Facts About the Search for Extraterrestrial Life in the Universe
In 2017, a global survey suggested that half of all Earthlings believe in “in the existence of intelligent alien civilizations in the universe.” When asked if they believed in “some form of life on other planets,” those responding yes rose to 61 percent.
Interestingly, the number of Americans who believe in alien life has risen in recent years, following the 2019 New York Times reports about UFOs. Following the public release of the Pentagon’s UFO video footage, the Navy created a new protocol for pilots to report sightings.
Since then, interest in alien life has been growing, leading Gallup to poll Americans about UFOs for the first time in decades. According to the poll, 60 percent of Americans thought UFOs were natural phenomena or human activity. However, 33 percent believed extraterrestrials could pilot UFOs.
On the other hand, a 2020 poll from Ipsos concluded, “nearly two-thirds of Americans believe that there is life on other planets and a bare majority hold that intelligent life and civilizations exist outside of Earth.”
Whatever these UFOs are, the interest in extraterrestrial life is growing. So, we’ll look at some facts on the search for life in the universe. Judging purely by facts alone, we can’t say for sure if extraterrestrial life exists, but we also can’t rule it out.
Alien Life May Resemble…Pasta?
When most of us think about what an alien looks like, the image that may come to mind could be derived from stories about the 1947 Roswell incident. In these stories, aliens are often depicted as the so-called Grey Aliens, with large eyes, enlarged heads, and frail bodies.
However, a 2019 NASA-funded study concluded that if extraterrestrial life exists, it is more likely to resemble pasta. The researchers pointed to fettuccini-like rock formations found in hot springs at Yellowstone National Park. There, hot acid water is home to filamentous microbe mats that produce the noodly rock formations.
A nursery of microbialites emerging from a microbial mat along the edge of a thermal stream flowing from a hot spring in Yellowstone National Park— ITBT Karnataka (@ITBTGoK) May 27, 2018
Source: Life at the Edge of Sight: A Photographic Exploration of the Microbial World pic.twitter.com/JwwjlFq31d
These microbes break down sulfur for energy and evolved 2.5 billion years ago when the atmosphere was almost devoid of oxygen. Now, if a future space rover picks up a similarly-formed rock, it could be a tip-off of life. Thus, life on Mars could resemble the lifeforms eeking out an existence in inhospitable environments here at home.
Possible Life on Venus?
In 1967, Carl Sagan wrote that life could exist in the clouds on Venus. Although the surface is hotter than the melting point of lead, there are cooler areas in the middle atmosphere. There, sulfuric-acid droplets could provide a home for microbes.
Now, a new study points to the existence of phosphine in Venus’s atmosphere, a chemical generally produced naturally as organic matter decomposes.
Telescopes in Hawaii and Chile detected phosphine in the Venusian clouds. Researchers believe the phosphine could be a biosignature indicating that microbes are at work on Venus.
Prior to this discovery, scientists learned that the presence of water in the atmosphere indicates Venus once had oceans. In these oceans, now long-evaporated, microbes may have evolved and then taken to the atmosphere.
However, scientists also suspect that if microbes exist on Venus, they may have arrived when rocks blasted away from Earth or Mars. Or, the microbes may have come aboard contaminated space probes from the Soviet Union and the United States in the 70s and 80s.
Life on the Moon?
Strangely, there may also be microbes from Earth living on the Moon. On April 11, 2019, an Israeli moon mission Beresheet crash-landed on the Moon. The lunar lander was holding thousands of microbes called tardigrades, microscopic “water bears.”
RECOMMENDED READ: Facts About the Moon That You Should Know
The water bears were in cryptobiosis, a state of suspended metabolic activity. Though it’s unlike they survived, the tardigrades are among the most resilient living things dubbed extremophiles. The little eight-legged animals can go without food or water for 30 years. Not to mention, they can survive temperature extremes to absolute zero or above boiling. Plus, they can survive extreme pressures and the vacuum of space.
Desiccated on the Moon, the water bears may remain dormant. However, technically, there could be life on the Moon. Strangely, there is another possibility for life from Earth on the Moon. When the astronauts visited the Moon, they left behind bags of poop. Inside these bags of poo, scientists suspect gut bacteria may still be present.
— Dallas Campbell (@dallascampbell) January 15, 2019
In January 2019, the world learned that China began growing cotton seeds on the far side of the Moon. As part of the Chang’e 4 mission, the plants were sealed aboard the Moon lander.
SETI Confirms Earth-Like Exoplanets
The SETI Institute, founded in 1984, has a mission of searching for extraterrestrial intelligence. Today, the search has entered the mainstream after discovering more than 3,000 exoplanets outside our solar system. According to SETI’s senior astronomer, one in five or six of these planets could be Earth-like. Thus, they are rocky and are in the “Goldilocks zone,” allowing liquid water to form.
Even if it’s just pasta-like, scientists suspect extraterrestrial life could inhabit some of these exoplanet systems with a few standouts such as:
- Proxima B
- TRAPPIST-1 System
- LHS 1140b
- Ross 128 b
- GJ 1214b
Also, some of Jupiter’s and Saturn’s moons could be a home for life in liquid oceans under the surface.
Lastly, we must mention Mars, the Red Planet. Since 2015, NASA has known there is liquid water on Mars. Rolling down steep Martian slopes, the water appears seasonally, and the source remains a mystery.
In December 1984, geologists in Antarctica discovered an ancient meteorite dubbed ALH84001. By 19993, researchers realized the rock was from Mars and formed from volcanic lava 4 billion years ago. Thus, it predated any rock on Earth and could be almost as old as the Solar System. However, it landed on Earth some 13,000 years ago after drifting in space.
#OTD August 6, 1996, a team of researchers led by NASA scientists including lead author David S. McKay published an article in Science claiming that the meteorite ALH84001 may contain trace evidence of life from Mars after Electron microscopy revealed ch… https://t.co/MFs7Fr5p4u pic.twitter.com/kUtqa3caiz— The Interplanetary Podcast (@Interplanetypod) August 6, 2020
In 1994, NASA geochemists discovered that the meteorite contained microscopic shapes suggesting microbes similar to those on Earth. After further scrutiny, researchers found evidence of complex organic molecules, potential fingerprints of life.
The findings were reviewed by Carl Sagan, published, and ended up at the White House. Inspired, President Bill Clinton addressed the nation about the findings on August 7, 1996. (see below)
“Today, rock 84001 speaks to us across all those billions of years and millions of miles,” Clinton said. “It speaks of the possibility of life.”
“If confirmed, he added, the implications ‘are as far-reaching and awe-inspiring as can be imagined,” he continued.
Today, after twenty years and dozens of studies, the consensus remains that the ALH84001 formations indeed happened on Mars. Specifically, according to ScienceFocus, “the carbonates deposited in a watery environment at temperatures around 25-30°C.”
Thanks to the discovery, the search for life on Mars got a big boost, though definitive proof remains elusive. However, studies in the Mars-like Atacama Desert of Chile point to the possibility that microbes could exist beneath the Red Planet’s surface.
There, in the dry Mars-like environment, researchers found that “microbial life is able to efficiently move across the driest and most UV irradiated desert on Earth.”
Thus, extremophiles like those on Earth could well exist on other worlds. For now, we continue the search. Hopefully, one day, we will know for sure. In 2015, NASA chief scientist Ellen Stofan predicted that day could be as soon as 2025.