IS THERE LIFE OUT THERE?
In his latest Stargazing column, Wayne HarrisWyrick discusses “The Fermi Paradox”
One summer day in 1950, physicists Enrico Fermi, leader of the team that built the first nuclear reactor, enjoyed lunch with several fellow physicists. Talk turned to recent UFO reports and the possibility of faster than light travel. Referring to aliens, Fermi suddenly blurted out “Don't you ever wonder where everybody is?” This question led to “The Fermi Paradox.”
Simply stated, if (as we now know) our galaxy contains billions of planets, many of them Earthlike, why haven't we ever encountered any aliens? Earth is young, in cosmic terms. Many solar systems older than Earth exist, some billions of years older. If life existed on any of them, it would take no more than 50 million years to colonize the galaxy with the rocket technology being developed at that time, a blink of the eye in cosmic terms. So, Fermi wondered aloud, where is everybody?
Over the years, other scientists have suggested various answers.
Water is essential to life as we know it. Earth's water exists on the surface, but for most of the other worlds in our solar system that possess oceans, four moons, the water is locked underground, below a frozen surface. That may be common for lifebearing planets or moons.
Many of the planets we've discovered that could have water are classified as superEarths, planets up to 10 times larger than Earth. The gravity of such planets may well make space travel impossible.
Futurist and astronomer Seth Shostak, says that all intelligent aliens may actually be intelligent machines. We ourselves are on the verge of creating such machines and, within a few thousands of years, all intelligence on Earth may be machine, not biological.
Some scientists suggest that alien life may be so different from us, we'd never recognize it. Or, perhaps just as we destroy ants without even realizing it when building a house, maybe all other life forms have been eradicated. Or they wiped themselves out with climate change.
Maybe we have met the aliens, and they are us. The “panspermia hypothesis” says life was seeded on Earth by comets (or alien spacecraft?), making us the very aliens we search for.
Even so, we need to keep looking.
Summer legend
At 1:50 a.m. on Sept. 23, the sun sits directly over Earth's equator. This moment of time marks the Autumnal Equinox. An
urban legend claims that only at this exact moment can you balance an egg on its end. The legend is misleading. You can balance an egg on its end just as easily at any moment in the year. But go ahead, try it at 1:50 a.m. on Sept. 23.
Planet Visibility Report
As the month begins, Mercury, Venus, and Mars are too close to the sun to be seen. As September progresses, Mercury and Venus move into the early evening sky and by month's end, or at least early October, both should be visible in the evening twilight. Mars moves the opposite direction becoming visible in late September in the morning twilight. Both Jupiter and Saturn are up in the east at sunset and remain visible in the evening sky all month. The moon becomes full on Sept. 13 and hits the new phase on Sept. 28.