If intelligent aliens visit the Earth, it would be one of the most profound events in human history.
That percentage has been increasing.
Scientists dismiss these beliefs as not representing real physical phenomena.
They dont deny the existence of intelligent aliens.
But they set a high bar for proof that weve been visited by creatures from another star system.
AsCarl Sagan said, Extraordinary claims require extraordinary evidence.
Most UFO sightings have been in the United States.
Im aprofessor of astronomywho has written extensively on thesearch for lifein the universe.
I also teach afree online class on astrobiology.
Full disclosure: I have not personally seen a UFO.
It’s free, every week, in your inbox.
UFO means unidentified flying object.
Nothing more, nothing less.
Theres a long history of UFO sightings.Air Force studies of UFOshave been going on since the 1940s.
In the United States, ground zero for UFOs occurred in 1947 in Roswell, New Mexico.
The majority of UFOs appear to people in the United States.
Most UFOs have mundane explanations.Over half can be attributedto meteors, fireballs, and the planet Venus.
Such bright objects are familiar to astronomers but are often not recognized by members of the public.
Reports of visits from UFOs inexplicablypeaked about six years ago.
Many people who say they have seen UFOs are eitherdog walkers or smokers.
Are we alone?
Astronomers have discoveredover 4,000 exoplanets, or planets orbiting other stars, a number that doubles every two years.
The nearest of these habitable planets areless than 20 light years away, in our cosmic back yard.
Extrapolating from these results leads to a projection of300 million habitable worldsin our galaxy.
Astronomers are very confident there is life beyond the Earth.
Astronomers use theDrake Equationto estimate the number of technological alien civilizations in our galaxy.
This confidence has fueled an activesearch for intelligent life, which has been unsuccessful so far.
So researchers have recast the question Are we alone?
to Where are they?
The absence of evidence for intelligent aliens is called theFermi Paradox.
Scientists do not discount the idea of aliens.
To my mind, UFOs have become a kind ofnew American religion.
If you believe in UFOs, you might look at what other unconventional beliefs you have.
Im not signing on to the UFO religion, so call me anagnostic.
