The Bush administration continued to hail Indian American astronaut Kalpana Chawla who died along with six other crew members when space shuttle Columbia exploded 16 minutes from landing, calling her a "role model" to millions of people both in the United States and India.

One day after President George W Bush described Chawla as "a brave and courageous star born in your great country" during a telephone conversation with Prime Minister Atal Bihari Vajpayee on Sunday, White House spokesman Ari Fleischer said Chawla -- a naturalised US citizen born in India -- besides being a "hero in India" was "an example and a role model to millions in both countries, particularly women".

Fleischer also noted that NASA Administrator Sean O'Keefe who met with President Bush Monday began the 45 minute meeting "by talking about the families of those who lost their lives, the relatives and their well-being now and the care that is being taken for them".

Fleischer said the US president, who is scheduled to meet them on Tuesday at the Johnson Space Centre in Houston before the public memorial ceremony, had "agreed that has to be a priority, to make certain the families are taken care of".

"Mr O'Keefe reviewed the chronology of events that immediately led up to the disaster and he said his intention is to get back into space as soon as possible, with all safety issues having been fully explored," the spokesman said.

Fleischer said the US president had "inquired about the health and status of the families. He talked and inquired about the morale of NASA. We have received no reports of anybody who was hurt by falling debris. Both the president and Mr O'Keefe expressed amazement at that. And obviously, that's one small positive piece of news in this tragedy".

He said the US president had also talked about the status and morale of the next crew "and how they are ready to go as soon as they are able to go back into space", and had also inquired "about the children's experiment that was aboard the space shuttle".

"And finally, the president said to the head of NASA, 'You make us proud'," Fleischer recounted.

Fleischer said O'Keefe had also assured Bush "that all causes of the shuttle explosion will be evaluated, all causes".

He said, "It is vital; this country owes it to the people who lost their lives, to the families left behind, and to the astronauts who lie ready and waiting to go on their next mission to explore every possible reason why this could have happened."

Asked if there is a need or if the president believes it's time to look at accelerating the search for a new generation of space planes to replace the shuttle, given the age of the fleet which with the loss of Columbia has lost a quarter of its strength, Fleischer said just two days after the explosion he was not going to "leap to any conclusions for anybody in the government about what the next steps should be".

He said, "It's important to allow the independent panel and the internal NASA panel to conduct their investigations. Let's find out what the cause of the accident was before reaching conclusions about what the next course in space exploration should be."

"But the principal point I want to emphasise," Fleischer added, "is the president is determined to continue mankind's exploration of space".

The Columbia Crash: The Complete Coverage