PSLV-C14 Successfully Launches Oceansat-2 Satellite

In its sixteenth flight conducted from Satish Dhawan Space Centre (SDSC) SHAR, Sriharikota today (September 23, 2009), ISRO’s Polar Satellite Launch Vehicle, PSLV-C14 successfully launched the 960 kg Indian remote sensing satellite Oceansat-2 and six nano satellites for international customers into a polar Sun Synchronous Orbit (SSO). This was the fifteenth successful flight of PSLV. PSLV-C14

After a 51 hour count down, PSLV-C14 lifted off from the first launch pad at SDSC SHAR, at 11:51 am IST with the ignition of the core first stage. The important flight events included the separation of the first stage, ignition of the second stage, separation of the payload fairing at about 125 km altitude after the vehicle had cleared the dense atmosphere, second stage separation, third stage ignition, third stage separation, fourth stage ignition and fourth stage cut-off.

The 960 kg main payload, Oceansat-2, was the first satellite to be injected into orbit at 1081 seconds after lift-off at an altitude of 728 km. About 45 seconds later, four of the six nano satellites were separated in sequence. The initial signals indicate normal health of the satellites. Honble Vice President of India Congratulating Madhavan Nair

Oceansat-2 is the sixteenth remote sensing satellite of India. The state-of-the-art Oceansat-2 carries three payloads and has the shape of a cuboid with two solar panels projecting from its sides.

The eight band Ocean Colour Monitor (OCM) payload carried by Oceansat-2 images a swath (strip of land or ocean) of 1420 km width with a resolution of 360 metre and works in the Visible and Near Infrared region of the electromagnetic spectrum. The Ku-band Scatterometer with a 1 metre diameter antenna rotating at 20 rpm, works at a frequency of 13.515 GHz. The Scatterometer covers a swath of 1400 km and operates continuously. ROSA is a GPS Receiver for atmospheric sounding by radio occultation built by Italian Space Agency (ASI).

Soon after separation from PSLV fourth stage, the two solar panels of OCEANSAT-2 were automatically deployed. The satellite’s health is continuously monitored from the ISRO Telemetry, Tracking and Command Networks (ISTRAC) Spacecraft Control Centre at Bangalore with the help of a network of ground stations at Bangalore, Lucknow, Mauritius, Biak in Indonesia and Svalbard and Tromso in Norway as well as a station in Troll, Antarctica.

PSLV-C14 mission carried six nano satellites – Cubesat 1, 2, 3 and 4 as well as Rubin 9.1 and 9.2 – as auxiliary payloads along with Oceansat – 2. The weight of these nano satellites was in 2-8 kg range. Oceansat – 2 and the six auxiliary payloads were placed in a polar Sun Synchronous Orbit inclined at an angle of 98.28 degree to the equator. Pressmeet

The auxiliary payloads of PSLV-C14 are educational satellites from European Universities and are intended to test new technologies. After the separation of Oceansat – 2 from PSLV – C14, the four cubesats were also separated, while Rubin 9.1 and 9.2 remain permanently remain attached to the upper stage of PSLV-C14.

The 44.4 metre (147 ft) tall PSLV – C14 weighed 230 tons at lift-off. PSLV – C14 is the core alone version of PSLV which is the same as PSLV standard configuration except for the strap-on motors. Six such strap-ons surround the first stage of PSLV standard configuration, but are absent in core alone version. PSLV-C14 was the fifth core alone mission of PSLV.

PSLV – C14 had four stages using solid and liquid propulsion systems alternately. The first stage, carrying 139 tonne of propellant, is one of the largest solid propellent boosters in the world. The second stage carried 41.5 tonne of liquid propellant. The third stage used 7.6 tonne of solid propellant and the fourth had a twin engine configuration with 2.5 tonne of liquid propellent.

This was the sixteenth mission of ISROs workhorse launch vehicle PSLV and its fifteenth consecutive success. From October 1994 onwards, PSLV has repeatedly proved its reliability, robust design and versatility by launching satellites into polar Sun Synchronous, Geosynchronous Transfer, Low Earth and Highly Elliptical Orbits. Of the 39 satellites launched by PSLV so far, 17 have been Indian and the rest being satellites from abroad. During many of its missions, including todays PSLV-C14, PSLV has launched multiple satellites into orbit with the maximum number being 10 during PSLV-C9 mission in April 2008.

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NASA Instruments Reveal Water Molecules on Lunar Surface

PASADENA, Calif. — NASA scientists have discovered water molecules in the polar regions of the moon. Instruments aboard three separate spacecraft revealed water molecules in amounts that are greater than predicted, but still relatively small. Hydroxyl, a molecule consisting of one oxygen atom and one hydrogen atom, also was found in the lunar soil. The findings were published in Thursday’s edition of the journal Science.

NASA’s Moon Mineralogy Mapper, or M3, instrument reported the observations. M3 was carried into space on Oct. 22, 2008, aboard the Indian Space Research Organization’s Chandrayaan-1 spacecraft. Data from the Visual and Infrared Mapping Spectrometer, or VIMS, on NASA’s Cassini spacecraft, and the High-Resolution Infrared Imaging Spectrometer on NASA’s Epoxi spacecraft contributed to confirmation of the finding. The spacecraft imaging spectrometers made it possible to map lunar water more effectively than ever before.

The confirmation of elevated water molecules and hydroxyl at these concentrations in the moon’s polar regions raises new questions about its origin and effect on the mineralogy of the moon. Answers to these questions will be studied and debated for years to come.

“Water ice on the moon has been something of a holy grail for lunar scientists for a very long time,” said Jim Green, director of the Planetary Science Division at NASA Headquarters in Washington. “This surprising finding has come about through the ingenuity, perseverance and international cooperation between NASA and the India Space Research Organization.”

From its perch in lunar orbit, M3’s state-of-the-art spectrometer measured light reflecting off the moon’s surface at infrared wavelengths, splitting the spectral colors of the lunar surface into small enough bits to reveal a new level of detail in surface composition. When the M3 science team analyzed data from the instrument, they found the wavelengths of light being absorbed were consistent with the absorption patterns for water molecules and hydroxyl.

“For silicate bodies, such features are typically attributed to water and hydroxyl-bearing materials,” said Carle Pieters, M3’s principal investigator from Brown University, Providence, R.I. “When we say ‘water on the moon,’ we are not talking about lakes, oceans or even puddles. Water on the moon means molecules of water and hydroxyl that interact with molecules of rock and dust specifically in the top millimeters of the moon’s surface.

The M3 team found water molecules and hydroxyl at diverse areas of the sunlit region of the moon’s surface, but the water signature appeared stronger at the moon’s higher latitudes. Water molecules and hydroxyl previously were suspected in data from a Cassini flyby of the moon in 1999, but the findings were not published until now.

“The data from Cassini’s VIMS instrument and M3 closely agree,” said Roger Clark, a U.S. Geological Survey scientist in Denver and member of both the VIMS and M3 teams. “We see both water and hydroxyl. While the abundances are not precisely known, as much as 1,000 water molecule parts-per-million could be in the lunar soil. To put that into perspective, if you harvested one ton of the top layer of the moon’s surface, you could get as much as 32 ounces of water.”

For additional confirmation, scientists turned to the Epoxi mission while it was flying past the moon in June 2009 on its way to a November 2010 encounter with comet Hartley 2. The spacecraft not only confirmed the VIMS and M3 findings, but also expanded on them.

“With our extended spectral range and views over the north pole, we were able to explore the distribution of both water and hydroxyl as a function of temperature, latitude, composition, and time of day,” said Jessica Sunshine of the University of Maryland. Sunshine is Epoxi’s deputy principal investigator and a scientist on the M3 team. “Our analysis unequivocally confirms the presence of these molecules on the moon’s surface and reveals that the entire surface appears to be hydrated during at least some portion of the lunar day.”

NASA’s Jet Propulsion Laboratory, Pasadena, Calif., manages the M3 instrument, Cassini mission and Epoxi spacecraft for NASA’s Science Mission Directorate in Washington. The Indian Space Research Organization built, launched and operated the Chandrayaan-1 spacecraft.

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