Quote from: vyoma on 10/02/2014 02:40 pmThere was a discussion about PAM-G, cryogenic engine restart capability and how Centaur upper stage does it, in one of the GSLV discussion threads. You may find it interesting:http://forum.nasaspaceflight.com/index.php?topic=33622.msg1148624#msg1148624Thanks vyoma! I vaguely remember reading these posts sometime back, but then later forgot the forum. Its quite informative. Quote from: antriksh on 10/02/2014 02:49 pmEven if we use PAM-G, payload and mission life would be much more than what can be achieved using PSLV.Ok.. So the Mars payloads you quoted in one of your earlier posts (1000kg for elliptical and 550kg for circular orbits), are they applicable when using PAM-G? What are the other solutions ISRO can consider for Mars missions using GSLV-II (barring, of course, the restartable cryo-stage) ?
There was a discussion about PAM-G, cryogenic engine restart capability and how Centaur upper stage does it, in one of the GSLV discussion threads. You may find it interesting:http://forum.nasaspaceflight.com/index.php?topic=33622.msg1148624#msg1148624
Even if we use PAM-G, payload and mission life would be much more than what can be achieved using PSLV.
The Mars Orbiter Mission (MOM) has a methane sensor, based on Fabry-Perot etalon, which can measure the CH4 at several ppb levels (Goswami et al, 2013). Detailed measurements of methane levels in the atmosphere over long periods from an orbiting platform would definitely answer some of the pertinent questions regarding the Martian methane.
New image showing the Elysium
Quote from: vineethgk on 10/02/2014 04:40 pmOk.. So the Mars payloads you quoted in one of your earlier posts (1000kg for elliptical and 550kg for circular orbits), are they applicable when using PAM-G? What are the other solutions ISRO can consider for Mars missions using GSLV-II (barring, of course, the restartable cryo-stage) ? Indian Space Policy wise, you can spin the first mission of every kind as a technology demonstrator, but the next one is going to have to be a service carrying some foreign science payload. I think most other agencies are maxed out on their Mars budgets right about now. So... I'd rather the second Mangalyaan... if there is indeed going to be one in 2018 - be our first foray into ion-engines (on the Earth end), and aero-braking (at Mars).
Ok.. So the Mars payloads you quoted in one of your earlier posts (1000kg for elliptical and 550kg for circular orbits), are they applicable when using PAM-G? What are the other solutions ISRO can consider for Mars missions using GSLV-II (barring, of course, the restartable cryo-stage) ?
While certainly there should be openings for ionternational payloads, what makes you think that idia can't develop useful instruments itself? Indeed, what makes you think that MOM's payload isn't useful now?
To commemorate Indian Space Research Organisation’s (ISRO) Mars Orbiter Mission’s (MOM) grand success and with a view to make coming generation aware about the milestone, Indore Development Authority (IDA) is going to rename an intersection at Super Corridor near Indore Airport as Mars Orbiter Mission (MOM) roundabout."This is for the first time that we are dedicating a crossing to our scientists and the intersection would be renamed "Mars Crossing" or "Mangal Chouraha," he said and added that "The crossing will display a mars shaped ball installed over a red pillar with a message ‘In honour of successful mars mission’ along with details about MOM."
The space agency moved MOM to a "safer position" on Tuesday to avoid any damage to its payloads from the comet's debris. Tuesday's manoeuvre which consumed 1.9 kg of fuel will put the spacecraft at an approximate distance of 1,40,000km from the comet when it flies by. Kumar said MOM was now 400km away from the surface of the Red Planet on the opposite side of the comet.
The spacecraft will carry out observations of the comet and even capture it on its Mars Colour Camera. The duration between the comet's arrival and departure on October 19 will be approximately one-and-a-half hours.
MOM's payload Methane Sensor for Mars will check for presence of Methane on Siding Spring, which is travelling at a velocity of 56km/second relative to the planet
Is it not possible to have attitude control using the reaction control wheels only as long as solar / battery power is available ?
in Earth's orbit you can desaturate reaction wheels using magnetic coils interacting with the Earth's magnetic field as is done on Hubble (which has no propulsion system), but you can't do that in Mars orbit or in deep space.
Quote from: plutogno on 10/10/2014 05:47 pmin Earth's orbit you can desaturate reaction wheels using magnetic coils interacting with the Earth's magnetic field as is done on Hubble (which has no propulsion system), but you can't do that in Mars orbit or in deep space.Why is this not used for all of the Sats. in Earth orbit? and for planets with a magnetic field?Thank you! for the explanation.
Reaction wheels would also incur extra mass penalty and are prone to failures over longer mission durations.
In the second last image, Phobos (encircled) transit over Mars was captured.
ISRO engineers handling MOM from the command centre at Bangalore have been trying to balance MOM’s safety with the visual treat the fly-by promises, according to MOM Mission director V. Kesava Raju. For the October 20 encounter, the 25-plus team of engineers associated with the five MOM instruments were working out the best position for the instruments.
Opportunities to take pictures of the comet and its tail during October 19 – 21 are also under discussion. Post-encounter, the key concern would be to protect MOM’s body from exposure to the large cloud of dust.