“Purple planets: A new sign of potential alien life found by researchers.”
It’s likely for astronomers combing the cosmos for signs of extra-terrestrial life to stumble upon a habitable planet
That scarcely resembles Earth. Such a world may even be purple, researchers found.
To observers from outer space, Earth’s vast oceans and verdant landmasses make
Ut appear as a blue world punctuated by green ecosystems.
It’s the only habitable world we humans have ever known, so of course it’s understandable for us to assume
That the conditions that allow us to survive would be the standard for other life-sustaining planets.
But it’s far more likely for astronomers combing the cosmos for signs of extra-terrestrial
Life to eventually stumble upon a habitable planet that scarcely resembles Earth.
While fields, forests and jungles have made green the colour most associated with surface life on Earth.
That may not be the case for other planets, according to a new study from researchers at
Cornell University’s Carl Sagan Institute.
In fact, the astrobiologists who authored the report contend that it’s not ludicrous to think
That another habitable planet could be, say, purple.
How is that possible?
Researchers say that our own planet could paradoxically offer vital clues as to how a world covered in bacteria that receive little or no visible light and oxygen could retain a purple hue.
“We think about green plants and then blue oceans and then another pale blue dot,” Lisa Kaltenegger, a Cornell University astronomer and director of the Carl Sagan Institute named for the famed astronomer, said in a video shared by the university.
“But when you go deeper and look at the incredible diversity of life on our planet, there are so many different organisms that could dominate another world.”
Purple Planets Could Be the Signs of Alien Life
In the search for extra-terrestrial life, scientists already know that we might be looking for a world that’s very different from Earth’s verdant, plant-dominated biosphere.
Exactly how different is hard to know.
But our own planet can still offer us some clues about alienin purple planet.
There are, for example, organisms that can live in environments very inhospitable to most other life on Earth.
But what would an alien equivalent of plant life look like?
Well, life here on Earth offers another possibility for that, too.
While a significant proportion of producers here contain green-hued chlorophyll for survival, photosynthetic bacteria that thrive in low-light conditions tend to be colored purple to make the most of infrared radiation.
“Purple bacteria can thrive under a wide range of conditions, making it one of the primary contenders for life that could dominate a variety of worlds,” says astrobiologist Lígia Fonseca Coelho of Cornell University’s Carl Sagan Institute.
“They already thrive here in certain niches. Just imagine if they were not competing with green plants, algae and bacteria: A red sun could give them the most favourable conditions for photosynthesis.”
The most abundant stars in the Milky Way galaxy are not like the Sun; rather they are smaller, redder, emitting significantly less heat and light than our own star.
Up to 75 percent of all stars in the galaxy are red dwarf stars, which leads scientists to speculate whether life can emerge on a red dwarf explant
what it might look like if it did, and most importantly how we could detect it.
The Carl Sagan Institute has been on a quest to catalogue different forms of life
And work out what they might look like from afar if we were viewing them on another world.
Here on Earth, the photosynthetic pigment seen most often in plants is chlorophyll-a.
This is also found in cyanobacteria, which is no accident.
The chloroplast in plant cells that contains the chlorophyll pigment is actually a symbiotic cyanobacteria
That was taken up into the ancestors of modern plants a long time ago, and co-evolved to allow their hosts to photosynthesize.
Searching for signs of life on exoplanets
Along with organizations like the Search for Extra-terrestrial Intelligence (SETI) Institute
The Carl Sagan Institute is among the rare groups fully focused on exploring the cosmos for signs that we are not, in fact, alone.
To answer that question, astronomers have increasingly turned to finding and studying exoplanets
which orbit stars outside our solar system.
To date, 5,500 of these planetary bodies have been discovered.
But it’s rare for any to be located in the so-called habitable zone a region were water could remain in liquid form and pool
on the planet’s surface and also have conditions similar to Earth that could support life, according to institute.
