Did scientists find a "dimensional gateway" in Antarctica? No, that's not true: The evidence of the portals are computer-generated imagery, or CGI. Multiple photos used as background for these "dimensional gateway" photos are from stock image websites. There is no evidence from credible news outlets that scientists have found a dimensional gateway in Antarctica.
The claim appeared in an article (archived here) published on the website Ancient on April 5, 2023, under the title "Scientific Expedition Finds a Dimensional Gateway in Antarctica -- Sent a Probe Inside the Stargate." It opened:
A number of scientists who were in Antarctica for a climate experiment experienced a never-before-seen occurrence. The researchers studied the ice and the atmosphere after an odd vortex formed over them.
This is what the article looked like at the time of writing:
(Source: Ancient.binodon24live.com screenshot taken Wed Apr 19 15:37:28 2023 UTC)
According to the article, scientists who visited Antarctica witnessed a vortex and a whirlwind. It discusses other locations on Earth that hold portals, like Egypt, Bolivia, Sri Lanka, England and Peru. The article does not cite any sources that would back up this claim. A scientist named Qatar Mamani is quoted, but Lead Stories could not find a scientist with that name (example of the search here).
Below is the first picture seen in the article. The vortex in the foreground has been added to a stock image background. Here is the evidence that the background is a stock image.
(Source: Ancient.binodon24live.com screenshot taken on Wed Apr 19 16:28:49 2023 UTC)
The third picture from the bottom featured in the article is also from a stock image website. Below is that photo from the article. An image of a portal has been added to the photo in the upper-right corner. Here is the evidence that the background is a stock image.
(Source: Ancient.binodon24live.com screenshot taken on Wed Apr 19 17:13:20 2023 UTC)
There are no credible reports of a dimensional gateway being found in Antarctica.
The origins of the two videos seen in the article could not be found using reverse image search engines (example of searches here and here).
Other Lead Stories articles on Antarctica can be found here.
