NEW DELHI: 

The world's lightest satellite made by Indian students will be carried on the back of a rocket launched by the ISRO today. It's on the house - not a single rupee will be charged by the Indian Space Research Organisation (ISRO) for the task. The satellite designed and built by students who work with a private organisation called "Space Kidz India" in Chennai weighs less than a wooden chair at only 1.26 kg.

It cost Rs. 12 lakh to make and was made ready in six days, though the group perfected the technology over a span of six years, said Srimathy Kesan, a 45-year-old professional who steered this motley group of 20-something at Space Kidz India.

The Kalamsat-V2 is the lightest satellite in the world, the ISRO said, adding today's launch will also mark another milestone - it's the first satellite designed and built by an Indian private entity and Space Kidz India to be launched by ISRO.

A 64-gram earlier version of the Kalamsat nicknamed "gulab jamun" because of its puny size was launched by the National Aeronautics and Space Administration (NASA) in 2017. But it never reached orbit.

The main passenger in today's launch of the space agency's workhorse, Polar Satellite Launch Vehicle (PSLV), is a 740-kg satellite called Microsat-R that will be used to take high-resolution photos of the Earth for defence research.

The 44.4-metre-long PSLV that weighs 260 tonnes will attempt to take both satellites into orbit on its 46th launch.

The ISRO will also convert the last stage of the rocket, which actually turns into space debris, into a working experimental platform. This is a new way of creating wealth from waste in space as the debris would now remain functional and help in research.

The countdown began ahead of the launch from the Sriharikota spaceport in Andhra Pradesh.

"In this mission, the fourth stage... will be moved to higher circular orbit so as to establish an orbital platform for carrying out experiments," ISRO chairman Kailasavadivoo Sivan told NDTV.

In its last mission on November 29 last year, the ISRO successfully placed India's Earth-observation satellite HysIS onboard the PSLV C43 into orbit.

Quelle: NDTV

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Update: 25.01.2019

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Launch of India debuts new version of workhorse PSLV

A new variant of India’s workhorse Polar Satellite Launch Vehicle with two strap-on solid rocket boosters and an upper stage converted into an experiment-carrying platform debuted Thursday with a launch into polar orbit.

The 145-foot-tall (44-meter) PSLV lifted off from the Satish Dhawan Space Center, located on Sriharikota Island on India’s east coast, at 1807 GMT (1:07 p.m. EST) Thursday on the first Indian space launch of 2019.

The launch occurred at 11:37 p.m. Indian Standard Time, making it a rare night launch from India’s spaceport.

The primary payload on the flight was an Indian military Earth observation satellite named Microsat-R. But a major objective of the launch was to demonstrate using the PSLV’s fourth stage as an experiment base in orbit after deploying the Microsat-R spacecraft.

On previous PSLV missions, the liquid-fueled fourth stage was deactivated after finishing its satellite deployment sequence. Most other rockets do the same, either leaving their spent rocket stages in orbit or deorbiting them to burn up in Earth’s atmosphere.

The Indian Space Research Organization, India’s national space agency, said the fourth stage on Thursday’s launch carried a payload developed by Indian students named  Kalamsat. The tiny payload weighs only a couple of pounds and was planned to only be active around 15 hours after the launch before its batteries are drained, but future PSLV upper stages could include solar panels to generate electricity for longer experiment durations.

Developed by a Chennai-based organization named Space Kidz India, the Kalamsat payload uses commercial off-the-shelf computer and communications systems and will broadcast data to Earth from the PSLV upper stage. A precursor experiment from Space Kidz India launched on a NASA-sponsored suborbital sounding rocket flight to space from Wallops Island, Virginia, in 2017.

Thursday’s mission was also the first to use a new configuration of India’s Polar Satellite Launch Vehicle with two strap-on boosters. Previous PSLV flights used no boosters or flew with six motors to provide extra thrust at liftoff.

The new rocket configuration, named the PSLV-DL, will give Indian officials an intermediate option to fly the rocket with fewer boosters if a mission does not need the full lifting performance of six strap-on motors, a measure that adds flexibility for ISRO managers and could save money.

The PSLV’s solid rocket boosters burn around 12.2 metric tons — more than 26,000 pounds — of pre-packed solid propellant in the first 70 seconds of the flight, then jettison from the rocket’s core stage to fall into the Bay of Bengal.

Each booster stands 39 feet (12 meters) tall and measures around 3.3 feet (1 meter) in diameter, generating approximately 158,000 pounds of thrust. With two boosters supplementing the PSLV’s solid-fueled core stage, the PSLV-DL fired off the launch pad with around a million pounds of thrust.

Heading on an initial track southeast from Sriharikota, the twin boosters separated around 70 seconds after liftoff, and the PSLV’s first stage burned out and jettison at T+plus 1 minute, 49 seconds, followed immediately by ignition of the rocket’s liquid-fueled second stage. The second stage’s Vikas engine, consuming hydrazine and nitrogen tetroxide, produced around 180,000 pounds of thrust for a two-and-a-half minute burn, during which the PSLV’s payload shroud released in a clamshell-like fashion once the launcher reaches space.

After bending its trajectory toward the south to bypass an overflight of Sri Lanka, the PSLV fired its solid-fueled third stage next, followed by ignition of the twin-engine fourth stage — also burning hydrazine — at T+plus 8 minutes, 18 seconds.

The fourth stage, known as the PS4, shut down at T+plus 12 minutes, 46 seconds, and deployed the Microsat-R spacecraft at T+plus 13 minutes, 33 seconds. ISRO officials confirmed the successful deployment of Microsat-R.

The Hindu, an English-language newspaper in India, reported the Microsat-R satellite comes from the Defense Development and Research Organization — DDRO — the research and development agency of the Indian military. The roughly 1,631-pound (740-kilogram) satellite was to be deployed in an unusually-low orbit around 170 miles (274 kilometers) above Earth, the Hindu reported.

ISRO provided no details about Microsat-R in a press kit released before the launch, other than to describe it as an “imaging satellite.”

Microsat-R separated in an orbit inclined around 96.6 degrees to the equator, according to the ISRO press kit.

Two additional burns by the PS4 fourth stage engines, each programmed to last around 15 seconds, were planned approximately 54 minutes and 1 hour, 40 minutes, after liftoff to raise the rocket’s orbit to an altitude of 279 miles (450 kilometers) at an inclination of 98.8 degrees. In that orbit, the fourth stage was to begin its mission as an experiment platform with the Kalamsat payload.

Thursday’s launch marked the 46th flight of a Polar Satellite Launch Vehicle since 1993. All but two of the launches have been successful.

Quelle: SN

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Quelle: ISRO

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PSLV launches debut orbital platform use of the fourth stage

India’s Polar Satellite Launch Vehicle deployed a military reconnaissance satellite and carried out a technology demonstration mission Thursday, flying in a new configuration and testing its upper stage as an experimental satellite platform. PSLV lifted off from the Satish Dhawan Space Centre at 23:38 local time (18:07 UTC).

Thursday’s launch, the forty-sixth overall for the Polar Satellite Launch Vehicle (PSLV), marked the maiden flight of the rocket’s new PSLV-DL configuration. Filling a gap in payload capacity between two of the rocket’s existing configuration, the PSLV-DL will help reduce the cost of India’s access to space. Its first payload consists of a demonstration satellite built around the rocket’s upper stage, testing this concept for future applications, and a military spacecraft with an imaging payload.

The PSLV that performed Thursday’s launch was vehicle number C44. PSLV was developed by the Indian Space Research Organisation (ISRO) and first flew in September 1993. It was the third rocket that ISRO developed to launch satellites, following on from the earlier Satellite Launch Vehicle (SLV) and Augmented Satellite Launch Vehicle (ASLV). The four-stage rocket uses a mixture of solid and liquid-fuelled propulsion.

The name Polar Satellite Launch Vehicle reflects that the rocket was originally designed for missions to near-polar sun-synchronous orbits, commonly used for Earth observation and low Earth orbit scientific satellites as well as for many other missions. Despite this PSLV has frequently been used to deploy spacecraft to other orbits, including geosynchronous communications, weather and navigation satellites and probes bound for the Moon and Mars.

Prior to Thursday’s introduction of the PSLV-DL, the PSLV has flown in three different configurations. All of these have the same four stages at their core, varying the boosters that are strapped to the first stage of the vehicle. PSLV’s first stage, the PS1, uses an S-138 solid rocket motor. The liquid-fuelled second stage, known as PS2 or L-40, is powered by a Vikas-4B engine. Another solid motor, an S-7, comprises the third stage or HPS3. The rocket’s fourth stage – PS4 or L-2.5 – has two restartable liquid-fuelled engines for precise orbital insertion.