the international scientific

Did ISRO "disguise" Mangalyaan as a mere science project? If so, they did a bad job. I was under the impression, as I think a majority of Indians were, that it was an unabashed effort to achieve something very few have done successfully--enter Mars orbit--and NONE have managed before--to enter orbit on the first try. I suspect that very few Indians give a damn about a methane science experiment even if it has never been tried in the same manner before and has monumental repercussions on human history. Similarly, few cared or even knew that Chandrayaan discovered water on the moon but only that we had gone there. The Americans were not guided by the principle of adding to the "knowledge existing in the international scientific community" when they landed on the moon or even Mars, so should they not have gone and did they not learn anything at all from that effort? After all, they had millions of desperately poor people in their inner cities who could have been fed pizza for a week. The human race has never benefited from retrogressive bean-counting but has prospered enormously because it has done things only because they are hard, like climbing Everest or building the Eiffel Tower.
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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SwamyG » 21 Sep 2014 20:16

bharats: One thing you are missing is that motivation and inspiration works well with a mission and its accomplishment. Essentially humans, especially children, need a concrete manifestation for a better grasp. Moon remained a scientific, romantic, cultural and a religious symbol in the human mind for thousands of years. Mars and Sun offer similar symbolic motivations to the people. Like Rakesh Sharma is etched in the minds, Mangalyaan will be etched in the minds. Complex projects than MOM would not captivate the mind the same way; how much ever they are useful to the scientific community and the state. In long journeys, it is good to pick some low hanging fruits and energy bars :-) I hope ISRO does not stop working on other projects. They have never done that in the past.

You are worried and concerned that ISRO does not get distracted. Once in a while ISRO has to project success and brag about its accomplishments. So ensoy the current effort, allow yourself to be happy :-)

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SaiK » 21 Sep 2014 22:38


that reverse thrust animation would use the 440N engine correct? q: i expect we are reducing the speed.. do we know by how much? and what is/are-all the sensors and input parameters that plays in for this correction?

just trying to ask something better... than whining and biting my nails, and we get to focus on the mission.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby vina » 21 Sep 2014 22:39

Amber G. wrote:Vinaji - Some clarification. Hope this is useful.

The paths (trajectory) of Mangalyaan, and MAVEN are virtually the SAME in a general sense. When one does not burn fuel in the middle, then within a few percent or so, total time taken (about 10 months), total path travelled (about 700 Km), and shape of the trajectory (when it leaves earth's SOI (vicinity) and enters Mars's) is very similar. When drawn on scale,.. One trajectory will fit nicely on to other.

I know, I didn't mean a straight line literally, but rather a straight shot by Maven into an orbit towards mars rather than the approach used by Mangalyan to fire its' 440N engine at the perigee

MOM, saved fuel (compared to MAVEN) with innovative "earth raising orbits" and timing the fuel burn at most suitable time, and of course, having a highly elliptical and a little distant orbit around Mars...


That is exactly what I mean. Yes, the Atlas V delivered the Centaur V cryogenic upper stage ( a pretty massive beast in itself) along with Maven, and the Centaur stage did 5 minute burn (it is what a 100 KN vacuum thrust engine?) to throw Maven into that trajectory. Net result, Maven , arrives at Mars with nearly 100% of it's on board fuel intact so that it can go into a near circular orbit around Mars and stay there for a year or slightly more ( the Mass that reaches Mars is roughly 2000 kg I think). However, the mass fraction that gets to Mars out of the Atlas V is pretty poor.

Now , all I am saying is that with the same centaur stage NASA had done an Mangalyan like orbit raising and final burn to Mars, the mass fraction that could have gone to Mars could be higher (more fuel intact, more payloads , everything).

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Amber G. » 21 Sep 2014 23:01

SaiK wrote:

that reverse thrust animation would use the 440N engine correct? q: i expect we are reducing the speed.. do we know by how much? and what is/are-all the sensors and input parameters that plays in for this correction?

just trying to ask something better... than whining and biting my nails, and we get to focus on the mission.


The delta-V (planned) is about 1.1 Km/Sec (more accurate value, one can see from isro site - but this value of about a Km or so is needed for any kind of orbit insertion around Mars)

Using high-school math one can calculate the circular orbital speed around Mars to be about 3.5Km/sec or so (depending on height but it will not vary much ), and escape velocity about 5 Km/sec.. so delta-V needed is about 1.5 Km or less - if that is delivered at the perigee)...
(Ratio of escape velocity to circular orbit speed is sqrt(2) or 1.4 - and escape velocity is sqrt(2GM/R)
(M is mass of Mars and R is distance from the center of Mars, and G is gravitational constant)

(BTW, even if the delta-V delivered is smaller than 1.1 MOM may have more elliptical orbit but will orbit Mars - All simple physics onlee :) )

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Amber G. » 21 Sep 2014 23:24

ashokk wrote:Lots of interesting nuggets so quoting in full...
Mars Orbiter Mission is on stable trajectory: ISRO chief

Thanks. Nice. (There were a few points I wanted to make in my posts here, but above has made those points in a much more clear ways - and answer many questions)

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Amber G. » 22 Sep 2014 01:13

rsingh wrote:Pardon ? Is there any pic of known objects with background of stars? I missed that. I used to think that brightness contrast is so much that if you take pic of mars horizon or moon ………..you do not get stars in the same frame.

Did we misunderstand each other? (Because taking pictures of planets/objects with background of stars is routine)

For example, this picture is rather interesting :) .. (You can see stars in the background )
sat image of India (Edited: In line image removed)

Actually look at the moon, or Mars, or venus at any time you can see them, and you will see stars in the background. And you can take pictures, as I have done many many times, of such objects with the background of stars. Just try it, use a good digital camera, take a picture of the moon and you will be able to see stars in it. (I like the one I took of International space station while Space Shuttle was docking and I happen to see that beautiful site, so I took pictures with my ordinary digital cameras.)

In space or on Moon, where is there is no air/dust particles to scatter the light, seeing stars in the background, even when one can see sun, is not hard. (For camera it is easy - for human, you may have to shield your eyes a little, and give some time for eyes to adjust)..

Seriously, it is routine. This is how astronomers discover (and find their position/orbit accurately) of new planets/moons/astroids, comets etc. And oculation of stars by moon/planet, or transit of planet in front of Sun are important events for this reason. (Accurate value of Sun-Earth distance was first calculated by venus - transit)

This was the primary (if not the most accurate method) of navigation for space probes... now of course with the introduction of accurate atomic clocks, and radio-navigation etc we have many better methods for navigation....
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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby rsingh » 22 Sep 2014 03:02

Stars are still there. But when ever you are near brighter object, it is almost impossible to get in the same frame. That is why you do not see stars in any of the pic from moon. There is pitch black space in every pic taken by astronauts on moon. Astronauts or cosmonauts are not looking out of windows to determine their position ; they used special instrument to find their position visa-vi an hypothetical constellation. That has to be done when they are facing shadow side of the spaceship. Finally I am not very convinced by the pic you posted……..you can see the stars even through thick atmosphere (same brightness)and even on earth. It look like photoshop (a la 1970) or artistic rendering. Baki…….you are the guru log , who am I to understand the high quality fiziks. I just keep the facts simple and I tried to clear my doubts. Modern camera takniki is very sensitive and I think you have a point here.

Live HD from ISS Earth and space in one frame and not a single star visible.
http://www.nasa.gov/multimedia/nasatv/i ... B9O6VYihg0
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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Indranil » 22 Sep 2014 03:05

AmberG. I don't agree with the following line. Please correct me if I am wrong.
In space or on Moon, where is there is no air/dust particles to scatter the light, seeing stars in the background, even when one can see sun, is not hard. (For camera it is easy - for human, you may have to shield your eyes a little, and give some time for eyes to adjust)..

Actually if you are on that part of the moon where there is earthrise and/or sunrise, you won't be able to see the stars (though the sky is black). In general, if you are looking at the sky, where you can see the sun then you won't be able to see the stars. Additionally, if you are close to a planet and you can see the lit part of the planet (earth from moon), you won't see stars either.
Image
Image

You can see them in a specially designed camera with extremely small aperture and slow shutter speed, but not with the naked eye.


But then you can always see the stars, if there is no sun or sunlit part of a nearby planet in your view. This explains the picture that you posted. It is a long exposure shot (you can see the the star-trails and the glow in the atmosphere, which is 98% transparent) looking at the dark side of earth and in the direction away from the sun. Enjoy this beautiful video.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SSSalvi » 22 Sep 2014 04:10

1. In about an hour from now ( 00:59 GMT .. nearly 6:30 AM IST ) MOM would test the Martian Gravity. ( Yummy isn't it ) .. ( Sorry, a couple of months of US atmosphere have corrupted words. )
MOM will crossover 577000 Kms distance from Mars and will enter Martian gravity which will henceforth be more than Sun's gravity that it was riding on till then. All this happening to MOM while its friend of all these days, MAVEN, enters in Martian orbit at the very same time.

Just for the sake of 3rd point mentioned below: Right now MOM speed is 3.18 Kms/sec w.r.t. Mars ..( Mars speed of 25.73 - MOM speed of 22.58 ) which remains more or less constant upto MOI where it picks up to 3.88 kms/sec in a few minutes prior to MOI.

====

2. There are a few references that MAVEN and MOM re taking same path.

Paths are not SAME but are similar.

Image

======

3. Just to add some real numbers to AmberG 's post on reduction of Speed:

Image

A detailed look at dynamics of acceleration during this critical operation is shown in this graphic. ( numbers are in kms/sec/sec ) corresponding to sky blue curve. ( X axis is time axis from 0110GMT to 0310GMT of 24sep. )
Violet curve is the speed normalized to fit in this graph with that of acceleration. Actual speed variation shown corresponds to 3.88 km/sec at left to 5.89km/s at peak near center which falls to 4 km/s at left edge.

Also marked are the events of reorientation ( between red dots ) and retro rocket firing ( Between Green dots ) on acceleration curve.

Notice that the LAM retro action started at first green dot on left ( 0152 GMT ) .. it has tried to reduce the speed but the fall is more powerful, so MOM speed continues to increase despite retro action. This continues and for sometime eventhough the acceleration has started reducing ( blue line coming down ), the gathered momentum makes the craft to increase its speed for sometime. Finally however the thrusters succeed in reducing the speed ( reversal near center of violet line ) .. the thrusters are also turned off at that moment.( green dot near the center of graph ). Now the total operation of MOI is over.

AmberG has also brought out an important point: Once you enter Mars' gravity you will attain SOME orbit around it if you can reduce the speed to some extent . If your thrusters just don't activate only then you will go in a hyperbolic orbit of no return to Mars, If the thrusters act more than certain value only then craft would crash on Martian surface .. for all other values in-between it will take some orbit.

Incidentally, the point where speed reversal has taken place forms the lowest point near the surface of MOM prior to first perigee which would occur after the craft completes one revolution.
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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SriKumar » 22 Sep 2014 04:26

Too many nuggets in the post by ashokk of the interview with ISRO chief. Some parameters relevant for MOI:

The 'forward rotation' (starting at T-21 min.) takes 21 minutes to achieve. (So the LAM is fired as soon as the forward rotation ends. No time wasted.). When the LAM burn stats, it will decrease the velocity of the craft from 5.127 km/s at an altitude of 1847 km from Mars to 4.316 km/s. The burn will last 24 minutes.

The above is Plan A. If the LAM does not work out (LAM 'testing' on Sep 22nd for 4 seconds), plan B will be applied. The attitude thrusters will be used. Of the 285 kg of fuel, plan A will use about 250 kg, and if plan B is applied, it will use up about 281 kg. The rest of the fuel will be used for 'periaspsis corrections', and is seen as 'sufficient' even with plan B.

The picture of earth posted by Amber G. is interesting in another respect.
The orange line in the middle is the Indo-Pakistan boder fence, lit up at night. The spots of bright lights are cities (Islamabad, Delhi, Lahore etc).

http://www.thehindu.com/sci-tech/scienc ... 442082.ece
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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Victor » 22 Sep 2014 04:37

^ Thanks SriKumar. I was curious about that orange line in the pic-it is a fascinating view.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby vina » 22 Sep 2014 04:48

SSSalvi wrote:There are a few references that MAVEN and MOM re taking same path.

Paths are not SAME but are similar.

Brilliant Sir! Brings out perfectly your point that the transfer orbits are in a single plane and the orbit around Mars is carefully designed with the TMI out of earth inclined at the exact angle for that to be achieved.

Yes, this shows up in the difference between MoM and Maven's orbits when plotted in 3D, though in plan view, they seem nearly the same.

======
Incidentally, the point where speed reversal has taken space forms the lowest point near the surface of MOM prior to first perigee which would occur after the craft completes one revolution.


Hmm. So is that also the most efficient point to allow capture by Mars i?. The speed at the perapsis is the highest and hence would require the lowest reduction in speed (and fuel use by the LAM) ?

Would it have been possible design the mission such that the MoM follows an elliptic path from earth that reaches zero speed there abouts at the apiaxis of the desired orbit and then allow Mars to capture it ?Would that possibly have required less energy to boost from earth ?

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Victor » 22 Sep 2014 06:22

Maven MOI is underway and can be watched live on NASA TV here.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SSSalvi » 22 Sep 2014 06:37

2 minutes for the BURN aboard MAVEN !!!

Watching Watching

The wait for receiving back of 12 minutes is agonising

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SwamyG » 22 Sep 2014 06:45

link? is it on http://www.nasa.gov ? Nothing happening there, just two people talking.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SSSalvi » 22 Sep 2014 06:47

http://www.nasa.gov/multimedia/nasatv/index.html#

BTW ,, what action can one expect when you can't see anything from spacecraft ? Only numbers .. that too can reveal something after number crunchers do their job .. definitly no pichcher in near future

Burn itself is 30 minutes+
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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SwamyG » 22 Sep 2014 06:50

I have DISH, and it has NASA TV as well, so sitting with the kids watching.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Victor » 22 Sep 2014 07:07

Maven's burn duration will be determined by on-board accelerometers which will switch off the engines when an exact incremental velocity is reached. Too much velocity = Maven overshoots Mars, too little = Maven crashes into Mars or goes into unpredictable orbit. Mangalyaan has similar on-board accelerometers that will shut off the engines. Before the burn, Maven was traveling at appx 35k mph and after the burn it will be slowed to appx 20k mph in order to be captured. The Maven team has sent good wishes to their ISRO counterparts.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby PratikDas » 22 Sep 2014 07:12

Maven in Mars orbit.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SSSalvi » 22 Sep 2014 07:13

Burn off. Waiting for performace analysis

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SwamyG » 22 Sep 2014 07:13

MAVEN made it. Mangalyaan.....good luck. A few more days.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Victor » 22 Sep 2014 07:14

Yup, Maven just confirmed to be in Mars orbit.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby member_28108 » 22 Sep 2014 07:18

MAVEN entered into orbit :)

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Anant » 22 Sep 2014 07:20

Congrats NASA. Good luck ISRO!

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Victor » 22 Sep 2014 07:25

Next milestone is test fire of Mangalyaan main engine tomorrow. Good luck ISRO.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby member_28108 » 22 Sep 2014 07:32

Telling that we are deviating form our social goals because we are diverting tracking for etc for the Mars mission is also a bit specious.Do you think the rest of ISRO will stop working because MOM is being inserted ? There are hundreds of teams working on different things.I do not see how one project is going to collapse whole of ISRO. One the other hand if you read the news they have accelerated the launch date of one of our telecommunication satellites recently so satellite building is going full swing to meet the shortage in transponder capacity.Yes the GSLV was delayed but it was not just due to lack of scientific input but active sabotage by other space faring countries.

IIST was indeed started before Chandrayaan but the lead up was there and why was it started - due to difficulty in recruitment of appropriate dedicated staff. We need to attract talent.

The argument that ISRO should only concnetrate on social and not scientific programs is again specious as the argument as to why we need to have a space program when we dont have toilets etc etc. We are precisely behind because we did not engage in fundamental research and became a leader instead of a follower and we have to get out of that shackle.

One simple example till we launched Chandrayaan we did not have adequate knowledge of radiation and thermal hardening for our electronics - a lesson we would never have learnt till we launched it.The spin offs to other electronics were immense. Its not that we are just shooting into the sky - we are gaining vital knowledge for our other programs too.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Amber G. » 22 Sep 2014 07:33

After a 33-minute engine firing, mission controllers received acknowledgement at about 10:25 p.m. Eastern time that Maven was in orbit around Mars...

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Comer » 22 Sep 2014 07:52

I had thought MOM test firing / course correction was today

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Varoon Shekhar » 22 Sep 2014 07:57

http://www.thehindu.com/sci-tech/scienc ... sliderNews

Apologies if someone has already mentioned this, but MOM has now entered Mars' sphere of influence.


The Mars Orbiter has just entered the Martian neighborhood, the Gravitational Sphere of Influence of Mars

At about 7:17 am on September 24, the orbiter's engine will commence the burn to take the spacecraft into orbit about Mars according to ISRO. The engine, known as the Liquid Apogee Motor (LAM), is carried on a communication satellite so that it can be moved from the temporary orbit in which the launch vehicle places it to the appropriate operational locati

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby partha » 22 Sep 2014 07:58

saravana wrote:I had thought MOM test firing / course correction was today

Yes. 2:30PM.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Yayavar » 22 Sep 2014 08:19

Well done NASA. Hoping the best for Mangalyaan.
Nice article from a couple of days back :
http://www.nbcnews.com/science/space/maven-mom-orbiters-close-their-moments-truth-mars-n207616

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby member_28108 » 22 Sep 2014 08:35

SSSalvi can you please add an additional line /trajectory in your graph of the velocity profile if a burn had not taken place for comparison. It would be very nice for comparison.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby symontk » 22 Sep 2014 08:57

SSSalvi wrote:2. There are a few references that MAVEN and MOM re taking same path.

Paths are not SAME but are similar.



But won't the MARS path will be along the sun's equatorial path like earth or is it an tilted path around sun?

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SSSalvi » 22 Sep 2014 09:32

^^^

Here are details of how the orbits are inclined
Earth 0 deg
Mars 1.84 deg ( You may notice it in the diagram )
Maven ( HAD :) ) 2.04 deg
MOM 2.48 deg

You can imagine the Earth inclination in that diagram by noting the horizontal path ( undulations representing six orbits while raising the Earth orbit ) that MOM took before TMI ( Nov 2013 time tag )
Last edited by SSSalvi on 22 Sep 2014 09:41, edited 1 time in total.


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