What Is The SSLV Rocket?

What Is SSLV?

The Small Satellite Launch Vehicle (SSLV) is an ISRO-developed small-lift launch vehicle with a payload capacity of 500 kg (1,100 lb) to low Earth orbit (500 km (310 mi)) or 300 kg (660 lb) to Sun-synchronous orbit (500 km (310 mi)) for launching small satellites, as well as the ability to support multiple orbital drop-offs. 

SSLV is designed with low cost and quick turnaround in mind, with launch-on-demand flexibility and minimum infrastructure needs. 

The SSLV-D1 launched from the First Launch Pad on August 7, 2022, but failed to reach orbit. 

SSLV launches to Sun-synchronous orbit will be handled in the future by the SSLV Launch Complex (SLC) at Kulasekharapatnam in Tamil Nadu. 

After entering the operational phase, the vehicle's manufacture and launch operations would be handled by an Indian consortium led by NewSpace India Limited (NSIL). 

What Is The Origin And Evolution Of SSLV?

The SSLV was created with the goal of commercially launching small satellites at a far lower cost and with a greater launch rate than the Polar Satellite Launch Vehicle (PSLV). 

SSLV has a development cost of 169.07 crore (US$21 million) and a production cost of 30 crore (US$3.8 million) to 35 crore (US$4.4 million). 

The expected high launch rate is based on mostly autonomous launch operations and simplified logistics in general. 

In comparison, a PSLV launch employs 600 officials, but SSLV launch procedures are overseen by a tiny crew of about six persons. 

The SSLV's launch preparation phase is predicted to be less than a week rather than months. 

The launch vehicle may be erected vertically, similar to the current PSLV and Geosynchronous Satellite Launch Vehicle (GSLV), or horizontally, similar to the decommissioned Satellite Launch Vehicle (SLV) and Augmented Satellite Launch Vehicle (ASLV). 

The vehicle's initial three stages employ HTPB-based solid propellant, with a fourth terminal stage consisting of a Velocity-Trimming Module (VTM) with eight 50 N reaction control thrusters and eight 50 N axial thrusters for altering velocity. 

SSLV's first and third stages (SS1) are novel, while the second stage (SS2) is derived from PSLV's third stage (HPS3). 

Where Is The SSLV Launch Complex?

Early developmental flights and those to inclined orbits would launch from Sriharikota, first from existing launch pads and ultimately from a new facility in Kulasekharapatnam known as the SSLV Launch Complex (SLC). 

In October 2019, tenders for production, installation, assembly, inspection, testing, and Self Propelled Launching Unit (SPU) were announced. 

When completed, this proposed spaceport at Kulasekharapatnam in Tamil Nadu would handle SSLV launches to Sun-synchronous orbit. 

What Is The History Of The SSLV?

Rajaram Nagappa recommended the development route of a 'Small Satellite Launch Vehicle-1' to launch strategic payloads in a National Institute of Advanced Studies paper in 2016. 

S. Somanath, then-Director of Liquid Propulsion Systems Centre, acknowledged a need for identifying a cost-effective launch vehicle configuration with 500 kg payload capacity to LEO at the National Space Science Symposium in 2016, and development of such a launch vehicle was underway by November 2017. 

The vehicle design was completed by the Vikram Sarabhai Space Centre (VSSC) in December 2018. 

All booster segments for the SSLV first stage (SS1) static test (ST01) were received in December 2020 and assembled in the Second Vehicle Assembly Building (SVAB). 

On March 18, 2021, the SS1 first-stage booster failed its first static fire test (ST01). 

Oscillations were detected about 60 seconds into the test, and the nozzle of the SS1 stage disintegrated after 95 seconds. 

The test was supposed to last 110 seconds. 

SSLV's solid first stage SS1 must pass two consecutive nominal static fire tests in order to fly. 

In August 2021, the SSLV Payload Fairing (SPLF) functional certification test was completed. 

On 14 March 2022, the second static fire test of SSLV first stage SS1 was performed at SDSC-SHAR and satisfied the specified test goals. 

How Will The Small Satellite Launch Vehicle (SSLV) Be Manufactured?

ISRO has begun development of a Small Satellite Launch Vehicle to serve the burgeoning global small satellite launch service industry. 

NSIL would be responsible for manufacturing SSLV via Indian industry partners. 

 

What Are The Unique Features Of The Small Satellite Launch Vehicle (SSLV)?

SSLV has been intended to suit "Launch on Demand" criteria while being cost-effective. 

It is a three-stage all-solid vehicle capable of launching up to 500 kilograms satellites into 500 km LEO. 

What Are The Expected Benefits Of The SSLV Rocket?

Reduced Turn-around Time Launch on Demand Cost Optimization.

Realization and Operation Ability to accommodate several satellites.

Minimum infrastructure required for launch Design practices that have stood the test of time.

The first flight from SDSC SHAR was originally scheduled during the fourth quarter of 2019. It occurred only in August of 2022.

Following the first developmental flights, ISRO plans to produce SSLV via Indian Industries through its commercial arm, NSIL. 

What Is The Operational Performance History Of The SSLV?

The SSLV's maiden developmental flight was place on August 7, 2022. 

SSLV-D1 was the name of the flying mission. 

The SSLV-D1 flight's mission goals were not met. 

The rocket featured three stages and a fourth Velocity Trimming Module (VTM). 

The rocket stood 34m tall, with a diameter of 2m, and a lift-off mass of 120t in its D1 version. 

The rocket launched EOS 02, a 135 kilograms Earth observation satellite, and AzaadiSAT, an 8 kg CubeSat payload designed by Indian students to promote inclusion in STEM education. 

The SSLV-D1 was planned to deploy the two satellite payloads in a circular orbit with a height of 356.2 km and an inclination of 37.2°. 

The ISRO's stated reason for the mission's failure was software failure. 

The mission software identified an accelerometer anomaly during the second stage separation, according to the ISRO. 

As a result, the rocket navigation switched from closed loop to open loop guidance. 

Despite the fact that this change in guiding mode was part of the redundancy incorporated into the rocket's navigation, it was not enough to save the mission. 

During open loop guiding mode, the last VTM stage only fired for 0.1s rather than the required 20s. 

As a result, the two satellites and the rocket's VTM stage were injected into an unstable elliptical 35676 km orbit. 

The SSLV-final D1's VTM stage had 16 hydrazine-fueled (MMH+MON3) thrusters. 

Eight of them were to regulate the orbital velocity and the other eight were to control the altitude. 

During the orbital insertion maneuvers, the VTM stage also controlled pitch, yaw, and roll. 

The SSLV-three D1's major stages all worked well. 

However, this was insufficient to provide enough thrust for the two satellite payloads to establish stable orbits. 

The VTM stage required to burn for at least 20 seconds to impart enough extra orbital velocity and altitude adjustments to put the two satellite payloads into their designated stable orbits. 

Instead, the VTM activated at 653.5s and shut down at 653.6s after lift-off. 

After the VTM stage was partially fired, the EOS 02 was released at 738.5s and AazadiSAT at 788.4s after liftoff. 

These failures occurred, causing the satellites to reach an unstable orbit and then be destroyed upon reentry. 

What Was The Performance Outcome Of The SSLV D1 Mission?

SSLV's maiden developmental flight. 

The mission goal was a circular orbit of 356.2 km height and 37.2° inclination. 

Two satellite payloads were carried on the trip. 

1. The 135-kilogram EOS-02 Earth observation satellite 
2. and the 8-kilogram AzaadiSAT CubeSat. 

Due to sensor failure and flaws in onboard software, the stage and two satellite payloads were put into an unstable elliptical orbit of 35676 km and then destroyed upon reentry. 

The mission software, according to the ISRO, failed to detect and rectify a sensor malfunction in the VTM stage. 

The last VTM stage only fired momentarily (0.1s). 

What Were The Overall Lessons From The SSLV-D1/EOS-02 Mission?

Mission ISRO developed a small satellite launch vehicle (SSLV) to launch up to 500 kilograms satellites into Low Earth Orbits on a 'launch-on-demand' basis . 

The SSLV-D1/EOS-02 Mission's first developmental flight was slated for August 7, 2022, at 09:18 a.m. 

(IST) from the Satish Dhawan Space Centre's First Launch Pad in Sriharikota. 

The SSLV-D1 mission would send EOS-02, a 135 kilograms satellite, into a low-Earth orbit 350 kilometers above the equator at an inclination of roughly 37 degrees. 

The mission also transports the AzaadiSAT satellite. 

SSLV is built with three solid stages weighing 87 t, 7.7 t, and 4.5 t. 

The satellite is inserted into the desired orbit using a liquid propulsion-based velocity trimming module. 

• SSLV is capable of launching Mini, Micro, or Nanosatellites (weighing between 10 and 500 kg) into a 500 km planar orbit. 

• SSLV gives low-cost on-demand access to space. 

• It has a quick turnaround time, the ability to accommodate numerous satellites, the ability to launch on demand, minimum launch infrastructure needs, and so on. 

SSLV-D1 is a 34-meter-tall, 2-meter-diameter vehicle with a lift-off mass of 120 tonnes. 

ISRO developed and built the EOS-02 earth observation satellite. 

This microsat class satellite provides superior optical remote sensing with excellent spatial resolution in the infrared spectrum. 

The bus configuration is based on the IMS-1 bus. 

AzaadiSAT is an 8U Cubesat that weighs around 8 kg. 

It transports 75 distinct payloads, each weighing roughly 50 grams and performing femto-experiments. 

These payloads were built with the help of female students from rural areas around the nation. 

The payloads were assembled by the "Space Kidz India" student team. 

A UHF-VHF Transponder operating on ham radio frequency to allow amateur radio operators to transmit speech and data, a solid state PIN diode-based Radiation counter to detect the ionizing radiation in its orbit, a long-range transponder, and a selfie camera are among the payloads. 

The data from this satellite was planned to be received using the ground system built by 'Space Kidz India.'  

Both satellite missions have failed as a result of the failure of SSLV-D1's terminal stage.

When Is The SSLV D2 Planned To Lift Off?

The SSLV's second developmental flight is planned for November of 2022. 

It is intended to transport four Blacksky Global satellites weighing 56 kg to a 500 km circular orbit with a 50° inclination.  

It will place the X-ray polarimeter satellite into low Earth orbit(LEO).

~ Jai Krishna Ponnappan.

Find Jai on Twitter | LinkedIn | Instagram

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PSLV-C52 Launch Of EOS-04, INSPIREsat-1 And INS-2TD

Watch the PSLV-C52/EOS-04 Launch Live Streaming. (Scheduled On: February 14, 2022, at 05:30 IST)

PSLV-C 52 Launch Updates:

ISRO's first launch of 2022, under the leadership of new Chairman S. Somanath, went off without a hitch, precisely positioning all three satellites in their assigned orbits. 

The PSLV C-52 of the Indian Space Research Organization lighted up the pre-dawn black sky and Pulicat Lake with thick orange fumes as it rose into the air, breaking the early stillness with the booming roar of the launch vehicle that had three satellites on board. 

ISRO's first launch of 2022, under the leadership of new Chairman S. Somanath, went off without a hitch, precisely positioning all three satellites in their assigned orbits. 

At 0617 IST, PSLV-C52 inserted EOS-04 into a 529km altitude sun-synchronous polar orbit, according to the Indian Space Research Organization. 

The PSLV C-52 was the PSLV's 54th flight and the 23rd mission to use the PSLV-XL variant. 

PSLV-C52 launched three satellites from the first launch pad at Satish Dhawan Space Centre in Sriharikota at 5.59 a.m on Monday, including its principal payload, the EOS-04 radar imaging satellite. 

• The EOS-04 satellite was put in a solar synchronous orbit 17 minutes after launch. 

• The rocket then inserted the two additional satellites, INS-2TD and Inspiresat-1, a minute later. 

• The fourth stage was passivated to remove residual propellants four minutes after lift-off, using mixed oxides of nitrogen (MON) passivation followed by mono methyl hydrazine (MMH) passivation, two propellants that power PSLV's upper stage. 

• The passivation process lasted ten minutes. 

• Passivation is the process of removing any remaining fuel from a rocket to avoid the higher stages from exploding. 

• The top stage burns inactively or vents the leftover propellants. 

PSLV's 54th flight and 23rd mission with six PSOM-XLs used the PSLV-XL configuration. 

"The main satellite, EOS-04, has been placed in a very exact orbit by PSLV-C52," Isro chairman S Somanath stated, congratulating the crew. 

The INS-2TD and INSPIREsat-1 co-passenger satellites have also been put in the proper orbits. 

This spacecraft will be one of the most valuable assets in the country's arsenal. 

We will come back with another PSLV launch very soon." 

"First and foremost, let me congratulate the PSLV crew for the exact inject of EOS-04," Srikanth remarked. 

The launch has re-energized the ISRO crew. 

The most awaited spacecraft, EOS-04, is an earth observation mission that will serve the country in agriculture, soil moisture, disaster management, disaster assessment, carbon inventory, forest and plantation management, and many other sectors with indigenously developed state-of-the-art technology SAR." 

"After separation, EOS-04's health is in fantastic condition. 

I'm pleased to report that the solar panels have been deployed autonomously and have begun to provide the desired electricity.... 

The satellite will be ready to offer the first sight of photos in a few days following calibration and outgassing. 

Many government services will be enhanced by the services. 

EOS-04 is a minor step toward the country's objective of opening the space sector with industry engagement in the form of build to print, as well as assemble and test. 

We were able to achieve a reasonable level of success in our endeavor." 

The launch's success was critical for ISRO, who had a quiet 2020 with just two launches, one of which, the GSLVF10, crashed shortly after launch. 

On Monday, the PSLV C-52, carrying the Earth Observation Satellite EOS 04, the INS-2TD, an ISRO technology demonstrator, and the INSPIREsat-1, a student satellite, launched from the Satish Dhawan Space Centre, SHAR, Sriharikota, at 5.59 a.m. 

The three satellites were separated and sent into their orbits 18 minutes later. 

"The EOS 04, the principal spacecraft, has been placed in a precise orbit. 

The co-passenger satellites have been positioned in the proper orbit," Mr. Somanath said, adding that ISRO would "be back with the next PSLV launch very shortly." 

• The EOS-4, a radar imaging satellite with a 10-year mission life, is intended to deliver high-quality pictures in all weather circumstances for agricultural, forestry, plantation, flood mapping, soil moisture, and hydrological applications. 

• According to ISRO, the satellite would acquire earth observation data in the C-band, complementing and supplementing data from the Resourcesat, Cartosat, and RISAT-2B series. 

• The INS-2TD will measure land and water surface temperatures, agricultural and forest delineation, and thermal inertia as a forerunner to the India-Bhutan joint satellite [INS 2-B]. 

• INSPIREsat-1 is a student satellite developed by the Indian Institute of Space Science and Technology in collaboration with the University of Colorado in the United States. 

• Its goal is to improve knowledge of ionosphere dynamics and coronal heating processes on the Sun. 

On Monday, Prime Minister Narendra Modi congratulated India's space experts on the success of the PSLV C52 mission launch. 

"Congratulations to our space experts on the successful launch of PSLV C52 mission," Mr. Modi tweeted. 

About The EOS-04 Earth Observation Satellite:

EOS-04 is a Radar Imaging Satellite that is intended to deliver high-quality photos in all weather circumstances for applications including agriculture, forestry, and plantations, soil moisture and hydrology, and flood mapping. 

The spacecraft will gather data in the C-Band band, completing observations made by the Resourcesat, Cartosat, and RISAT-2B series. The satellite has a ten-year operational life. 

The tentative launch time of the Polar Satellite Launch Vehicle, PSLV-C52, is planned for February 14, 2022, at 05:59 a.m from the Satish Dhawan Space Centre's First Launch Pad at Sriharikota. 

The Indian Space Research Organisation (ISRO) will launch PSLV-C52, an earth observation satellite, into orbit on February 14 at 5.59 a.m., with the countdown beginning on Sunday morning. This is the ISRO's first launch mission of the year. 

PSLV-C52 is planned to place the 1710 kg EOS-04 into a 529 km sun-synchronous polar orbit, according to ISRO. 

PSLV-C52 Mission Summary: 

1. The PSLV-C52 will be launched from Sriharikota's Satish Dhawan Space Centre's First Launch Pad. 

 

 

2. According to the space agency, EOS-04 is a Radar Imaging Satellite intended to deliver high-quality photos in all weather circumstances for applications such as agriculture, forestry and plantations, soil moisture and hydrology, and flood mapping. 

3. The mission will also carry two small satellites as co-passengers:

 

1. An Indian Institute of Space Science and Technology student satellite (INSPIREsat-1) in collaboration with the University of Colorado Boulder's Laboratory of Atmospheric and Space Physics,
2. And an ISRO technology demonstrator satellite, INS-2TD. 

PSLV-C52 will also carry an ISRO technology demonstration satellite (INS-2TD), which is a forerunner to the India-Bhutan Joint Satellite Program (INS-2B). 

• The 17.5-kilogram satellite will only be operational for six months. 

The launch comes months after the disastrous loss of the Earth Observation Satellite (EOS-03) in August of last year, which was unable to be deployed owing to a "technical problem." 

• A thermal imaging sensor on board the satellite will aid in the evaluation of land, water surface temperatures, vegetation delineation, and thermal inertia. 

The final payload is an 8.1-kilogram student satellite called INSPIRESat-1, which was designed by the Indian Institute of Space Science & Technology in collaboration with the University of Colorado's Laboratory of Atmospheric & Space Physics. 

• The satellite will help us better understand the dynamics of the ionosphere and the sun's coronal heating process. 

• It has a one-year operating lifespan. 

PSLV C-52 - The 54th Polar Satellite Launch Vehicle Launch

The PSLV's 54th mission will see it ascend to a Sun Synchronous Orbit height of 529 kilometers above the Earth's surface, where it will deploy the Earth Observation Satellite. 

• The PSLV is an Indian-designed third-generation launch vehicle that can carry up to 1,750 kg of cargo to 600 km altitude Sun-Synchronous Polar Orbits. 
• 

• In 2008, the four-stage rocket successfully launched Chandrayaan-1 to the Moon, and in 2013, the Mars Orbiter Spacecraft to Mars. 

• The liftoff mass of the 44-meter-tall vehicle is 320 tons. 

Stages Of The PSLV-C52:

• PSLV's first stage is powered by the S139 solid rocket motor, which is supplemented by six solid strap-on boosters, 

• While the second stage is powered by the Vikas engine, which was developed in India. 

• The PSLV's third stage is a solid rocket motor that gives high thrust to the higher stages following the launch's atmospheric phase, while the fourth stage is made up of two Earth-storable liquid engines. 

ISRO's Upcoming Missions

In the next three months, ISRO plans to launch five significant satellites in order to reclaim its lost ground in space operations, despite stiff competition from China and commercial companies such as SpaceX, which plans to launch one satellite per week in 2022. 

• ISRO will launch OCEANSAT-3 and INS 2B ANAND on PSLV C-53 in March and SSLV-D1 Micro SAT in April 2022, after the PSLV-C52 mission. 

• ISRO will also launch GSAT-21, New Space India Limited's first fully sponsored satellite (NSIL). 

• The space agency, which recently appointed renowned rocket scientist S Somnath as its new leader, has 19 missions slated for flight in 2022. 

• Eight launch vehicle flights, seven spacecraft missions, and four technology demonstration missions are among them. 

In August, the agency will launch its ambitious Chandrayaan-3 mission to the Moon, aiming for Gaganyaan's first uncrewed trip, the country's first astronaut mission.

~ Jai Krishna Ponnappan.

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How Can Atomic Clocks Help Humans Arrive On Mars On Time?

Autonomous Navigation - Overcoming Technological Limitations

NASA navigators are assisting in the development of a future in which spacecraft may safely and independently travel to destinations such as the Moon and Mars.

• Today, navigators guide a spacecraft by calculating its position from Earth and transmitting the data to space in a two-way relay system that may take minutes to hours to give instructions. 

• This mode of navigation ensures that our spacecraft remain connected to the earth, waiting for instructions from our planet, no matter how far a mission goes across the solar system.

• This constraint will obstruct any future crewed voyage to another planet. 

How can astronauts travel to destinations distant from Earth if they don't have direct control over their path? 

And how will they be able to land properly on another planet if there is a communication delay that slows down their ability to alter their trajectory into the atmosphere?

The Deep Space Atomic Clock, a toaster-sized clock developed by NASA, seeks to provide answers to these concerns. 

• It's the first GPS-like device that's tiny enough to go on a spaceship and steady enough to operate. 

• The technological demonstrated allows the spaceship to determine its location without relying on data from Earth.

• The clock will be sent into Earth's orbit for a year in late June on a SpaceX Falcon Heavy rocket, where it will be tested to see whether it can assist spacecraft in locating themselves in space.

If the Deep Orbit Atomic Clock's first year in space goes well, it may open the way for one-way navigation in the future, when humans can be led over the Moon's surface by a GPS-like system or safely fly their own missions to Mars and beyond.

• Navigators on Earth guide every spaceship traveling to the furthest reaches of the universe. 

• By allowing onboard autonomous navigation, or self-driving spaceship, the Deep Space Atomic Clock will alter that.

Deep Space Navigation

Atomic clocks in space are not a novel concept. 

• Every GPS gadget and smartphone uses atomic clocks on satellites circling Earth to calculate its position. 

• Satellites transmit signals from space, and the receiver triangulates your location by calculating the time it takes for the signals to reach your GPS.

• At the moment, spacecraft beyond Earth's orbit do not have a GPS to help them navigate across space. 

GPS satellites' atomic clocks aren't precise enough to transmit instructions to spacecraft, where even a fraction of a second may mean missing a planet by kilometers.

• Instead, navigators transmit a signal to the spaceship, which bounces it back to Earth, using massive antennas on Earth.

• Ground-based clocks keep track of how long it takes the signal to complete this two-way trip. 

• The length of time informs them how far away and how quickly the spaceship is traveling. 

• Only then will navigators be able to give the spacecraft instructions, instructing it where to travel.

• "It's the same idea as an echo," Seubert said. "If I scream in front of a mountain, the longer it takes for the echo to return to me, the farther away the mountain is."

Two-way navigation implies that a mission must wait for a signal containing instructions to traverse the enormous distances between planets, no matter how far into space it travels. 

• It's a procedure made famous by Curiosity's arrival on Mars, when the world waited 14 minutes for the rover to transmit the word that it had landed safely with mission headquarters. 

• A one-way communication between Earth and Mars may take anything from 4 to 20 minutes to get between the planets, depending on where they are in their orbits.

• It's a sluggish, arduous method of navigating deep space, one that clogs up NASA's Deep Space Network's massive antennae like a busy phone line. 

• A spaceship traveling at tens of thousands of kilometers per hour may be at a completely different location by the time it "knows" where it is during this interaction.

Atomic Clocks To Compute Precise Locations In Space

This two-way system may be replaced with an atomic clock small enough to go on a mission but precise enough to provide correct instructions. 

• A signal would be sent from Earth to a spaceship in the future. 

• The Deep Space Atomic Clock aboard, like its Earthly counterparts, would measure the time it took for that signal to reach it. 

• After that, the spacecraft could compute its own location and course, effectively directing itself.

Having a clock aboard would allow onboard radio navigation, which, when coupled with optical navigation, would provide astronauts with a more precise and safe method to navigate themselves.

• This one-way navigation technique may be used on Mars and beyond. 

• By sending a single signal into space, DSN antennas would be able to connect with many missions at the same time. 

• The new technique has the potential to enhance GPS accuracy on Earth. 

• Additionally, several spacecraft equipped with Deep Space Atomic Clocks might circle Mars, forming a GPS-like network that would guide robots and people on the surface.

The Deep Space Atomic Clock will be able to assist in navigation not just on Earth, but also on distant planets. Consider what would happen if we had GPS on other planets.

• Burt and JPL clock scientists Robert Tjoelker and John Prestage developed a mercury ion clock that, like refrigerator-size atomic clocks on Earth, retains its stability in space. 

• The Deep Space Atomic Clock was shown to be 50 times more accurate than GPS clocks in lab testing. Every ten million years, there is a one-second mistake.

• The clock's ability to stay steady in orbit will be determined by its demonstration in space. 

• A Deep Space Atomic Clock may launch on a mission as early as the 2030s if it succeeds. 

• The first step toward self-driving spaceship capable of transporting people to distant planets.

General Atomics Electromagnetic Systems of Englewood, Colorado supplied the spacecraft for the Deep Space Atomic Clock. 

It is supported by NASA's Space Technology Mission Directorate's Technology Demonstration Missions program and NASA's Human Exploration and Operations Mission Directorate's Space Communications and Navigations program. The project is overseen by JPL.

~ Jai Krishna Ponnappan

Courtesy - NASA.gov

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