Mangalyaan : ISRO's Mars Orbiter Mission

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby shiv » 15 Aug 2015 10:03

prashanth wrote:http://www.isro.gov.in/sites/default/fi ... 02.mp4.mp4

http://www.isro.gov.in/pslv-c25-mars-or ... era-images

Nice visualization of a canyon 4000 Km long, 200 Km wide and 7 km deep. Imagine the size of the river that created it.
Its amusing they have used a Hollywood movie theme for background audio.


:x :x :x Where's the "Like" button???


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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SaiK » 17 Aug 2015 20:42

nice visualization.. question:

the rendering does project the canyon max height -> not height, but top is the mars surface. is that true that this is more like an erosion than a formation from a volcanic spew or asteroid strike?

or it could be visualization software limitation to chop at the surface and focus only on the depth.


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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SaiK » 17 Aug 2015 22:09

peachy! thanks.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby JE Menon » 18 Aug 2015 20:43

Thank you for posting that Prashanth. Set to the most appropriate music, brought tears to my eyes. I've forwarded it to a Dutch friend, pointing out that the first crater hovered over is Oudemans (named after the Dutch astronomer Jean Abraham Chretien Oudemans). Of course, my friend will also then realise that it is an Indian spacecraft that took the photographs that permitted the 3D rendering. Some little soft power projection never hurts.

I look forward to a day, in my lifetime hopefully, when we have 101 nuclear/solar powered drones on permanent Martian surface monitoring duty.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SaiK » 19 Aug 2015 03:01

JEM saab perhaps we/you have some martian genes left!.. [the same or similar music discovery channel plays when elephants touches their dead kith & kin's bones] NASA is heavily thinking about deployments. It is going be horrendously hard to live out there.. At first any communication to reach Earth would be like 30 minutes perhaps... so, our brains need to cope up with this time lapse to talking to Earthians.

Heck.. I think also thinking seriously on one-way travel to death. If NASA calls, and none to stop me.. I get a chance to create history. But then, who knows when the call would be?

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SaiK » 21 Aug 2015 02:26


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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Neela » 21 Aug 2015 14:38

Summary of a German Radio' programme today:
- 300 million living in poverty yet a spectacular Mangalyaan mission.
- some excerpts from interviews with Annadurai
---- Space program used for fisheries, farming , tele-education
---- One particular comment/joke that stood out: "On Facebook, students were calculating velocity of Mangalyaan...hey thats out job. But yes we are happy that this has inspired kids"
- Second mission is being planned.
- Planned Launch end/Aug will augment connectivity to rural areas. The govt intends to provide connetivity to all and is dead serious about it.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Varoon Shekhar » 21 Aug 2015 18:31

One of the criticisms some people made was that the instruments on board Mangalyaan were too small and feeble,to really show anything or discover anything. It's safe now to say that these fears were unfounded, the images have been praised worldwide as being of high quality.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby member_28108 » 21 Aug 2015 19:55

Varoon Shekhar wrote:One of the criticisms some people made was that the instruments on board Mangalyaan were too small and feeble,to really show anything or discover anything. It's safe now to say that these fears were unfounded, the images have been praised worldwide as being of high quality.


Yes I remember people in the highest echelons also taking issues with it including people who formerly worked in ISRO but it is indeed a tribute to people in ISRO and the payload selection team headed by Dr UR Rao who persisted and gutsy enough to send this probe. If we had waited to get our cryogenic engine up and about we would have missed this Mars "launch window" and missed a great opportunity. As they say "opportunity knocks to those who dare'.


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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Amber G. » 28 Sep 2015 18:27

Nasa is going to have a major announcement.. Lot of excitement.. liquid water on Mars?
(So Chandrayaan finds water on Moon .. and remember I posted a year ago about hoping Mangalyaan will discover similar big thing..:)

NASA@Nasa wrote:Mars mystery solved? Find out Monday at 11:30am ET at a live briefing on NASA TV: http://go.nasa.gov/1iR2VZU Q? #askNASA


It will not be going out on a limb and say that NASA is going to announce that a source of free-flowing water has been discovered on Mars' surface.

This could forever change how we view Mars, Because it means that we can use this liquid water for irrigation, drinking and even for fuel.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Amber G. » 28 Sep 2015 20:14

^^^ The press conference is going on now... Yes the announcement is about flowing water...it is also the news item in major news media..

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby deejay » 28 Sep 2015 20:23

^^^ Thank You Amber G. for the focus on the news.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Comer » 28 Sep 2015 21:32

Amber G, due to the temperature ( and possibily to the salt) what exactly is the state it is in? IIRC there are multiple stages in water state.
Also, is Mars geologically active?

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby member_28108 » 28 Sep 2015 22:25

It is not ordinary liquid water but a salt - briney fluid of perchlorate.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Amber G. » 29 Sep 2015 01:30

prasannasimha wrote:It is not ordinary liquid water but a salt - briney fluid of perchlorate.

Yes, perchlorate (the best mineral matches to the spectral data -- magnesium perchlorate, magnesium chlorate, and sodium perchlorate) were discovered quite some time ago (spectrum) in polar regien, but relatively new find is that they exist in equatorial reasons too...

They were talking about the existence of briny water which may explain a phenomenon observed by Mars orbiters called "recurring slope lineae," (LSL) ( dark streaks on slopes that appear and grow during the planet's warm season).

Just like salt water on earth which freezes at lower than 0C..These briny water becomes in liquid form if temperature is above (-23C)....briny puddles meters long etc,,(The presence of perchlorate salts could lower the melting temperature of water at Martian conditions by 40C making it much easier for water to melt.)

For details see, for example https://storify.com/lmorello/water-on-mars

Let me end this by something I wrote almost exactly a year ago: :) Time is NOW to name some of these LSL's after ghat's (Like "asi- ghat")

quoting my own post from this dhaga almost a year ago..
Amber G. wrote:I think it will be cool to have a story about mangalyaan and Ganges Chasma .

Ganges Chasma as you may or may not know is an ancient river bed type object on Mars.


If you look at map of the mars, look at 8.0°S and 48.1°W

( It is named after the River Ganga and is thought to have formed through a series of catastrophic discharges of water in ancient times.

Considering the inclination of MOM's orbit of 150, this feature will be available to be photographed..

Here is a picture of the feature.
Image..

Or please look at the article, for example:
http://themis.asu.edu/feature/1
***
Let us make a push so some of the features along this chasma are named after some famous ghats
along Ganga river. (isro should be able to do this)
***
(I predict here that few days from now, there will be stories, how NaMo, who won from a city on the bank of Ganga -- planned all that :) )

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Comer » 29 Sep 2015 19:32

Thanks prasannasimha and Amber G.
So the best guess of where the water comes from is atmosphere? And if so, would there be a water cycle as well? Because RSLs are found not necessarily only near polcar caps.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Amber G. » 01 Oct 2015 19:38

One more thing.. looks like these Outcrops in Ganges Chasma in Mars ..(see picture below)

Image

(From Link: Rockslides and Outcrops in Ganges Chasma


Looks like it is supporting digital India's campaign of Face book. (look at orange and green - transparent hues and network of lines..
Image

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Bade » 12 Oct 2015 05:13

There is a whole special section on MOM in Current Science.

25 September 2015, 109 (06)

Category : Special Section: Mars Orbiter Mission

Preface | 25 September 2015, 109 (06) DjVu | PDF
Seetha, S.; Satheesh, S. K.
Foreword | 25 September 2015, 109 (06) DjVu | PDF
Kiran Kumar, A. S.
Concept design and planning of India’s first interplanetary mission | 25 September 2015, 109 (06) DjVu | PDF
Adimurthy, V.
PSLV-C25: the vehicle that launched the Indian Mars Orbiter | 25 September 2015, 109 (06) DjVu | PDF
Vishnu Nampoothiri, M.; Sowmianarayanan, L.; Jayakumar, B.; Kunhikrishnan, P.
Mars Orbiter Mission spacecraft and its challenges | 25 September 2015, 109 (06) DjVu | PDF
Arunan, S.; Satish, R.
Mission automation and autonomy for the Mars Orbiter Mission | 25 September 2015, 109 (06) DjVu | PDF
Karidhal, Ritu; Harinath, Nandini; Robert, P.; Kesavaraju, V.
Mars Colour Camera: the payload characterization/calibration and data analysis from Earth imaging phase | 25 September 2015, 109 (06) DjVu | PDF
Arya, A. S.; Sarkar, S. S.; Srinivas, A. R.; Manthira Moorthi, S.; Patel, Vishnukumar D.; Singh, Rimjhim B.; Rajasekhar, R. P.; Roy, Sampa; Misra, Indranil; Paul, Sukamal Kr.; Shah, Dhrupesh; Patel, Kamlesh; Gambhir, Rajdeep K.; Rao, U. S. H.; Patel, Amul; Desai, Jalshri; Dev, Rahul; Prashar, Ajay K.; Rambhia, Hiren; Parnami, Ranjan; Seth, Harish; Murali, K. R.; Kaushik, Rishi; Patidar, Deepak; Soni, Nilesh; Chauhan, Prakash; Samudraiah, D. R. M.; Kiran Kumar, A. S.
Methane Sensor for Mars | 25 September 2015, 109 (06) DjVu | PDF
Mathew, Kurian; Sarkar, S. S.; Srinivas, A. R.; Dutta, Moumita; Rohit, Minal; Seth, Harish; Kumaran, Rajiv; Pandya, Kshitij; Kumar, Ankush; Sharma, Jitendra; Desai, Jalshri; Patel, Amul; Patel, Vishnu; Shukla, Piyush; Manthira Moorthi, S.; Singh, Aravind K.; Gupta, Ashutosh; Rathi, Jaya; Narayana Babu, P.; Kuriakose, Saji A.; Samudraiah, D. R. M.; Kiran Kumar, A. S.
Thermal Infrared Imaging Spectrometer for Mars Orbiter Mission | 25 September 2015, 109 (06) DjVu | PDF
Singh, R. P.; Sarkar, Somya S.; Kumar, Manoj; Saxena, Anish; Rao, U. S. H.; Bhardwaj, Arun; Desai, Jalshri; Sharma, Jitendra; Patel, Amul; Shinde, Yogesh; Arora, Hemant; Srinivas, A. R.; Rathi, Jaya; Patel, Hitesh; Sarkar, Meenakshi; Gajaria, Arpita; Manthira Moorthi, S.; Pandya, Mehul R.; Gujrati, Ashwin; Chauhan, Prakash; Kuriakose, Saji A.; Samudraiah, D. R. M.; Kiran Kumar, A. S.
MENCA experiment aboard India’s Mars Orbiter Mission | 25 September 2015, 109 (06) DjVu | PDF
Bhardwaj, Anil; Mohankumar, S. V.; Pratim Das, Tirtha; Pradeepkumar, P.; Sreelatha, P.; Sundar, B.; Nandi, Amarnath; Vajja, Dinakar Prasad; Dhanya, M. B.; Naik, Neha; Supriya, G.; Satheesh Thampi, R.; Padma Padmanabhan, G.; Yadav, Vipin K.; Aliyas, A. V.
Lyman Alpha Photometer: a far-ultraviolet sensor for the study of hydrogen isotope ratio in the Martian exosphere | 25 September 2015, 109 (06) DjVu | PDF
Sridhar, Raja V. L. N.; Rao, M. V. H.; Kalyani, K.; Bhaskar, K. V. S.; Chandran, Anand; Mahajan, Monika; Bhaskar Manja, A.; Gouda, Girish M.; Tayaramma, J. D. P. V.; Amudha, P. R.; Kandpal, Madan Mohan; Pramod, K. B.; Viswanath, S. G.; Prasad, L. V.; Laxmiprasad, L. S.; Chakraborty, P.; Kamalakar, J. A.; Nagendra Rao, G.; Viswanathan, M.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby member_28108 » 12 Oct 2015 10:27

Nice set of articles

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby member_28108 » 12 Oct 2015 11:59

SSSalvi,
data colection seems to occur both at apoaerion and periaerion

As per the articles from the PDF links above
During periareion imaging, all the three instruments are
nadir-pointing. TIS, MSM and MCC acquire data only
when the scene is illuminated.
The data will be acquired
in push-broom mode for MSM and TIS. MCC always
operates in frame mode in both the apoareion and
periareion regions.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SaiK » 09 Sep 2016 01:14

any update after this lakdiwala report?
http://www.planetary.org/blogs/emily-la ... pdate.html

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Amber G. » 17 Sep 2016 09:16

Seems like only yesterday - The very first picture taken by MCC ---
First image of the Earth by MCC (Mars Color Camera) of ISRO's Mars Orbiter Spacecraft taken on Nov 19, 2013.

Image

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Varoon Shekhar » 24 Sep 2016 07:11

In case it missed people's attention, Sept 24th( India time) marks 2 years since Mangalyaan reached its Martian orbit, on Sept 24th/2014. It was originally expected to last 6 months. A round of applause is in order! I'm sure ISRO is aware of the 2 year length.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby navneeet » 25 Sep 2016 18:46

The Mars Atlas by ISRO

http://www.isro.gov.in/sites/default/files/article-files/pslv-c25-mars-orbiter-mission/celebrating-one-year-of-mars-orbiter-mission-orbit-release-of-mars/Mars-atlas-MOM.pdf

The press release

http://www.isro.gov.in/sites/default/files/article-files/node/5223/isro-lta_release_mom_browser.pdf

Mars Orbiter Mission Long Term Archive Release Statement

Mars Orbit Insertion on 24th Sep 2014

After a 300 days journey in deep space, on September 24, 2014, India's Mars Orbiter Spacecraft successfully entered into an elliptical orbit around planet Mars by firing its 440 Newton Liquid Apogee Motor along with eight smaller liquid engines.
•With successful Mars Orbit Insertion, ISRO became the fourth space agency to successfully send a spacecraft to Mars orbit and India became the first country in the world to do so in its first attempt.

May 27, 2015 to July 01, 2015; MOM was behind the Sun as viewed from the Earth and no communication was possible between MOM and Earth. Spacecraft survived in full autonomy mode for a period of 35 days.

Mars Orbiter mission experienced a white out geometry between 18th May to 30th May 2016. MOM is built with full autonomy to take care of itself for such a long period. No commanding was carried out on the satellite during the white out period. Payload operations were suspended. The spacecraft came out of White out geometry successfully on the 30th May 2016 and has been normalized for regular operations.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Varoon Shekhar » 25 Sep 2016 22:05

http://www.thehindu.com/sci-tech/scienc ... s#comments

The Mars Orbiter that catapulted India to space history has quietly had its second birthday - in its orbit around Mars.

On September 24, 2014, India became the only nation to date to put a spacecraft around the red planet in its very first attempt.

The debut achievement of making the spacecraft go round the planet was the most challenging manouevre of the mission. It eluded old planetary warhorses Russia, the U.S. and Europe, who started out into space 50 years back with superior rockets.

Originally designed to last just six months on its onboard fuel, the orbiter continues to scan the red planet elliptically from a distance of around 400 km x 70,000 km.

Indian Space Research Organisation (ISRO) said it still sends interesting photos and information to Indian data keepers across millions of kilometres.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SaiK » 08 Oct 2016 21:33

http://www.isro.gov.in/pslv-c25-mars-or ... m-released

can someone get more more deep-dive info from here?

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SSSalvi » 08 Oct 2016 22:08


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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SaiK » 13 Oct 2016 18:27

here is one more
http://aviationweek.com/space/imagery-i ... es-1524291


Image
Image
Image
Image
Image
Image

http://aviationweek.com/space/indias-cl ... es-1405701
Image
Image
Image
Image
Image


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

now, we need to get the high res versions from ISRO

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Varoon Shekhar » 01 Nov 2016 00:26

Prasannasimha, I address my query to you :-). Did Mangalyaan travel 670 million km in its long journey, or 780 million km?

Also, is Mangalyaan's orbit novel, i.e essentially equatorial, as opposed to polar. I read somewhere, if I didn't misunderstand, that MOM's orbit is the first one to go around the equator. All the other spacecraft went around the poles. Is this correct. If so, it makes MOM that much more impressive, and it's already that!

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SSSalvi » 01 Nov 2016 17:20

^^^
Sorry for Jumping the queue ;) .

I don't know which distances you are referring to.

From 1st Dec ( when MOM went out of Earth's orbit, it travelled slightly less than 700 Million kms to reach Mars.

Image

What you are referring to other distance could be the travel from Launch ( 5th Nov 2013 ) to 1st Dec 2013 ( Horizontal portion at the beginning in right part of next figure which works out to about 80 Million kms ( about 630 Hours * 107000 Kms/hr Earth speed.) added to the above number.
Image

====

Mangalyaan orbit is Neither Polar nor Equatorial .. It has inclination of 150 deg ( i.e. the orbit makes 30 deg w.r.t Martian Equator.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Varoon Shekhar » 01 Nov 2016 20:33

Thanks SSSalvi! I see.So the "extra" 80 million km is accounted for by the distance before the TMI or trans Martian injection?

I do remember reading somewhere, that Mangalyaan's orbit was a 'first of its kind'. Perhaps we could call it non-polar, since all the other Mars spacecraft were in polar orbits around the planet. MOM is the first in a non-polar( though not strictly equatorial) orbit. Is that more accurate?

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SSSalvi » 01 Nov 2016 23:17

MOM is the only craft to image from 400 Kms to 80000 Kms covering high resolution when near and Full disk when away from Mars.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Amber G. » 01 Nov 2016 23:54

Varoon Shekhar wrote:Prasannasimha, I address my query to you :-). Did Mangalyaan travel 670 million km in its long journey, or 780 million km?

Also, is Mangalyaan's orbit novel, i.e essentially equatorial, as opposed to polar. I read somewhere, if I didn't misunderstand, that MOM's orbit is the first one to go around the equator. All the other spacecraft went around the poles. Is this correct. If so, it makes MOM that much more impressive, and it's already that!

Assuming normal scenario, (Hoemann Transfer Orbit) *ALL* spacecrafts from earth to Mars travels about the same distance. This, of course, assumes, not counting orbits around earth or Mars - IOW after the initial thrusters (and before final braking thrusters) and the total path is seen with respect to Sun.

This is fairly simple. . The distance of Mars from sun is about 1.5 AU, (AU= 150 Million KM). so average is 1.25 AU, multiply this by 3.14 and you get 600 million Km.
(The ellipse part of transfer orbit makes a some difference but not much, after all even for this transfer orbit were perigee is earth and apogee is Mars, e comes out to be only about 0.2. IOW e = (1.5-1)/(1.5+1), and doing more accurate math does not make a difference of more than a few percentage.

Hope this helps.
(Each orbit adjustment will add some to this 600 million miles, each extra orbit will too. This long journey is, of course, with respect to sun - if you take earth as frame of reference, calculation becomes a little complicated but IMO that part is not important )

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SSSalvi » 02 Nov 2016 10:17

^^^
@ Varoon
Can you give link(s) where the 670 and 780 millions are mentioned?

@ Amber G

600 Million is half orbit distance that Mars travels around Sun ( 2*pi*r = circumference ), not the Earth to Mars travel distance along Hoemann Txr.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Varoon Shekhar » 02 Nov 2016 19:05

http://phys.org/news/2013-12-indian-cra ... -mars.html - mentions 780 million


http://www.atimes.com/atimes/South_Asia ... 60914.html says 670 million

There are many such references, including from IBN, NDTV, Frontline et al.

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby SSSalvi » 02 Nov 2016 19:44

^^^
1st reference seems to have confused the dist with US probe MAVEN which traveled over 700 million Kms. ( 712 Million Kms to be exact )

The paths of 2 probes can be seen in the figure my earlier post,

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Re: Mangalyaan : ISRO's Mars Orbiter Mission

Postby Amber G. » 02 Nov 2016 20:57

SSSalvi wrote:^^^
@ Amber G

600 Million is half orbit distance that Mars travels around Sun ( 2*pi*r = circumference ), not the Earth to Mars travel distance along Hoemann Txr.


@SSSalvi,
600 Million miles is essentially (within few percentage) the path along Hoemann orbit. (Not of Mars half orbit but average of Mars and Earth's half orbits).

That, is for an elliptical orbit whose perigee is at 1 AU (Earth/Sun distance) and apogee is at 1.5 AU. If you use calculus/computer the elliptical path comes out to be about 3.89 AU and my approximation (pi*1.25) is 3.93 AU. Within 1%. (That is about 600 Million Km). This is the distance covered (wrt sun) while *no* burn is taking place. (IOW after the burn near Earth, and before the burn near Mars - neglecting in course corrections)

Of course, there are a few additional factors:

1. The actual orbit may differ from ideal Hoemann. (Not uncommon in many cases least energy orbit may be different - sometimes, for example for outer planets sling shot was done by going up to Venus etc)

2. I am not sure what exactly they mean by "distance covered".. is this wrt to Sun or with respect to Earth?

Hope this is clearer.
***

For those who want to do simple calculation without computers (yet want to get accurate answers) few simple geometric points may help tremendously ..

For elliptical orbit, if perigee = p and apogee is = q
The semi-major axis =a = (p+q)/2 (Arithmetic Mean)
The semi-minor axis = b = sqrt(pq) (Geometric Mean)
The latus rectum (to calculate angular momentum) = l = Harmonic Mean ( = 2pq/(p+q))

The e= (p-q)/(p+q)

This will help visualize/calculate etc virtually all you want to know about the orbit shape.

The time period (=T), (and total energy (=E) of orbit) depends *only* on semi-major axis (=a).
The angular momentum can be calculated from l (latus).


This is *all* you need to calculate most of the parameters. You also need value of "GM" (G= gravitational constant and M= Mass of central body -- earth for satallites, Sun for planet probes) let us call this value K

If you don't remember any of the formula's, just remember circular orbit(s) from elementary physics. substitute "a" instead of "r" to calculate energy/time-period etc, and substitute "l" instead of "r" for angular momentum.

Now Time period of the orbit use the formula == (angular velocity = w = T/2*pi) = sqrt (a^3/K)
Velocity at any distance "r" can be given by conservation of Energy, and PE is simply = -K/r
and total energy (which is negative for elliptical/circular orbits) = -K/2a
so (1/2) v^2 = K(1/r-1/2a) .... (So you can calculate the velocity of mangalyaan at *any* point at a given distance from sun easily -- and it is *very* accurate).

This (and high-school geometry) is *all* you need to calculate, orbit parameters; velocity at any given point etc

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My quote from previous post above, I wrote:Assuming normal scenario, (Hoemann Transfer Orbit) *ALL* spacecrafts from earth to Mars travels about the same distance. This, of course, assumes, not counting orbits around earth or Mars - IOW after the initial thrusters (and before final braking thrusters) and the total path is seen with respect to Sun.

This is fairly simple. . The distance of Mars from sun is about 1.5 AU, (AU= 150 Million KM). so average is 1.25 AU, multiply this by 3.14 and you get 600 million Km.
(The ellipse part of transfer orbit makes a some difference but not much, after all even for this transfer orbit were perigee is earth and apogee is Mars, e comes out to be only about 0.2. IOW e = (1.5-1)/(1.5+1), and doing more accurate math does not make a difference of more than a few percentage.

Hope this helps.
(Each orbit adjustment will add some to this 600 million miles, each extra orbit will too. This long journey is, of course, with respect to sun - if you take earth as frame of reference, calculation becomes a little complicated but IMO that part is not important )


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Added Later:
Varoon, @SSS and others - It will be interesting to know how (what basis - is it wrt to earth or sun etc) the total distance is being calculated in those articles.

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To be honest, for me, that *very precise* figure is not really that scientifically relevant unless the context is defined.

Just think about it, Mangalyaan, (or the writer of this post :) for that matter) "travels" more than 2.5 million Kms every day (wrt to sun) even if it was just sitting on earth and doing nothing more than lurking in brf.
Last edited by Amber G. on 03 Nov 2016 00:35, edited 1 time in total.


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