Despite some conspiracy theories claiming that the Earth is flat, many scientific research and mathematical calculations have reached the same result: our planet is spherical. Satellite records also prove this. But what would the shape of the Universe be?
In this case, the answers are a little more complicated.
If the Greek philosophers already pointed to the possibility of the Earth being spherical — which can be proved by the first photograph taken from space in 1972 — until the beginning of the 2000s, there were three main theories regarding the shape of the Universe:
- closed (like the surface of a ball)
- open (like a horse’s saddle)
The doubt existed because from Earth we were not able to make complete records of the Universe. It was then necessary to wait for the launch of specialized satellites, to be able to make new observations and find the answers.
In 2001, NASA (the United States space agency) sent the WMAP mission into space. And in late 2012, she presented her results. One of the most important is that the researchers were able to calculate the curvature of the Universe: 0.4%. In other words, the Universe would be flat.
“In the past, we knew less about the Universe, so there were several theories”, says Thaisa Storchi-Bergmann, astrophysicist and professor at the Institute of Physics at UFRGS (Federal University of Rio Grande do Sul).
“Today we know that, if it were very curved, we could observe an object at different times, which does not happen”, says the researcher, who is a member of the Brazilian Academy of Sciences.
“What we know is that, if the Universe was born flat, it will remain flat. And the most accepted model is from scientists who have shown that it behaves according to Einstein’s equations”, adds the professor.
If the most accepted theory today is that the universe is flat, its exact shape still doesn’t have an answer. And there is no known limit, because there is a Universe beyond what we can see, highlights a researcher from UFRGS.
Measuring shape is difficult because, since the Big Bang, which happened almost 14 billion years ago, the Universe has been expanding. Therefore, its distance is estimated to be approximately 46 billion light-years.
Another enigma that worries scientists is the composition of the Universe.
According to the WMAP mapping, 71.4% of it is made up of dark energy, 24% of dark matter and 4.6% of atoms. As scientists only know how the latter behave, 95% of the Universe remains a great mystery.
*With text by Marcelle Souza and updated article published in 2018.