K Sivan said that while they were trying to establish contact with 'Vikram', the orbiter's life had increased to 7.5 years due to the optimal mission operation though its designed life was one year.
Sivan said that ISRO is focusing on another moon mission by 2020 for which discussion is on without nothing being finalised.
The nation waited with bated breath as Chandrayaan-II entered the moon’s orbit. For a couple of days everything else was pushed off centrestage.
So far, the national space agency has been tight-lipped about what caused the last-minute glitch which denied India the credit of becoming the fourth nation to soft-land on the moon's surface.
Sivan did not mention where exactly the Vikram lander was located, but an ISRO scientist said it 'was just a few meters away from the intended landing site'.
"Known for his hard work, honesty, straightforwardness and self-confidence, he will take this as a challenge rather than a failure," said A Shanmugavel, 80.
ISRO officials strongly fell that India's first moon lander Vikram crash on to the lunar surface resulting in the sudden snapping of the communication link.
PM Narendra Modi's address comes after ISRO lost communication with 'Vikram' lander of Chandrayaan 2 moments before it was preparing to make a soft-landing on the south pole region of the Moon.
First set of pictures of Moon taken by Chandrayaan-2's LI4 Camera from an altitude of about 2,650 km from the lunar surface released by ISRO on August 22.
The Prime Minister will address the nation at around 8 am, according to ISRO.
Trying to uplift the mood and boost the anxious scientists' morale, Modi, with a smile, said: "From my side I congratulate all of you."
When the top ISRO scientists including its chief Sivan looked glum soon after the subsequent fine braking phase commenced, it was the first indication that all was not well.
The touch-down of 'Vikram' lander is scheduled between 1.30 am and 2.30 am on Saturday, followed by the rollout of rover 'Pragyan' between 5.30 a.m and 6.30 a.m.
From now and until touchdown, ISRO Chairman K Sivan had said, that scientists will check parameters of the lander to ensure the system is perfect.
The scientist said today every moment of our life was one way or other connected with space technology.