Aliens may have Existed On Earth. Here�s Why They Left

It�s one of humanity�s most all-consuming questions, fascinating scientists, governments and pop culture alike.  But now, one US space scientist is claiming that advanced life forms may be a reality � but that they disappeared long ago.

Professor Jason Wright, an astronomy and astrophysics professor at Pennsylvania State University, published a paper in arXiv entitled �Prior Indigenous Technological Species�.

He claims that ancient �technological species� may have lived on Earth billions of years before the human race. Well, either Earth, or a �pre-greenhouse Venus,� or �a wet Mars�. He�s not 100 per cent sure.

However, Wright claims:

Given that it is known to host complex life, the most obvious origin for a prior species of any sort is Earth.

He pulls no punches when he explains that:

Present-day Venus would seem to be a terrible candidate for a technological species, with a surface temperature over 700K, although when it comes to alien life we should keep an open mind about even this.

Wright believes that the ancient species has disappeared, but that in the past we could have found found traces of them underground, called �technosignatures�.  However, he claims that most of the physical evidence would now be lost.

On Venus, for example, the global greenhouse arrival may have resulted in a resurfacing of the planet, while on Earth the movement of tectonic plates and subsequent erosion could have erased any lingering traces. Nevertheless, he writes, it might still be possible to recognise these technosignatures even if the physical evidence is all but destroyed.

He explains:

Structures buried beneath surfaces might survive and be discoverable as long as they do not suffer a collision so severe that their artificial nature is obliterated. Merely destroying them would render them nonfunctional, but they might still be recognisably technological. We might conjecture that settlements or bases on these objects would have been built beneath the surface for a variety of reasons, and so still be discoverable today.

He claims that ancient �technological species� may have lived on Earth billions of years before the human race. Well, either Earth, or a �pre-greenhouse Venus,� or �a wet Mars�. He�s not 100 per cent sure.

However, Wright claims:

Given that it is known to host complex life, the most obvious origin for a prior species of any sort is Earth.

He pulls no punches when he explains that:

Present-day Venus would seem to be a terrible candidate for a technological species, with a surface temperature over 700K, although when it comes to alien life we should keep an open mind about even this.

Wright believes that the ancient species has disappeared, but that in the past we could have found found traces of them underground, called �technosignatures�.  However, he claims that most of the physical evidence would now be lost.

On Venus, for example, the global greenhouse arrival may have resulted in a resurfacing of the planet, while on Earth the movement of tectonic plates and subsequent erosion could have erased any lingering traces. Nevertheless, he writes, it might still be possible to recognise these technosignatures even if the physical evidence is all but destroyed.

He explains:

Structures buried beneath surfaces might survive and be discoverable as long as they do not suffer a collision so severe that their artificial nature is obliterated. Merely destroying them would render them nonfunctional, but they might still be recognisably technological. We might conjecture that settlements or bases on these objects would have been built beneath the surface for a variety of reasons, and so still be discoverable today.