New Delhi:

India docked two satellites in space on Thursday, a key milestone for the country’s ambitions of a space station and manned Moon mission. “India docked its name in space history,” said the Indian Space Research Organisation (ISRO) on X. ISRO shared a behind-the-scenes video today to showcase the lead-up to the historic feat – dubbed as SpaDeX, or Space Docking Experiment.

The video shows a packed mission control room for the coverage of the orbital docking.

A man was heard explaining the whole process: “The mission director will be giving a go-ahead for the subsequent motion of spacecraft from 3 meters till docking. The command will be given for the subsequent phase wherein the spacecraft starts at three meters. With a constant velocity of 10 mm per second, it is approaching other spacecraft for docking to take place.”

ISRO successfully completed docking of two SPADEX satellites (SDX-01 & SDX-02) in the early hours of 16 January, 2025.#SPADEX #ISRO pic.twitter.com/UJrWpMLxmh

— ISRO (@isro) January 17, 2025

The satellites, weighing 220 kilograms each, blasted off on December 30, last year, on a single rocket from Andhra Pradesh’s Sriharikota launch site. Later they separated.

The two satellites were manoeuvred back together on Thursday in a “precision” process resulting in a “successful spacecraft capture”.

Back at the control room, the man announced, amid a round of applause, “The capture event is nominal… Both the spacecraft are captured. the capture has been completed.”

Congratulating everyone involved in the mission for accomplishing the “historic docking for the first time in the country”, ISRO chairman V Narayanan said, “During the last 15 days, excellent dedicated activities were carried out and today we have got a historic docking and on this occasion, let me congratulate each one of you. Today, we are a proud nation carrying this technology with us which is required for our future missions, including Chandrayaan-4, crewed mission to moon. This is the first stepping stone towards those important activities”.

The docking experiment is crucial for the smooth conduct of the country’s ambitious future missions, including Chandrayaan-4, Gaganyaan, setting up a space station and landing an astronaut on the moon. Last October, the government announced that India will have its own Space Station by 2035, known as the “Bharatiya Antriksh Station”.

The PSLV C60 rocket carrying two small satellites, SDX01 (Chaser) and SDX02 (Target), along with 24 payloads, had lifted off from the first launchpad of the Satish Dhawan Space Centre, and about 15 minutes after liftoff, the two small spacecraft weighing about 220 kg each were launched into a 475-km circular orbit as intended.

India has become the fourth country to achieve the milestone after Russia, the United States and China.

Two earlier docking attempts by ISRO were postponed due to technical issues.

Hyderabad-based Anant Technologies has been partnering with ISRO for several years including in the successful docking mission. ATL’s chairman and managing director P. Subba Rao at the assembly of PSLV C60 which carried two satellites as part of the agency’s SpaDex mission.
| Photo Credit: By Arrangement

Ananth Technologies Limited (ATL), a leading player in India’s space industry functioning from Hyderabad, said that the successful precision docking mission by Indian Space Research Organisation (ISRO) reinforces the agency’s unwavering commitment to push the boundaries of space exploration and technological innovation.

“The successful docking highlights India’s growing capabilities in advanced space operations and showcases the dedication and expertise of ISRO’s scientists and engineers. We are proud to have played a crucial role in the SpaDeX mission,” said chairman and managing director P. Subba Rao through a press release issued on Thursday (January 16, 2025).

The firm had delivered critical components, including Rendezvous Processing Units (RPU) and DC-DC converters for SDX01 and SDX02 for satellite sub-systems. For satellite integration, it undertook the Assembly, Integration, and Testing (AIT) of the satellites at its world-class private-sector satellite manufacturing facilities.

ATL also took up AIT of various PSLV-C60 subassemblies and had supplied 29 key subsystems, including Data Acquisition Units, Transmitters, Power Modules, NAVIC processor and control modules.

“ISRO’s success inspires all of us in the space ecosystem to continue striving for excellence and innovation. SpaDeX underscores its unwavering dedication to innovation and self-reliance in space technology, positioning India among the elite nations mastering complex orbital operations. This mission advances key objectives such as lunar exploration, sample return missions, and establishing the Bharatiya Antariksh Station (BAS),”he said.

ATL has been collaborating with ISRO for over three decades contributing to success of 102 satellites and 82 launch vehicles by playing a key role in making satellite systems, launch vehicle components, and mission-critical technologies. While it is headquartered in Hyderabad, it operates advanced facilities in Thiruvananthapuram for the fabrication, assembly, and testing of launch vehicle subsystems and satellites, the release added.

Hyderabad-based Anant Technologies has been partnering with ISRO for several years including in the successful docking mission. ATL’s chairman and managing director P. Subba Rao at the assembly of PSLV C60 which carried two satellites as part of the agency’s SpaDex mission.
| Photo Credit: By Arrangement

Ananth Technologies Limited (ATL), a leading player in India’s space industry functioning from Hyderabad, said that the successful precision docking mission by Indian Space Research Organisation (ISRO) reinforces the agency’s unwavering commitment to push the boundaries of space exploration and technological innovation.

“The successful docking highlights India’s growing capabilities in advanced space operations and showcases the dedication and expertise of ISRO’s scientists and engineers. We are proud to have played a crucial role in the SpaDeX mission,” said chairman and managing director P. Subba Rao through a press release issued on Thursday (January 16, 2025).

The firm had delivered critical components, including Rendezvous Processing Units (RPU) and DC-DC converters for SDX01 and SDX02 for satellite sub-systems. For satellite integration, it undertook the Assembly, Integration, and Testing (AIT) of the satellites at its world-class private-sector satellite manufacturing facilities.

ATL also took up AIT of various PSLV-C60 subassemblies and had supplied 29 key subsystems, including Data Acquisition Units, Transmitters, Power Modules, NAVIC processor and control modules.

“ISRO’s success inspires all of us in the space ecosystem to continue striving for excellence and innovation. SpaDeX underscores its unwavering dedication to innovation and self-reliance in space technology, positioning India among the elite nations mastering complex orbital operations. This mission advances key objectives such as lunar exploration, sample return missions, and establishing the Bharatiya Antariksh Station (BAS),”he said.

ATL has been collaborating with ISRO for over three decades contributing to success of 102 satellites and 82 launch vehicles by playing a key role in making satellite systems, launch vehicle components, and mission-critical technologies. While it is headquartered in Hyderabad, it operates advanced facilities in Thiruvananthapuram for the fabrication, assembly, and testing of launch vehicle subsystems and satellites, the release added.

Hyderabad-based Anant Technologies has been partnering with ISRO for several years including in the successful docking mission. ATL’s chairman and managing director P. Subba Rao at the assembly of PSLV C60 which carried two satellites as part of the agency’s SpaDex mission.
| Photo Credit: By Arrangement

Ananth Technologies Limited (ATL), a leading player in India’s space industry functioning from Hyderabad, said that the successful precision docking mission by Indian Space Research Organisation (ISRO) reinforces the agency’s unwavering commitment to push the boundaries of space exploration and technological innovation.

“The successful docking highlights India’s growing capabilities in advanced space operations and showcases the dedication and expertise of ISRO’s scientists and engineers. We are proud to have played a crucial role in the SpaDeX mission,” said chairman and managing director P. Subba Rao through a press release issued on Thursday (January 16, 2025).

The firm had delivered critical components, including Rendezvous Processing Units (RPU) and DC-DC converters for SDX01 and SDX02 for satellite sub-systems. For satellite integration, it undertook the Assembly, Integration, and Testing (AIT) of the satellites at its world-class private-sector satellite manufacturing facilities.

ATL also took up AIT of various PSLV-C60 subassemblies and had supplied 29 key subsystems, including Data Acquisition Units, Transmitters, Power Modules, NAVIC processor and control modules.

“ISRO’s success inspires all of us in the space ecosystem to continue striving for excellence and innovation. SpaDeX underscores its unwavering dedication to innovation and self-reliance in space technology, positioning India among the elite nations mastering complex orbital operations. This mission advances key objectives such as lunar exploration, sample return missions, and establishing the Bharatiya Antariksh Station (BAS),”he said.

ATL has been collaborating with ISRO for over three decades contributing to success of 102 satellites and 82 launch vehicles by playing a key role in making satellite systems, launch vehicle components, and mission-critical technologies. While it is headquartered in Hyderabad, it operates advanced facilities in Thiruvananthapuram for the fabrication, assembly, and testing of launch vehicle subsystems and satellites, the release added.

In-space docking technology is essential when multiple rocket launches are required to achieve common mission objectives. Through this mission, India is marching towards becoming the fourth country in the world to have space docking technology. File
| Photo Credit: PTI

“The two Space Docking Experiment (SpaDeX) satellites that ISRO is hoping to unite are at a distance of 1.5 km and will be brought much closer on January 11,” the space agency said on Friday (January 10, 2025).

The SpaDeX space docking experiment has so far missed two publicly announced schedules, on January 7 and January 9.

“Spacecrafts are at a distance of 1.5 km and on hold mode. Further drift to 500 m is planned to be achieved by tomorrow morning,” ISRO said in a post on ‘X’.

This announcement came a day after the space agency shared that the drift between satellites that had caused the postponement of the docking experiment for the second time had been arrested and they were put in a slow drift course to move closer to each other.

ISRO successfully launched the Space Docking Experiment (SpaDeX) mission on December 30, 2024.

The PSLV C60 rocket carrying two small satellites, SDX01 (Chaser) and SDX02 (Target), along with 24 payloads, had lifted off from the first launchpad of the Satish Dhawan Space Centre in Sriharikota, and about 15 minutes after liftoff, the two small spacecraft weighing about 220 kg each were launched into a 475-km circular orbit as intended.

After the launch, ISRO has been preparing for the docking, which requires multiple steps/stages.

Docking in space is a complex process, which so far has been mastered by only three other countries — the U.S., Russia and China.

On January 6, a day before the first docking attempt was scheduled, ISRO announced its postponement to January 9, stating that the docking process requires further validation through ground simulations based on an abort scenario identified.

A day ahead of the docking planned on January 9, the space agency had initiated the drift on Spacecraft A (chaser) to move closer from 500 m to 225 m. But shortly after that it announced another postponement of docking, saying that — while making a maneuver to reach 225 m between satellites, the drift was found to be more than expected, post non-visibility period.

According to ISRO, SpaDeX mission is a cost-effective technology demonstrator mission for the demonstration of in-space docking using two small spacecraft that were launched by PSLV. This technology is essential for India’s space ambitions such as Indian on Moon, sample return from the Moon, the building and operation of Bharatiya Antariksh Station (BAS), etc.

In-space docking technology is essential when multiple rocket launches are required to achieve common mission objectives. Through this mission, India is marching towards becoming the fourth country in the world to have space docking technology.

Photo: YouTube/@isroofficial5866

ISRO has once again postponed the Space Docking Experiment (SpaDEx) involving two satellites, citing excessive drift during a crucial manoeuvre.

The SpaDEx was supposed to take place on January 9.

“While making a manoeuvre to reach 225 m between satellites the drift was found to be more than expected, post non-visibility period. The planned docking for tomorrow is postponed. Satellites are safe. Stay tuned for updates,” ISRO said in a post on ‘X’ on Wednesday (January 8, 2025).

This is the second time when the ISRO postponed the SpaDEx.

The space agency had initially planned it on January 7, 2025, which was cancelled and postponed to Thursday (January 9, 2025), which again got cancelled.

The Space Docking Experiment (SPADEX) is a pivotal project, which is designed to develop and demonstrate the technology needed for spacecraft rendezvous, docking, and undocking using two small satellites, the space agency said.

“SpaDeX will serve as a milestone in advancing India’s capabilities in space docking, a critical technology for future space missions including satellite servicing, space station operations, and interplanetary missions,” ISRO said in an explainer.

New Delhi:

In a first for India, life has sprouted on a craft sent into space by the country.

Cowpea seeds sent on the PS4-Orbital Experiment Module (POEM), or the Bharatiya Space Lab, have germinated in the near zero-gravity and enclosed surroundings of space – and leaves are also expected to grow soon.

This experiment was part of the SpaDeX or space docking experiment launched on December 30, 2024, using the Polar Satellite Launch Vehicle (PSLV).

In a post on X, the ISRO handle wrote, “Life sprouts in space! VSSC’s CROPS (Compact Research Module for Orbital Plant Studies) experiment onboard PSLV-C60 POEM-4 successfully sprouted cowpea seeds in 4 days. Leaves expected soon.”

ISRO Chairman Dr S Somanath told NDTV that the successful experiment could play a key role in the human space mission (Gaganyaan) and the plan to build an Indian space station (Bharatiya Antariksha Station).

“It is very exciting to see life sprouting on the Bharatiya Space Lab. This cowpea germination test is the maiden attempt to try and understand, through our own experiments, how life works in space. It also gives confidence in the environment control and life support system (ECLSS) deployed on board the Indian orbital module,” Dr Somanath said.

“This one small step for POEM may help write a whole new novel on life support for Gaganyaan and the Bharatiya Antariksha Station… a big learning for India from a small experiment, since no one shares these seemingly simple but challenging bits of complex life-support technologies,” he added.

Objective

For the in-house team of ISRO’s Vikram Sarabhai Space Centre (VSSC), Thiruvananthapuram, the objective was to demonstrate how cowpea seeds germinate in the near-zero-gravity environment of space. What made the experiment challenging was the fact that seedlings lose orientation when grown in microgravity conditions.

“Studying plant growth in space is new to ISRO and the 15-member team is very excited to see the results,” said T Latha, VSSC Deputy Director, who is heading the experiment. She says cowpea (Vigna unguiculata, known as ‘lobia’ in Hindi) was chosen as its seeds can germinate and grow leaves in less than a week.

The POEM module is also carrying two other live biology experiments that will attempt to grow gut bacteria and spinach cells.

ISRO Chairman S. Somanath with senior ISRO scientists and the directors of various centres during a press conference after successfully launching the first SpaDeX mission, Sriharikota, December 30, 2024.
| Photo Credit: PTI

There will be a series of space docking experiments before the Indian Space Research Organisation embarks on its Chandrayaan-4 mission to bring soil samples from the moon to the earth, ISRO has said.

On December 30, 2024, the C60 mission of the Polar Satellite Launch Vehicle (PSLV) placed two satellites, each weighing 220 kg, in orbit. They will rendezvous and dock with each other as part of ISRO’s first Space Docking Experiment (SpaDeX).

ISRO Chairman S. Somanath said “the nominal time” for the docking “will be approximately January 7.”  He added, “The two SpaDeX satellites have moved one behind the other, so over a period of time, they will pick up further distance. The distance will increase by 20 km over the next few days and then the rendezvous and docking process will start.”

For Chandrayaan-4, ISRO will launch the mission’s modules in two Launch Vehicle Mark-3 (LVM-3) rockets. At various points during the mission, the modules will undergo a series of docking and undocking manoeuvres before finally transporting a canister of lunar soil safely back to the earth.

A crucial technology

Mr. Somanath had said on December 31, “2025 will be an exciting year as ISRO will launch four GSLV rockets, three PSLV launches as well as an SSLV launch.” (GSLV is short for Geosynchronous Satellite Launch Vehicle and SSLV for Small Satellite Launch Vehicle).

Docking is a crucial technology for India to master for Chandrayaan-4 as well as its forthcoming orbital Bharatiya Antariksh Station (BAS), expected to be ready by 2035, and for its goal to send an Indian astronaut to the moon.

Chandrayaan-4 study director P. Veeramuthuvel said, “Docking is important for all future missions of ISRO because you cannot launch everything in one go. So you need docking of modules in space. … There will be five modules in BAS, all of which require docking. This technology is crucial for bringing back the lunar soil samples and for India’s constant presence in space.”

The two satellites in the current SpaDeX mission are in a circular orbit 475 km above the earth. “At that height, the two satellites will be moving at a speed of 28,000 km an hour,” said former ISRO associate director B.R. Guruprasad. “You must establish the orbit of both the satellites. To bring them together, you have to match their speeds. It is not easy to match and adjust their speeds precisely, make them come close to each other and then dock. There lies the challenge.”

Chandrayaan-4 mission profile

Mr. Veeramuthuvel said at the International Astronautical Congress at Milan, Italy, in October 2024 one LVM-3 would carry the transfer and reentry modules and the other would carry the descend and ascend modules. The four modules together would weigh about 9.2 tonnes.

The pairs will dock in the geosynchronous transfer orbit and travel to lunar orbit.  Here, the transfer and reentry modules will remain in orbit while the descent and ascent modules will reach the moon’s surface. The descent module will undock from the ascent module and deploy a robotic scoop to obtain a 3 kg sample of the lunar surface and subsurface, and place it in a cartridge. The ascent module will then lift off from the moon with the sealed cartridge.

“The descent module will be dead after the ascent module lifts off,” Mr. Veeramuthuvel said.

The ascent module will dock with the transfer module, transfer the cartridge, and undock to stay in a low lunar orbit. The reentry and transfer modules will then together travel towards the earth. In the final step, the transfer module will eject the reentry module, which will descend to the ground for retrieval.

New:

The skies over Sriharikota, Andhra Pradesh, were lit up at 10 pm today with the 62nd launch of the PSLV. The 25-hour countdown which started on Sunday, ended with the rocket lifting off from the First Launch Pad at this spaceport, exuding blinding orange fumes that streaked through the night sky. Within 15 minutes, it placed the twin space docking satellites into space. 

Amid much applause, Dr S Somanath, chairman of ISRO (Indian Space Research Organisation) announced that they have got the “right orbit”. 

The last stage of the launch vehicle was continuing to work to lower its orbit for the POEM (PS4-Orbital Experiment Module), which would conduct tests in the vacuum of space. 

ISRO has announced that the space docking experiment will most likely take place on January 7. The two satellites will be mated in space when they would be travelling at ten times the velocity of a bullet. 

The Spacecraft A (SDX01) or the ‘Chaser’ and Spacecraft B (SDX02) or the ‘Target’ would be merged together at an altitude of about 470 km after travelling at the same speed and distance.

A successful docking and undocking would make India the world’s fourth nation to have space docking technology, ISRO has said.

Explaining the process, Dr Somnath, in an exclusive interview to NDTV, said: “When you have multiple objects in space that need to be brought together for a specific purpose, a mechanism called docking is required. Docking is the process by which two space objects come together and connect”. 

This, he said, can be done using various approaches — soft mechanisms, hard mechanisms, or pressurised compartments for human transfer. 

“For example, on the International Space Station, crew modules dock at the station, equalise pressure, and transfer people,” he told NDTV.

This was the 99th rocket launch from the Satish Dhawan Centre of Sriharikota and it had a glorious lift off, placing SpaDeX satellites in the best orbit. 

The next steps — docking and the 24 experiments — will be conducted over the next few weeks.

With this, ISRO, which had started 2024 with a PSLV launch on Jan 1, ends it on a high note as well.

Two spacecraft that would aid ISRO in demonstrating space docking, a critical technology for future space missions got separated successfully and were placed into the desired low earth orbit late on Monday night, ISRO said.

“PSLV C60 mission accomplished as of SpaDeX spacecraft is considered,” said Mission director M Jayakumar.

Dubbed as a prelude to ISRO setting up its own Space Station by 2035, the PSLV-C60 mission would also make India join an elite club in achieving this feat which is expected to take place in the coming days.

The 44.5 metre tall rocket carried two spacecraft — Spacecraft A and B, each weighing 220kg which would help in space docking, satellite servicing and interplanetary missions.

After the culmination of the 25 hour countdown which commenced on Sunday, the rocket lifted-off at 10 pm from the First Launch Pad at this spaceport, emanating thick orange coloured fumes and thunderous sound in the island, located about 135 km east of Chennai.

According to ISRO scientists, the two spacecraft-Spacecraft A (SDX01) or the ‘Chaser’ and Spacecraft B (SDX02) or the ‘Target’ would be merged together later at an altitude of about 470 km after travelling at the same speed and distance.

By mastering the docking technologies, ISRO is set to enhance its operational flexibility and also expand its mission horizons.

This technology is essential for some of India’s space ambitions like Indian on Moon, getting samples from the Moon (Chandrayaan-4 mission), building and operation of the Bharatiya Antariksh Station.

“In-space docking technology is essential when multiple rocket launches are required to achieve common mission objectives. Through this mission, India is marching towards becoming the fourth country in the world to have space docking technology,” ISRO said.

The others to achieve this technological feat are China, Russia and the US.

While the Spacecraft has reached the desired orbit, in the coming days, scientists would take measures to merge the two by reducing the distance between them, ultimately leading to the docking of the spacecraft.

The launch of PSLV-C60 would be the last mission undertaken by the ISRO in 2024. Incidentally, the space agency began 2024 with the successful launch of PSLV-C58/XPOSAT mission on January 1.

Monday’s PSLV rocket also becomes the first vehicle to be integrated upto the fourth stage at the PSLV Integration Facility (PIF) that has been established at the Satish Dhawan Space Centre.

(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)