National Pride-India Ready to Jump in Mars-Launching Time:2.38 p.m. on Tuesday
India 10.18am 05-11-2013
Mars mission countdown begins
https://plus.google.com/+bhupeshmandalIndia 10.18am 05-11-2013
--:::GOOD LUCK INDIA:::--
--:::WE ARE READY FOR PRIDE:::--
PSLV-C25 to lift off from Sriharikota at 2.38 p.m. on Tuesday
India’s ambitious mission to Mars moved ahead smoothly on Sunday with
the 56.5- hour countdown beginning at 6.08 a.m. at the Sriharikota
spaceport. If the countdown progresses without any “hold,” the
four-stage Polar Satellite Launch Vehicle (PSLV-C25) will lift off from
the first launch pad at 2.38 p.m. on Tuesday (November 5) and put the
1,350-kg Mars Orbiter in a long, elliptical earth-orbit. That will
signal the first step of the spacecraft’s 300-day odyssey to the Red
Planet.
“All is well. The countdown is progressing smoothly. Everything is
fine,” Director of Vikram Sarabhai Space Centre (VSSC) in
Thiruvananthapuram S. Ramakrishnan told The Hindu from Sriharikota around 7 p.m. on Sunday.
“We are relaxed,” said M.Y.S. Prasad, Director of Satish Dhawan Space Centre (SDSC) at Sriharikota.
Both Mr. Ramakrishnan and Dr. Prasad said separately that the filling of
the PSLV-C25’s fourth stage with liquid propellants was completed just
minutes ahead of 7 p.m. on Sunday. The second stage would be filled with
liquid propellants on Monday. The first and third stage were filled
with solid propellants.
K. Radhakrishnan, Chairman of Indian Space Research Organisation (ISRO),
said the cost of the Mars mission was about Rs.460 crores. This
included building the spacecraft and the ground radar stations and
augmenting the capacity of ISRO’s Deep Space Network Station at Byalalu,
near Bangalore.
Criticism
Asked about the criticism that a “poor” country like India is wasting
money on sending a spacecraft to Mars, Dr. Radhakrishnan said, “We want
to tell this country that Mars has a relevance…Science leads to
understanding… Some people ask, “Why are you spending Rs.460 crores?”
Others will say that Rs.460 crores is only some four rupees per head in
this country. Then some others will say it is only the price of an
aircraft. So there are different ways of looking at it…We want to tell
this country that this is a complex mission.”
M. Annadurai, Programme Director of Indian Remote-sensing Satellites and
Small Satellites Systems, ISRO, called the Mars Orbiter Mission “a
logical extension of Chandrayaan-1.” “The mission profile is similar to
that of the moon mission. The powerful PSLV-XL , which put Chandrayaan-1
into orbit, will swing into action in the Mars mission also.
After the Chandrayaan-1 mission in 2008, ISRO chose to head towards Mars
because there are several similarities between the Earth and Mars. They
include solid surfaces, seasons, the duration of their day and the
polar ice caps. Also, if water exists on Mars, there may be microbial
life on the planet.
After India established itself among world leaders in building
application-oriented remote-sensing, communication, weather and
surveillance satellites, which were “our bread and butter missions,” it
was “a natural corollary” that India should turn its attention to
science satellites, ISRO scientists said. Hence Chandrayaan-1, the Mars
mission, Chandrayaan-2 in 2016, Astrosat for study of cosmic sources and
Aditya-1 to study the solar corona.
Suspenseful 43 minutes
Unlike the previous PSLV missions, which lasted about 18 minutes to put
remote sensing satellites into orbit, the flight duration of PSLV-C25
will last a suspenseful 43 minutes before the rocket’s fourth stage puts
the spacecraft into orbit. “This is the speciality of the mission,”
said B. Jayakumar, Vehicle Director. As Mr. Jayakumar and R. Hutton,
Associate Vehicle Director, stood a couple of hundred metres in front of
the Mobile Service Tower encasing the four-stage PSLV-C25 on October
30, they asserted that “the PSLV is a rain-proof vehicle.”
Besides the 43-minute flight, yet another missionspeciality is the
25-minute coasting phase between the third stage burn-outand the fourth
stage ignition. A third speciality is that it is only 37seconds after
the fourth stage burn-out that the spacecraft will be injected into
orbit.
V. Seshagiri Rao, Associate Director, SDSC, said several ground
stations, including two ship-borne radars in the South Pacific Ocean,
would track the vehicle and its positional information would be received
every 100 milliseconds.
Mars Orbiter Mission: Those five minutes are crucial
Mars orbiter spacecraft must be set off between 2.38 p.m. and 2.43 p.m. today
The Mars orbiter spacecraft has just five minutes for getting launched on Tuesday — or it slips into the next day.
It must be set off between 2.38 p.m. and 2.43 p.m.
And the mission has an overall deadline, until November 19, this year. The next best time is not for another 26 months.
“We
are on the threshold of a complex mission. If there is a hold during
automatic launch sequence there then we will not have it on that day. We
can have a maximum of only five minutes. Each day, the launch time
advances by 6-9 minutes. We hope that it will make it [on Tuesday],” K.
Radhakrishnan, chairman, Indian Space Research Organisation (ISRO) told The Hindu recently.
ISRO
scientists, having missed the earlier date of October because a
tracking ship reached its watch post near Fiji late, have their calendar
laid out for each of the remaining days.
“There is
just one opportunity in a day. For each lift-off time, we need to have a
new steering programme ready, a new trajectory design, and all this has
been done,” he said.
“In earlier missions we
worried about only one trajectory and made only a minor change in the
steering programme. This total trajectory design is for each lift-off
time, which is one big challenge for the Polar Satellite Launch Vehicle
(PSLV).”
The flight on the four-stage PSLV-C25 lasts
43 minutes, more than double the time taken for its routine launches
which need about 20 minutes, with a long coasting for the last stage.
Mr.
Radhakrishnan said now they were concentrating on the launch on Tuesday
and then on December 1, when the spacecraft should be put in the
trajectory to Mars. Post-lunch, it will be a series of post-midnight
exercises for scientists tracking the spacecraft from ISRO Telemetry,
Tracking and Command Network (ISTRAC). On Thursday morning, ISTRAC in
Bangalore will start increasing its elliptical orbit in phases by firing
its motors six times.
Dr. Radhakrishnan said the first orbit raising exercise was crucial and would happen on Thursday at 1.15 a.m.
The
remaining orbit expansions would all be done around 2 a.m. on November
8, 9, 11 and 16, until the spacecraft’s apogee (farthest point from
Earth in its elliptical orbit) reaches 1.92 lakh km.
The sixth and last Earth-bound manoeuvre is slated for December 1 at 12.42 a.m.
The
trickiest time will be in September 2014, when the spacecraft will be
near Mars. The scientists have to slow down the spacecraft and bring it
into an elliptical orbit going around Mars.
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