ISRO successfully carries out controlled re-entry experiment of aged satellite
Bengaluru (PTI): The Indian Space Research Organisation said it successfully carried out an "extremely challenging" controlled re-entry experiment of the decommissioned orbiting Megha-Tropiques-1 (MT-1) satellite.
"The satellite re-entered the Earth's atmosphere and would have disintegrated over the Pacific Ocean", the Bengaluru-headquartered national space agency said on Twitter on Tuesday.
The final impact region estimated is in the deep Pacific Ocean within the expected latitude and longitude boundaries, an ISRO statement said.
The low Earth satellite was launched on October 12, 2011, as a joint satellite venture of ISRO and the French space agency, CNES for tropical weather and climate studies.
Since August 2022, the satellite's perigee was progressively lowered through a series of 20 manoeuvres, spending about 120 kg of fuel.
Multiple manoeuvres including the final de-boost strategy were designed after taking into consideration several constraints, including visibility of the re-entry trace over ground stations, ground impact within the targeted zone, and allowable operating conditions of subsystems, especially the maximum deliverable thrust and the maximum firing duration constraint on thrusters.
All manoeuvre plans were screened to ensure that there would be no post manoeuvre close approaches with other space objects, especially with the crewed space stations like International Space Stations and the Chinese Space Station, ISRO said.
The final two de-boost burns were executed at 11:02 UTC and 12:51 UTC respectively on March 7 by firing four 11 Newton thrusters on-board the satellite for about 20 minutes each, it said.
The final perigee was estimated to be less than 80 km, indicating that the satellite would enter the denser layers of the Earth's atmosphere and subsequently undergo structural disintegration. The re-entry aero-thermal flux analysis confirmed that there would be no surviving large debris fragments.
The entire sequence of events was carried out from the Mission Operations Complex in ISTRAC (ISRO Telemetry, Tracking and Command Network), Bengaluru.
An uninhabited area in the Pacific Ocean between 5 S to 14 S latitude and 119 W to 100 W longitude was identified as the targeted re-entry zone for MT1, weighing about 1000 kg, ISRO said earlier this week.
About 125 kg on-board fuel remained unutilised at its end-of-mission that could pose risks for accidental break-up, an ISRO statement had noted.
This left-over fuel was estimated to be sufficient to achieve a fully controlled atmospheric re-entry to impact the uninhabited location in the Pacific Ocean, ISRO had said.
Controlled re-entries involve de-orbiting to very low altitudes to ensure impact occurs within a targeted safe zone.
Usually, large satellites/ rocket bodies, which are likely to survive aero-thermal fragmentation upon re-entry, are made to undergo controlled re-entry to limit ground casualty risk.
However, all such satellites are specifically designed to undergo controlled re-entry at end-of-life (EOL).
"MT-1 was not designed for EOL operations through controlled re-entry which made the entire exercise extremely challenging," ISRO said.
Furthermore, the on-board constraints of the aged satellite, where several systems had lost redundancy and showed degraded performance, and maintaining sub-systems under harsher environmental conditions at much lower than originally designed orbital altitude added to the operational complexities, it said.
Innovative workarounds were implemented by the operations team based on the study, deliberations, and exchanges among the mission, operations, flight dynamics, aerodynamics, propulsion, controls, navigation, thermal, and other sub-system design teams across the ISRO centres, who worked in synergy to surmount these challenges, it said.
Although the mission life of the satellite originally was three years, it continued to provide valuable data services for more than a decade supporting regional and global climate models till 2021, ISRO said.
UN/IADC (Inter-Agency Space Debris Coordination Committee) space debris mitigation guidelines recommend de-orbiting a LEO (Low Earth Orbit) object at its EOL, preferably through controlled re-entry to a safe impact zone, or by bringing it to an orbit where the orbital lifetime is less than 25 years, according to ISRO.
It is also recommended to carry out "passivation' of on-board energy sources to minimise the risk of any post-mission accidental break-up, ISRO said.
The orbital lifetime of MT-1 would have been more than 100 years in its 20 deg inclined operational orbit of 867 km altitude, it said.
"As a responsible space agency committed to safe and sustainable operations in outer space, ISRO proactively takes efforts for better compliance with the UN/IADC space debris mitigation guidelines on post-mission disposal of LEO objects", the ISRO statement said.
Let the Truth be known. If you read VB and like VB, please be a VB Supporter and Help us deliver the Truth to one and all.
Not UN’s role to regulate AI, says Guterres as world body plans annual global dialogue
United Nations (PTI): It is not the UN’s role to regulate AI, Secretary General Antonio Guterres has emphasised as he pointed to an annual global dialogue being planned at the international organisation on AI with participation from all countries, governments, private sector as well as civil society.
Guterres will soon be arriving in New Delhi to attend the India AI Impact Summit, the first-ever summit on Artificial Intelligence hosted in the Global South.
In an exclusive interview to PTI ahead of his visit to India for the Summit, Guterres outlined efforts by the international organisation aimed at global cooperation on Artificial Intelligence (AI), emphasising that these are “perfectly in line” with the strategy demonstrated by India in its leadership of the AI summit.
Guterres highlighted three key areas under the Global Digital Compact initiated at the UN to contribute towards the global AI architecture.
ALSO READ: Modi invites Bangladesh PM to visit India, says looking forward to working closely
The first is the creation of a new high-level Independent International Scientific Panel on Artificial Intelligence comprising 40 experts from around the world.
The UN General Assembly last week appointed the 40 members recommended by Guterres to the independent panel.
Head of the Department of Data Science and Artificial Intelligence (DSAI) at IIT Madras Balaraman Ravindran is among the global group of 40 distinguished experts recommended by Guterres to serve on the panel for a three-year term from date of appointment.
Guterres said that through the panel, “We will have a totally independent and universal…scientific body (that will be) able to tell the world at each moment where are we in relation to AI? What are the advances that were made? What are the discoveries that were established? What are the risks of (various) mechanisms or instruments, and to do it in a totally independent way.”
He described this as a “fantastic source” of information for governments to take the right decisions in policies and measures in relation to AI and “for the people at large to know public opinions, in democratic countries like India that is very important.”
Guterres also pointed to an annual global dialogue being planned at the UN on AI with participation from all countries, governments, private sector as well as civil society.
Emphasising that it is not the UN’s role to regulate AI, Guterres said the global dialogue will be a “platform where everybody can come and everybody can discuss, and where we can learn with each other and eventually come to some possible consensus on the best way to maximise the opportunities of AI and minimise its risks.”
Lastly, he expressed hope that his proposal of a fund will be approved.
“There was an agreement in the General Assembly in order to support developing countries to build capacity to be able to benefit from AI. So these are three very important contributions of the UN and I believe that these contributions are perfectly in line with the strategy that India has demonstrated in the leadership in the preparation of the present Summit,” he said.
The UN chief has proposed a voluntary global fund of up to three billion dollars to support countries in the field of AI capacity building.
The Global Digital Compact, adopted at the 2024 Summit of the Future, had set out a shared vision for an open, safe and inclusive digital future.
Among its commitments was the creation of an Independent International Scientific Panel on AI to advance scientific understanding and ensure that international deliberations are informed by the best available evidence, the UN has said.
Stéphane Dujarric, Spokesperson for the Secretary-General, told reporters that Guterres is scheduled to participate in the Summit’s opening ceremony, a plenary with heads of state and government, as well as a session on the role of science in international AI governance.
The Secretary-General will have bilateral meetings with President Droupadi Murmu, Prime Minister Narendra Modi and will also meet with other global and tech leaders attending the Summit, as well as members of the International Scientific Panel on Artificial Intelligence.
While in India, Guterres is also scheduled to take part in a roundtable organised by the UN to discuss renewable energy and energy transition.
"With India emerging as a global leader in renewable energy expansion, the discussion will bring together senior figures from industry, finance, policy and civil society to identify concrete steps to further accelerate renewable energy deployment, strengthen grids and storage, and mobilise investment at scale.
“This engagement is part of the Secretary-General’s continued efforts to advance a faster, fairer and more inclusive global energy transition, aligned with the Paris Agreement,” Dujarric said.
United Nations India said in a statement that over 30 events organised by the UN system are scheduled during the five-day summit, and will include sessions on AI for resilient agriculture, health systems innovation, ethical AI governance, women’s leadership in technology, digital capacity-building in the Global South and responsible business practices.
The statement by the UN in India said that discussions will focus on “how AI can accelerate progress towards the Sustainable Development Goals while safeguarding human rights and addressing emerging risks”.
At the Summit, Guterres will be joined by senior UN leaders, including UN High Commissioner for Human Rights Volker Türk; Under-Secretary-General and UN Secretary-General’s Envoy on Technology Amandeep Singh Gill and Special Representative of the Secretary-General for Disaster Risk Reduction Kamal Kishore.
Also participating are Managing Director of the International Monetary Fund Kristalina Georgieva; Director-General of the International Labour Organisation Gilbert Houngbo and Secretary-General of the International Telecommunication Union Doreen Bogdan-Martin.
