Australia's first female astronaut Katherine Bennell-Pegg believes there are "definitely aliens out there".
Katherine Bennell-Pegg believes that aliens exist
The 39-year-old scientist - who is the Director of Space Technology with the Australian Space Agency (ASA) - says the data and statistics point to the existence of extra-terrestrial lifeforms.
Speaking at Sydney's South by Southwest conference, she said: "There are definitely aliens out there. I don’t think they walk among us, even if it feels like that sometimes.
"Given the scale of the universe, we think there are somewhere between 100 to 200 sextillion stars in the universe.
"That is similar to the number of grains of sand on all the beaches on Earth.
Katherine says "6,000 exoplanets" have been discovered in the past six years, with many of them having the capability to support life.
She added: "We’ve just started looking at exoplanets with space telescopes, and just in the last six years we’ve found almost 6,000 exoplanets, that is planets around other stars.
"Many of them are in what could be a habitable zone.
"I just think, odds are, life is out there. The interesting thing is though, if it is, will we ever be able to communicate with them? Who knows?"