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

India's Chandrayaan-3 successfully landed on the South Pole of the Moon for the first time in its history on August 23 evening. But, the Chinese scientist Wang Xiaoyuan made an explosive comment on such information. He claimed that India's Chandrayaan-3 did not land on the moon. His comments caused uproar. Criticism and controversy have started.

The country's scientist Wang Xiaoyuan gave this information in an interview with the Chinese language newspaper Science Times. The Indian magazine Business Today gave such news citing Science Times.

Wang Xiaoyuan said the place where the rover landed was at 69 degrees south latitude, not near the South Pole. The South Pole is defined between 88.5 degrees and 90 degrees.

In that interview, he also said that the landing site of Chandrayaan-3 is not at the south pole of the moon and it is not near the south pole of the moon. The information about Moon landing at the South Pole is incorrect, as the distance from the Chandrayaan-3 landing site to the Moon's South Pole region is 619 km.

Xiaoyuan is not the first Chinese scientist to question Chandrayaan-3's achievements.

Earlier, Beijing-based space expert Pang Zhihao told state media Global Times that China is far more advanced in many fields. Since the launch of Chang-2 in 2010, China has been able to send orbiters and landers directly into Earth-Moon transition orbits.

Pang Zhihao also said that the engine used by China is also very advanced. India's lander Pragyan has a lifespan of one lunar day and cannot withstand lunar nights, but China's nuclear-powered UTU-2 rover holds the record for longest operation on the lunar surface.

We all know that 24 hours day and night. After the tiredness of the whole day, we sleep at night, waiting for a new dawn. But think once, where the sun does not set, how will the new dawn come? Or where there is no night, when the people will sleep to remove the tiredness of the day? Do you think there is a place? Not unreal, there are places on earth where the sun never sets. After a long sleep where people do not see the dawn.

In today's discussion, we will know some places in the world, where the sun does not set even at night!

Norway: Norway is called the land of the shining sun. The country's geographical location makes it different from other countries in the world. From May until the end of July, the sun does not set in the Norwegian sky. As a result, Norwegian people do not see the night for two and a half months! Another specialty of the country is that the sun can be seen on the horizon even at night from the port of Hammerfest, Norway, as it is located in the Arctic region.

Nunavut, Canada: The Canadian territory of Nunavut is located 2 degrees above the Arctic Circle. The sun does not set here for about two months of the year. Not only that, the sun cannot be seen for 30 consecutive days in this place during winter. That is, the people here live under the shadow of the sun for two months on the one hand, in the same way they have to live in a long night for a month.

Iceland: Iceland is famous for its absence of snakes and mosquitoes. After Great Britain, Iceland is the largest island in Europe. The sun can be seen in this island even at night in June.

Barrow, Alaska: The sun is visible in the night sky from late May to late July (summer) in this area of Alaska. There is the reverse side of the coin! Not only does the sun never set, there are continuous nights here from early November to early December. That's why this place is also known as 'Polar Nights'.

Finland: Finland is called the land of thousand lakes and islands. The sun does not set for 73 consecutive days during summer in this European country. Similarly, the sun does not appear here for 32 consecutive days in winter. Because of this strange natural disparity, most people in that country believe that people sleep more in winter and less in summer.

Sweden: We all know that 365 days make up a year. But Sweden's year ends in one day! Because half of the year is day here, the other half is night. Even pulled again! So taking the day and night as the sun, it can be said that the year in Sweden is spent in one day! And people here spend half of the year in the dark and the other half in the light.

Diplomatic relations between India and Canada are on the verge of ending over the death of Indian pro-Khalistan leader Hardeep Singh Nijjar. Both countries have expelled each other's diplomats.

In this situation, the New York Times report claimed that the United States had provided information to Canada about the killing of Nijjar. Through that information, Canada found India's link in Nijjar's murder.

The New York Times report, quoting an official from the 'Five Eyes Partners', an alliance of intelligence agencies from the US, Britain, Australia, Canada and New Zealand, claimed that US intelligence provided information to Canada immediately after the assassination. However, at that time the US was not aware of the possibility of India's involvement in the killings.

Meanwhile, Trudeau claimed on Saturday that Canada had sent information to New Delhi about the killing of Nijjar a few weeks ago. However, India said that Canada could not provide India with any evidence against the information.

On the other hand, Canadian intelligence claimed that Nijjar was a cleric. In response, New Delhi said Nijjar was not a religious guru, but a murderer.

According to India, Nijjar became the head of the Gurdwara by scaring his brother Raghbir.

Hindustan Times reported that pro-Khalistan leader Hardeep Singh Nijjar was shot dead inside the Gurdwara on June 18. Hardeep was shot more than 20 times.

According to reports, Nijjar lived in the Punjabi-dominated Sari region of British Columbia, Canada. Hardeep was behind the Khalistani protests in front of the Indian High Commission in Vancouver, Canada in the past few years.

The Russian government has allowed the country's banks and financial institutions to transact in Russian currency.

This information was reported on the official Facebook page of the Russian Embassy in Bangladesh on Saturday (September 23).

According to the information given on the Facebook page, Russia has allowed 30 other countries to trade in ruble currency except Bangladesh. The countries are - Armenia, Azerbaijan, Belarus, Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, Uzbekistan, Algeria and Bahrain.

Also included are Brazil, China, Cuba, Egypt, India, Indonesia, Iran, Qatar, Malaysia, Mongolia, Morocco, Oman and Pakistan.

Saudi Arabia, Serbia, South Korea, Turkey, United Arab Emirates, Venezuela and Vietnam are also allowed to trade in ruble. However, Argentina, Hong Kong, Israel, Mexico and Moldova have been excluded from the list.

Recently, before Russian Foreign Minister Sergey Lavrov's visit to Dhaka, Bangladesh Foreign Minister AK Abdul Momen said that the discussions on commercial transactions in the country's single currency have been going on for quite some time.