Aditya-L1 successfully completes fourth earth-bound manoeuvre: ISRO



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Aditya L1 spacecraft, India's first space-based mission to study the Sun, during the early hours on Friday, underwent the fourth earth-bound manoeuvre successfully, ISRO said.

"The fourth Earth-bound manoeuvre (EBN#4) is performed successfully. ISRO's ground stations at Mauritius, Bengaluru, SDSC-SHAR and Port Blair tracked the satellite during this operation, while a transportable terminal currently stationed in the Fiji islands for Aditya-L1 will support post-burn operations," the space agency said in a post on X, a platform formerly known as Twitter.

The new orbit attained is 256 km x 121973 km, it said: "The next manoeuvre Trans-Lagragean Point 1 Insertion (TL1I) -- a send-off from the Earth -- is scheduled for September 19, around 02:00 Hrs. IST."

Aditya-L1 is the first Indian space-based observatory to study the Sun from a halo orbit around the first Sun-Earth Lagrangian point (L1), which is located roughly 1.5 million km from the Earth.

The first, second and third earth-bound manoeuvre was successfully performed on September 3, 5 and 10 respectively.

The manoeuvres are being performed during the spacecraft's 16-day journey around the Earth during which the spacecraft will gain the necessary velocity for its further journey to L1.

With the completion of four earth-bound orbital manoeuvres, Aditya-L1 will next undergo a Trans-Lagrangian1 insertion manoeuvre, marking the beginning of its nearly 110-day trajectory to the destination around the L1 Lagrange point.

Upon arrival at the L1 point, another manoeuvre binds Aditya L1 to an orbit around L1, a balanced gravitational location between the Earth and the Sun.

The satellite spends its whole mission life orbiting around L1 in an irregularly shaped orbit in a plane roughly perpendicular to the line joining the Earth and the Sun.

ISRO's Polar Satellite Launch Vehicle (PSLV-C57) on September 2 successfully launched the Aditya-L1 spacecraft from the Second Launch Pad of Satish Dhawan Space Centre (SDSC), Sriharikota.

After a flight duration of 63 minutes and 20 seconds that day, the Aditya-L1 spacecraft was successfully injected into an elliptical orbit of 235x19500 km around the Earth.

According to ISRO, a spacecraft placed in the halo orbit around the L1 point has the major advantage of continuously viewing the Sun without any occultation /eclipses.

This will provide a greater advantage in observing solar activities and their effect on space weather in real-time.

Aditya-L1 carries seven scientific payloads indigenously developed by ISRO and national research laboratories, including the Indian Institute of Astrophysics (IIA) in Bengaluru and the Inter-University Centre for Astronomy and Astrophysics (IUCAA) in Pune.

The payloads are to observe the photosphere, chromosphere and the outermost layers of the Sun (the corona) using electromagnetic particle and magnetic field detectors.

Using the special vantage point L1, four payloads directly view the Sun and the remaining three payloads carry out in-situ studies of particles and fields at the Lagrange point L1, thus providing important scientific studies of the propagatory effect of solar dynamics in the interplanetary medium.

The suits of Aditya L1 payloads are expected to provide the most crucial information to understand the problem of coronal heating, coronal mass ejection, pre-flare and flare activities and their characteristics, dynamics of space weather, and propagation of particles and fields.

According to scientists, there are five Lagrangian points (or parking areas) between the Earth and the Sun where a small object tends to stay if put there. The Lagrange Points are named after Italian-French mathematician Joseph-Louis Lagrange for his prize-winning paper -- "Essai sur le Probleme des Trois Corps, 1772."

These points in space can be used by spacecraft to remain there with reduced fuel consumption.

At a Lagrange point, the gravitational pull of the two large bodies (the Sun and the Earth) equals the necessary centripetal force required for a small object to move with them.

Source: Hindustan Times

 

   

Israel launched a ground attack in Rafah amid ceasefire talks



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Israel launched a ground attack in Rafah in the midst of Israel-Hamas ceasefire talks in Gaza.

A delegation from the Palestinian group Hamas is in the Egyptian capital for ceasefire and prisoner-release talks. Sources said Ceasefire talks have progressed.

International media Al Jazeera reported in a report that despite the negotiations, Israel continued its ground attack on Rafah, the southernmost city of Gaza.

A Hamas delegation arrived in Cairo on Saturday to meet with mediators from Qatar, Egypt and the United States to negotiate a 40-day ceasefire, according to reports published by the United Kingdom.

The talks are at a critical stage, sources told Al Jazeera, as a Qatari technical team is working out the details of a potential deal with the Egyptians.

As technical teams indicate, we are moving into the operational side of a deal. They are monitoring the issues in detail in this agreement.

A senior Hamas spokesman, Osama Hamdan, told Al Jazeera, "It is clear that we are moving forward. There are some good points.

"So far we are still talking about the main issue, which is a complete ceasefire and a complete withdrawal from Gaza," he said. We hope to find some good and positive answers today.

Israel said it will continue to attack Rafah despite talk of a possible deal with Hamas. UN agencies and aid groups have long warned that the ground operation would spell disaster for the 15 lakh people taking refuge there.

Hamdan said, "Unfortunately, Netanyahu has made a clear statement that no matter what happens, if there is a ceasefire or not, he will continue to attack." That means there will be no ceasefire, and that means that the offensive will continue.

Al Jazeera's Ahlbara said the talks were focused on convincing Hamas that it should refrain from demanding a permanent ceasefire from Israel during the first phase of the deal because it is unlikely to happen.

On October 7, Hamas fighters attacked southern Israel, killing more than 1,100 people. During this time, more than 240 people were captured by Hamas.

Later, more than 34,600 Palestinians have died in Israel's attack on Gaza. More than 70 percent of Palestinian territory has been reduced to rubble, pushing the region toward famine.

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Attacks on environmental journalists are on the rise worldwide: UN



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According to a recently published report by the United Nations Educational, Scientific and Cultural Organization UNESCO, 44 environmental journalists from 15 countries around the world lost their lives in violent attacks from 2009 to 2023; And 24 people managed to return alive.

This information was reported in the report of the news agency Reuters on Friday (May 3).

According to the report, attacks on environmental journalists are increasing around the world. UNESCO representatives interviewed 905 environmental journalists from 129 countries to prepare the report.

In the interview, 749 out of 905 journalists (more than 70 percent) said that they had to face physical attacks or intimidation, threats, and pressure at some point in their lives to perform their professional duties. Many have also had to deal with the legal problems of detention and defamation cases.

Analyzing the cases of assault-harassment, it has been found that the cases of physical assault have occurred more among male journalists. On the other hand, women journalists are more victims of harassment.

Journalists have been attacked and harassed while reporting on various environmental issues. These issues include various mining irregularities, land tenure conflicts, deforestation, extreme weather related disasters, pollution and environmental damage, fossil fuel sector and its trade etc.

All of these attacks and harassment have come from individuals and groups associated with the power structure of the state. In this context, the UNESCO report said, 'Police, army, government officials and employees, people of local government authorities are responsible for these attacks and harassment. 

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Russia is using banned chemical weapons in Ukraine: US



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Dhaka: US accuses Russia of using 'Chloropicrin', a banned chemical used in World War I, in Ukraine.

On Thursday (May 2), the British media BBC reported that US State Department officials said that the attack on Ukraine with this weapon is not an "isolated" incident. Russia often uses it.

However, the Kremlin rejected the allegations, saying the US allegations were baseless. Kremlin spokesman Dmitry Peskov told reporters in Moscow that Russia maintains its obligations under the Chemical Weapons Convention (CWC).

According to the CWC, the use of ‘chloropicrin’ in any war is strictly prohibited. According to the US Centers for Disease Control and Prevention (CDC), the use of this chemical in oil can cause inflammation of the lungs, eyes and skin of people. It can also cause vomiting, nausea and diarrhea.

According to the US, Russia has used chloropicrin to force Ukrainian troops to retreat from fortified positions.

US President Joe Biden had earlier warned Russia about the use of chemical weapons in Ukraine. He warned in March 2022, weeks after the attack on Ukraine, that if Russian President Vladimir Putin authorized the use of chemical weapons, he would pay a "heavy price".

However, Moscow has been repeatedly accused of using chemical weapons in Ukraine. Mallory Stewart, US Assistant Secretary of State for Arms Control has accused Russia of using riot control chemicals. Ukrainian soldiers have also reported being subjected to chemical attacks in recent months.

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Turkey stopped trade with Israel over the Gaza issue



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Turkey has stopped all trade with the illegal occupier Israel due to the Gaza war.

The British media BBC reported on Thursday (May 2) about the Turkish Ministry of Commerce.

The trade embargo will remain in effect until Israel allows uninterrupted and adequate humanitarian aid to Gaza, the Turkish trade ministry said.

According to the BBC, the trade between Israel and Turkey is about 7 billion US dollars in 2023.

Israel's foreign minister accused Turkish President Recep Tayyip Erdogan of treating him like a dictator in announcing the trade freeze.

Israeli Foreign Minister Israel Katz wrote on social media that Erdogan is violating international trade agreements by ignoring the interests of the Turkish people and businessmen.

Israel's foreign minister has instructed government agencies to import goods from other countries and produce goods locally as an alternative to Turkey's trade freeze.

He wrote, I have directed the IMF Director General to immediately start working with the concerned parties to find trade options with Turkey. I also asked him for local production and import of products from other countries. Israel will emerge as a powerful and formidable economy. They lose we win.

In 1949, Turkey was the first Muslim-majority country to recognize Israel. But relations between the two countries have deteriorated in recent times.

In 2010, Turkey cut diplomatic ties with Israel after ten pro-Palestinian Turkish activists were killed in clashes with Israeli commandos.

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