Johannesburg - Imagine how difficult it would be to find a needle in a haystack, if you had to find the haystack itself first.
This is the comparison made by an astronomer when asked if South Africans could see a star orbited by what could potentially be the nearest “Earth-like” planet .
Gliese 832c is an exoplanet – a planet which orbits a star other than the Sun – which was discovered just more than three weeks ago by a team from the University of New South Wales, Australia, led by Robert Wittenmyer.
The team based their findings on 15 years of data from three telescopes and said the exoplanet fell within the “habitable zone”, called the Goldilocks zone because the distance between the exoplanet and its star is “just right” to theoretically support surface water.
Gliese 832c has given a relatively high rating of 0.81 on the Earth Similarity Index (ESI), which runs from 0 to 1.
This makes it the third highest ESI rated exoplanet to date, but is the closest of the three to Earth, according to the Planetary Habitability Laboratory at the University of Puerto Rico.
“So far, the two planets of Gliese 832 (the star) are a scaled-down version of our own solar system, with an inner potentially Earth-like planet and an outer Jupiter-like giant planet,” the Planetary Habitability Laboratory said.
“However, given the large mass of the planet, it seems likely that it would possess a massive atmosphere, which may well render the planet inhospitable,” said Wittenmyer’s research.
According to Gary Els, chairman of the Astronomical Society of Southern Africa’s Joburg centre, the potential of surface water on Gliese 832c was “pure speculation”.
He said South African stargazers would need a “serious” telescope – one with at least a 25cm diameter – to catch a glimpse of the exoplanet’s star.
“Even then it would just be like looking at one of our bright stars with the naked eye,” he said.
Keen astronomers could point their telescopes at the south-eastern horizon from about 7pm until sunrise in the hope of spotting it, said Kenny Nevill, chairman of the West Rand Astronomy Club.
But if Gliese 832c is unreachable at 16 light years away from Earth, why is there so much interest in it?
“It’s all about trying to find life, where we come from and where we can go.”
The Star