1. PSLV C 25 rocket.
2. 24 September 2014, MOM entered the Aero-centric orbit of Mars.
The control of MOM is done from
the Satellite Control Center (SCC) at Peenya in Bangalore once they are in
the proper orbits. The telemetry data is received and processed here by
scientists. Adjustment of positions and manoeuvres of spacecrafts
(including geostationary satellites also) is done from here.
SCC is part of the master
control facility MCF of ISRO (Indian Space Research Organization) at HASSAN in
Karnataka. Project and mission heads take decisions from here.
The Earth station to receive
all the telecommunication signals is at a different geographical site, where
huge antennas are built in a noise-free remote area.
See the diagram which show
the first two phases. The other diagram shows MOM.
MOM was launched from Surface of Earth on
5th November 2013, in the first phase called Geo-centric phase. The launch was done from Satish Dhawan Space
center at Sri Hari Kota in Andhra Pradesh. It was in this phase for 25 days. PSLV XL-C25 rocket carried MOM into space at
the launch. In this duration MOM travelled 192,800 km from Earth’s centre. There some technical problems in putting MOM
in 2nd phase and making MOM escape from Earth’s gravitational
field. The escape velocity was not
reached properly in expected manoeuvres.
PSLV does not have capability to launch MOM
directly into the trans-mars orbit. So
Apogee of MOM around Earth raised a lot and then induced in to trans-Mars
orbit. During this phase the control of
the space craft control center at ISRO, Peenya, Bangalore.
MOM was introduced into a trans-Mars orbit on
30th November 2013, in the second phase called Helio-Centric Phase. It took a 23-minute long engine firing to
escape from Earth. In this phase MOM
travelled 780 million kilometres around Sun to reach the intended orbit around
Mars. During 10 month travel of MOM,
some manoeuvres (test firing) are done to correct its orbit and path. During this phase the communication was
shifted from low gain antenna to a medium gain antenna, as the distance
MOM started orbiting in the
specified orbit around Mars on 24th September 2014. That is the 3rd phase of
MOM called Areo-Centric phase. Now MOM
is sending signals corresponding to images of Mars and its atmosphere. In this orbit, MOM goes in an elliptical
orbit around Mars with a periapsis of 421 km (nearest distance from Mars) and
with an apoapsis of 77, 000 km (farthest distance from Mars).
payloads means making the
payloads and MOM suitable to withstand all conditions that will be present in
its orbit and any other possible events that may be encountered.
Atmospheric conditions, dust, radiation from every where & light
from Sun, temperature ranges, and possible eclipses. Strengths and
characteristics of materials used should be suitable to these.
Further the capabilities of
the electronic instruments and imaging apparatus are designed to be able to
sense or capture the data from the atmosphere and the shallow surface of Mars.
See diagram of MOM please.
The 2nd diagram shows the payloads clearly.
Payloads on Mars Orbiter
MOM has 5
scientific exploration based instruments or devices. These are the
payloads (electronic devices). Lyman-Alpha Photometer (LAP),
Methane sensor(MSM), Exospheric Neutral composition Analyzer (MENCA), Thermal
Infrared Imaging Spectrometer(TIS), Mars Color camera (MCC). See diagram for their accommodation. These are functioning
now and are sending data to us through the transponder device. These
are weighing 1 kg to 3 kg each.
MOM weighs 1350 kg
along with its fuel. It has solar panels to generate 800 Watts of energy
and is stored in a Lithium ion battery. MOM has fuel to last
for 1 year as against 6 months intended mission (when it entered the
Aero-centric orbit). There
are three antennas high gain antenna, medium gain antenna and low
gain antenna. There
is a reflector that receives signals and transmits signals towards Earth.
A transponder communicates with master control facility of ISRO, via a TWT
amplifier and an antenna array.
Aluminum and CFRP (Carbon
Fiber Reinforced Polymer) material is used for MOM as it has high strength/unit
mass, no rusting, and high temperature withstanding capability.