Mangalyaan: ISRO's Mars Orbiter Mission

partha · Post by **partha** » 04 Dec 2013 03:09

A Tale of Two Cyclones

1999 - Category 5 Cyclone 05B hits Eastern India: 10,000 deaths
2013 - Category 5 Cyclone Phailin hits Eastern India: c.50 deaths

I am 400% sure when INSAT 3D was launched (which helped save so many lives) some JNU jhollawallah wrote an op-ed in The Hindu ranting about how India is spending millions of dollars on space technology when 99.99% of the people are living on less than 1 paise a day.

Varoon Shekhar · Post by **Varoon Shekhar** » 04 Dec 2013 07:39

"Spacecraft has traversed beyond the Sphere of Influence (SOI) of Earth extending about 9,25,000 km at around 1:14 hrs (IST) on Dec 4, 2013."

From the ISRO site.

member_28108 · Post by **member_28108** » 04 Dec 2013 09:55

vnmshyam wrote:
prasannasimha wrote:They talk of reducing in even grams(as one pound requires roughly 10,000 US $.When my Son took part in ISRO's rover competition(He won the prize ) they measured their rovers and they took best mass to throw and run ratio(The rovers had to do a series of tasks and the lowest weight and best performer were selected).All the rovers had to be made from the parts given - all mechanical - planned for back up systems if electronics fail).Adding camera's etc appear intuitive but costs ramp up. Also we cdo not know if they actually ahve some cameras for mission critical monitoring which they may not release publicly.
Good to know and congrats, saar. How old is your son, if you don't mind my asking? Could you also provide some additional information on the rover?

My son is in 12 the standard. He was in 9 the standard when he won it (if I remember right) . He also won the ISRO quiz and science aptitude contest for 3 years in a row. The rover competition was a team event. 3 a team. There was a defined obstacle course shown to them at the starting. Only self developed mechanical sensors were allowed. They had to course correct avoiding side walls and obstacles. Finally hit an end wall and throw a weight. They were scored on time traversed, weight and greatest throw of the given weight. Only 3 teams reached the final wall and my sons team was the first, threw it farthest and was the lightest. He also was given a personal interview with TK Alex! They particularly liked one contact sensor and a part of the transmission and it actually beat the reference model built by ISRO ! This really excited both the team and the ISRO scientists ! One of them phoned me to get permission for the interview with TK Alex and he was very happy.
Coming back to the camera discussion - the points for weight budgeting was very high and they had to account for every gram as this was considered a part of the payload - this was emphasized by the ISRO Scientists there when they were explaining how the assessment would be made.

Pratyush · Post by **Pratyush** » 04 Dec 2013 10:08

My fingers are crossed and am hoping for successful orbit insertion in september.

member_28108 · Post by **member_28108** » 04 Dec 2013 10:14

It crossed 1 million kms this morning

NRao · Post by **NRao** » 04 Dec 2013 10:16

Keep all fingers crossed. However be aware that MOM has two shots at it, unlike others who had/have a single shot.

Abhaey · Post by **Abhaey** » 04 Dec 2013 11:24

SBajwa wrote:Good Article Abhaey!!

Thank you!

Abhaey · Post by **Abhaey** » 04 Dec 2013 11:25

vnmshyam wrote:
Abhaey wrote:My latest article may be of interest to you:

Mars is a 'Red' Herring: Why India's Space Programme Is a Global Role Model
Abhaey, good article.

I have just read your other posts regarding India. Wonderful read!! My compliments and please do complete the remaining 2 posts regarding the matter.

Thank you so much! I am sorry about the delay with the other two - I have been travelling relentlessly but they will be completed in due course

member_28108 · Post by **member_28108** » 04 Dec 2013 16:53

partha wrote:
A Tale of Two Cyclones

1999 - Category 5 Cyclone 05B hits Eastern India: 10,000 deaths
2013 - Category 5 Cyclone Phailin hits Eastern India: c.50 deaths
I am 400% sure when INSAT 3D was launched (which helped save so many lives) some JNU jhollawallah wrote an op-ed in The Hindu ranting about how India is spending millions of dollars on space technology when 99.99% of the people are living on less than 1 paise a day.

Don't forget Praful Bidwai - he eptiomizes the standard Bearded Jholawalla we used to ahve in college days.There is also the NGO types pitching in like that Dreze fellow.They would like us permanently working in some Gulag.

member_28108 · Post by **member_28108** » 04 Dec 2013 17:04

I am wondering how MOM has two shots at Martian insertion.Once it enters the sphere of influence it has to decelerate to be captured - fly by or crash. How will it get two opportunities if it fails to "capture" ?

Victor · Post by **Victor** » 04 Dec 2013 18:24

Abhaey wrote:My latest article may be of interest to you:

Mars is a 'Red' Herring: Why India's Space Programme Is a Global Role Model

Nice article. The following is useful data on Mangalyaan's cost:

* 2.1 % of India's c.$3.5bn aid contributions to other nations
* Less than 2% of the estimated £2.5bn in salaries paid to UK employees by Indian companies
* 0.3 % of India's $24bn IMF bailout contribution to the Eurozone crisis
* 0.02% of India's total government expenditure in 2013

Karan M · Post by **Karan M** » 04 Dec 2013 18:28

Abhaey wrote:My latest article may be of interest to you:

Mars is a 'Red' Herring: Why India's Space Programme Is a Global Role Model

Superb. Crisp and well referenced.

Abhaey · Post by **Abhaey** » 04 Dec 2013 19:11

Victor wrote:
Abhaey wrote:My latest article may be of interest to you:

Mars is a 'Red' Herring: Why India's Space Programme Is a Global Role Model
Nice article. The following is useful data on Mangalyaan's cost:

* 2.1 % of India's c.$3.5bn aid contributions to other nations
* Less than 2% of the estimated £2.5bn in salaries paid to UK employees by Indian companies
* 0.3 % of India's $24bn IMF bailout contribution to the Eurozone crisis
* 0.02% of India's total government expenditure in 2013

Thank you - I chose these cost comparisons in particular because elements of the Western media, in Britain most of all, always relate India's space projects - which have nothing to do with unwanted aid in any case - to their aid handouts. My choice of comparisons is to politely show a mirror as to how offensive, irrational and factually untenable their commentary is. Here are just two of the many, many examples:

India sends a spaceship to Mars after UK gives £280million in aid
India sends rocket to Mars to show off its 'technological ability' as part of its $1billion a year space programme (but country will still receive British aid until 2015)

However - for every Brit who loves to talk India/China/Africa down, there is always a genuinely Great Brit who sets the record straight:

India is heading for Mars: it doesn’t need British aid money to pay the bills

I look forward to the day when they shape the mainstream view!

Abhaey · Post by **Abhaey** » 04 Dec 2013 19:14

Karan M wrote:
Abhaey wrote:My latest article may be of interest to you:

Mars is a 'Red' Herring: Why India's Space Programme Is a Global Role Model
Superb. Crisp and well referenced.

Thank you!

sudhan · Post by **sudhan** » 04 Dec 2013 20:35

Excellent articles, Abhaey ji!

The sheer amount of hatred aimed at India and Indians in the comments section of some of these articles is unbelievable..

Supratik · Post by **Supratik** » 04 Dec 2013 20:53

Very well written article - Abhaey.

Abhaey · Post by **Abhaey** » 04 Dec 2013 21:04

sudhan wrote:Excellent articles, Abhaey ji!

The sheer amount of hatred aimed at India and Indians in the comments section of some of these articles is unbelievable..

Thank you, Sudhan Ji. It is very vicious, but it will slowly change, and we must all play our part in correcting the disinformation/misinformation out there. If any of you can help us spread our positive message and deal with this disinformation, please get in touch.

Abhaey · Post by **Abhaey** » 04 Dec 2013 21:04

Supratik wrote:Very well written article - Abhaey.

Thank you, Supratik.

vdutta · Post by **vdutta** » 05 Dec 2013 00:10

I have few questions. It may be very silly for you guys but here it goes

1. How do they track the spacecraft? Do they use radars? I am not sure if radars are that powerful plus earth keeps on rotating so we cannot have a line of continuous sight.

2. How do they measure speed of the spacecraft.

3. Lets say even if the spacecraft sends back signals which help us to triangulate it but how does it help us. There are no reference points in empty space so how do they figure out where exactly it is in the 3 dimension and where it needs to go.

4. Lastly what happens to the craft after it served its purpose. Do they crash it on the planet for further studies or move it out of mars orbit. I think it will be cool if they crash it with cameras sending live feed. Other orbiters can take pics of dirt it kicks up which can be used for further studies.

Bonus question: Mangalyaan needs to travel over 750 million kms in 10 months, but media reported that it will travel a million km a day, that means it will cover over 300 million kms in given time, so are they going to increase its speed at some point? Also today i read on news that it is 0.95 million km away as of today. Shouldnt it have covered 4 million kms in last 4 days since it left earth?

Thanks in advance.

SBajwa · Post by **SBajwa** » 05 Dec 2013 02:52

by vdutta
Bonus question: Mangalyaan needs to travel over 750 million kms in 10 months, but media reported that it will travel a million km a day, that means it will cover over 300 million kms in given time, so are they going to increase its speed at some point? Also today i read on news that it is 0.95 million km away as of today. Shouldnt it have covered 4 million kms in last 4 days since it left earth?

Think of the Space travel as a relative to something. While Manglayan is traveling so is its destination (Mangal) and what's the speed relative to that destination (Mangal) who is also traveling at some other speed.

What is the speed of Manglayan relative to its Destination.
What is the speed of Manglayan relative to its Origin.

VikramS · Post by **VikramS** » 05 Dec 2013 02:55

Abhaey wrote:My latest article may be of interest to you:

Mars is a 'Red' Herring: Why India's Space Programme Is a Global Role Model

Oh I did not know you are here on BR

; saw you on HuffPo and Twitter.

member_28108 · Post by **member_28108** » 05 Dec 2013 07:16

Tracking - distance is by using ranging by sending a pulse to the spacecraft and it responding and measuring the time lag. Velocity is by measurements. Doppler and delta differential one way ranging (delta DOR).I asked in the ISRO website about what they will do after its mission life but they did not give an answer.The international space treaty doesn't allow you to just crash something to avoid contamination (it has to be sterilized and certified) .They may place it in a graveyard orbit or give it some final burn towards some other object as a flyby.

member_28108 · Post by **member_28108** » 05 Dec 2013 07:23

From the German Wikipedia site
Delta-DOR method
The Delta-DOR method (English: Delta Differential One-way Ranging) for interplanetary navigation is based on a simple but effective idea. Two widely spaced receive antennas simultaneously track a spacecraft and thereby determine the time difference between the time instants at which the signal arrives at the two stations. The art to determine this difference is one-way differential range (DOR). Theoretically, this difference depends only upon the positions of the two antennas and the observed spacecraft. However, there are a number of confounding factors, they must, for example, the radio waves through the troposphere and the ionosphere , they are disturbed by the plasma in the solar wind and the clocks of the base stations are inaccurate. The Delta-DOR method corrects this error by changing the direction of a quasar is used for correction (within 10 °) near the spacecraft.
The direction of the quasar is by prior measurements very accurately known with an accuracy of only 50 billionths of a degree. The distance to the spacecraft is calculated by measuring the time it takes for a radio signal to the probe and to the earth. By measuring the Doppler shift of the signal, the relative velocity along the line of sight is determined. In order to control the spacecraft, however, the real speed is needed in the room. So far, the movement of the probe against the sky background was observed to several days. In principle, the measured signal from the radio of the quasar time difference (the delta subtracted) from the time difference between the spacecraft. The position can be accurately determined with the delta-DOR method, since the error in the measurement of the spacecraft position can be corrected by the similar error in the Quasarposition.
This procedure was applied in the NASA space probe Phoenix and the two Mars Exploration Rovers and the ESA probe Venus Express and Rosetta for use. [1] [2] [3] [4]

member_28108 · Post by **member_28108** » 05 Dec 2013 07:25

http://www.esa.int/Our_Activities/Opera ... _delta_DOR

member_28108 · Post by **member_28108** » 05 Dec 2013 07:56

There is the relative speed and actual speed which are different and that accounts for the discrepancy. For eg right now the relative speed is 11584 Kms/hour whereas the speed+rate = 118207Kms/hour.(Data from NASA Eyes) It depends on the frame of reference. ie currently the "real rate" is around 32.8 kilometers /second in reference to the sun.

shyamoo · Post by **shyamoo** » 05 Dec 2013 21:58

prasannasimha wrote: My son is in 12 the standard. He was in 9 the standard when he won it (if I remember right) . He also won the ISRO quiz and science aptitude contest for 3 years in a row. The rover competition was a team event. 3 a team. There was a defined obstacle course shown to them at the starting. Only self developed mechanical sensors were allowed. They had to course correct avoiding side walls and obstacles. Finally hit an end wall and throw a weight. They were scored on time traversed, weight and greatest throw of the given weight. Only 3 teams reached the final wall and my sons team was the first, threw it farthest and was the lightest. He also was given a personal interview with TK Alex! They particularly liked one contact sensor and a part of the transmission and it actually beat the reference model built by ISRO ! This really excited both the team and the ISRO scientists ! One of them phoned me to get permission for the interview with TK Alex and he was very happy.
Coming back to the camera discussion - the points for weight budgeting was very high and they had to account for every gram as this was considered a part of the payload - this was emphasized by the ISRO Scientists there when they were explaining how the assessment would be made.

Impressive!! RESPECT saar.

So, is this space stuff just a hobby for your son or does he plan to make a career out of it? I'm pretty sure he will have an inside track into ISRO if he so chooses. Just a guess. No clue about the whole process of getting into ISRO.

member_28108 · Post by **member_28108** » 05 Dec 2013 22:47

You know children especially teenagers - change their liking's every other day.Currently his craze is mechanical engineering.He will be taking engineering entrances and ISRO space institute entrance. Let us see how his luck plays out.We are all doctors at home but he has an aptitude for engineering (after Mama and Papa his next word was light and switch and it was hell keeping a crawling baby from electrocuting himself !! I believe that if he wants to go to ISRO he may get a priority because of his wins but that has to be seen (He wants to join either ISRO or DRDO but children change their liking's every other day so again - let us see) One thing is that those competitions were done to enthuse children to take up space research as a careerand identify talent and try to make them take up future jobs in ISRO.

Indranil · Post by **Indranil** » 06 Dec 2013 00:29

I am sorry. I have to play the bad guy here.

I am proud of the teen's accomplishments and wish him the best in life, but please don't discuss a particular child here. It is terribly off topic. I hope Simha sir and others would understand.

Varoon Shekhar · Post by **Varoon Shekhar** » 06 Dec 2013 03:37

A major posting on the ISRO facebook page, feels pretty certain that the LAM of the satellite will not be firing anymore. The MTT( Mars transfer trajectory) operation was the last ignition of that engine. From now on, according to the post, the thrusters will be used for any orbit correction or insertion. Is the poster correct, or just speculating?

disha · Post by **disha** » 06 Dec 2013 04:28

Part correct.

[and quoting following from memory, will recheck and correct later]

To ensure the "thrusters etc" will be working after 300 days., the current LAM will be "shutdown - that is not firing anymore, valves on its fuel lines closed etc" and new valves and fuel lines will be opened up.

So yes, the current LAM of the satellite will not be firing anymore. What will be firing will be something else and this is per design (and during orbit insertion only)

Indranil · Post by **Indranil** » 06 Dec 2013 04:40

LAM will not be used for the Trajectory Control Maneuvers(I am sure of this). But if, my memory is serving me right, LAM will be used for the Mars orbit injection (Not so sure of this).

member_28108 · Post by **member_28108** » 06 Dec 2013 08:25

LAN will refire (using a different fuel/oxidiser patheway) after 300 days for orbital reinsertion.

member_28108 · Post by **member_28108** » 06 Dec 2013 08:28

indranilroy wrote:I am sorry. I have to play the bad guy here.

I am proud of the teen's accomplishments and wish him the best in life, but please don't discuss a particular child here. It is terribly off topic. I hope Simha sir and others would understand.

No issues. The only reason I really replied was because it shows the efforts being made by ISRO to fire up the minds of the young and to attempts to ensure future scientists for ISRO.

Victor · Post by **Victor** » 06 Dec 2013 10:13

Plans are for 4 trajectory corrections using its 22N attitude thrusters, the first on December 11th, and then finally the 440N LAM when it gets to Mars.

From spaceflight101:

Arriving at Mars, Mangalyaan fires its Liquid Apogee Motor in order to insert itself into an elliptical orbit around Mars. The MOI Maneuver is the biggest nail-biter of the mission as the Liquid Apogee Motor has to function properly even after spending months in cruise mode to Mars.

Although LAM has flown on various GEO satellites and the Chandrayaan-1 Moon Probe, the engine has never had such a long break in between duty cycles performed in space. Should the MOI Burn not start on time or achieve the required change in velocity, Mangalyaan would be lost in its orbit around the sun.

Lalmohan · Post by **Lalmohan** » 06 Dec 2013 12:44

given the time lag for radio signals to arrive from mars, i would expect the mangalayaan to fire the LAM to enter orbit autonomously. that implies that it by itself must have a very good idea of where it is in order to do so. conceptually a simple problem, but fraught with many many practical difficulties

member_28108 · Post by **member_28108** » 06 Dec 2013 12:49

It has to do it by design in autonomous mode. Usually the updates in position are fed a few hours before. For eg they had fed the data for the last firing 16 hours before and had an unexpected automated period when they list contact for 4 minutes and the space craft performed as expected. With a 23 minute one way delay automation and self rectification is mandatory for the craft and :so integral for any deep space mission with sufficient time lag for signal transmission

Abhaey · Post by **Abhaey** » 06 Dec 2013 12:54

VikramS wrote:
Abhaey wrote:My latest article may be of interest to you:

Mars is a 'Red' Herring: Why India's Space Programme Is a Global Role Model
Oh I did not know you are here on BR ; saw you on HuffPo and Twitter.

I hope you enjoyed reading the articles

Lalmohan · Post by **Lalmohan** » 06 Dec 2013 13:08

prasannasimha wrote:It has to do it by design in autonomous mode. Usually the updates in position are fed a few hours before. For eg they had fed the data for the last firing 16 hours before and had an unexpected automated period when they list contact for 4 minutes and the space craft performed as expected. With a 23 minute one way delay automation and self rectification is mandatory for the craft and :so integral for any deep space mission with sufficient time lag for signal transmission

hence my interest in star trackers...

member_28108 · Post by **member_28108** » 06 Dec 2013 18:34

http://en.wikipedia.org/wiki/Attitude_control

http://www.ae.iitm.ac.in/~amitk/AS3010/ ... ensors.pdf

Varoon Shekhar · Post by **Varoon Shekhar** » 07 Dec 2013 19:10

Can anyone point to a website which tells us how far Mangalyaan/MOM is at any time? We know that it crossed 925,000 km a few days ago. Obviously, since then, it has gone even farther. But how much farther? Has it crossed 1 million, 1.5 million, 2 million etc? Or will they announce these distances as they occur? A layman doesn't know the distance and speed these satellites travel in deep space!