"I get lots of phone calls. Quite often people have spotted a planet - often Jupiter and Venus - and they don't realise it. I ask them which direction they were looking at; what time it was and I can go check and see what was up at that time," Dr Nicola Loaring outreach astronomer at the South African Astronomical Observatory told News24.
She said that members of the public often call or send pictures of objects they have photographed and identified as Unidentified Flying Objects.
"There're also the UFOs which people see and sometimes I get photos sent to me and it's quite difficult from the photos to work out what it is," said Loaring.
Orthodox scientists do not recognise that aliens from other worlds or dimensions are regularly visiting Earth, but there are aerial anomalies that have been observed both at night as well as during the day.
Loaring said that some of the photographed anomalies may be errors on recording equipment.
"It could an aircraft; it could be Chinese lanterns. Apparently people confuse them with UFOs and I got one picture once where there was a smudge - a greenish smudge - but that was from the camera. It was a reflection in the lens."
Astronomers have expanded their field to include observations from the public and it has helped identify previously unknown objects.
In 2007, Dutch school teacher Hanny van Arkel discovered a massive gas cloud about 650 million light years away from Earth and around 16 000 light years across.
The object, known as Hanny's voorwerp has become the subject of much research by professional astronomers.
"That [Hanny's voorwerp] was something they weren't aware of and they found this and they got a whole lot of people to carry on in Galaxy Zoo to look for more of them. And they've written papers on it now," Loaring said.
She added that with the wealth of current data available, there wasn't enough researchers to do a proper examination and the public could get involved in early stage analysis.
"That was something they just weren't expecting. There're quite a few citizen science projects out there and people can contribute because there's so much data; there're not enough [professional] people to look at it."
Still, despite the best efforts of researchers, some observations, particularly by credible witnesses such as pilots leave astronomers baffled.
This is especially true when an observation of a UFO cannot be explained by clouds, tricks of light or known aeroplanes.
"Other times you really can't tell what it is. And you're just... 'I don't know'," said Loaring.
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