The Indian space agency lost contact with its lunar probe on Saturday, just before it was due to land near the south pole of the moon.
There has been no official statement released on the status of the Chandrayaan-2 mission. India launched the mission on July 22 in a bid to become the fourth country, after the US, Russia and China, to successfully land on the moon.
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"The Vikram lander descent was going as planned and normal performance was observed," Indian Space Research Organisation (ISRO) Chairman Kailasavadivoo Sivan said in the mission control room.
"Subsequently the communication from lander to ground station was lost. The data is being analyzed," he said.
The ISRO said in a Tweet that normal performance was observed in the lander up to an altitude of 2.1 kilometers (1.3 miles) from the lunar surface.
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An ISRO official told the Indo-Asian News Agency (IANS) on condition of anonymity that it was too early to determine the fate of the spacecraft. "Only 5% of the mission has been lost -- Vikram the lander, and Pragyan the rover, while the remaining 95% -- that is the Chandrayaan-2 orbiter -- is still orbiting the moon successfully."
The orbiter can take pictures of the lander to know its status, the official added.
Indian Prime Minister Narendra Modi, who was at ISRO's Bangalore space center to watch the landing, said after Sivan's announcement that what the scientists had already accomplished was "not a small achievement."
"Ups and downs keep coming in life. Your hard work has taught us a lot and the entire country is proud of you," said Modi. "If the communication starts again ... hope for the best ... Our journey will carry on."
After giving a speech at the ISRO on Saturday, Modi was seen consoling an emotional Sivan.
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The lander was due to touch down around 1:55 a.m. New Delhi time (2025 UTC). Mission leader Sivan had said before the landing that it was very complex, calling it "15 minutes of terror."
India's previous moon mission, Chandrayaan-1, involved an impact probe that intentionally "crashed" on the lunar surface in 2008. At the time, ISRO said the intentional crash near the lunar south pole was a success, as it confirmed the presence of water molecules on the moon's surface.
The Chandrayaan-2 mission, aimed at studying shadowed craters thought to contain water deposits, is estimated to have cost $140 million (€125 million).
shs, wmr/sms (AFP, Reuters, AP)
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