“Exist at an Astonishing Scale” –Planets Orbiting Black Holes Could Harbor Life ‘Beyond Extreme’

Black Hole Planet

 

“The black holes of nature are the most perfect macroscopic objects there are in the universe –the only elements in their construction are our concepts of space and time,” said Subrahmanyan Chandrasekhar, the Noble-Prize winning, Indian-American astrophysicist NASA’s Chandra X-Ray Observatory was named for.

Astronomers are  speculating that planets by the thousands may be orbiting in a “safe zone” captured by the massive gravitational force of these paradoxical, terrifying, “perfectly constructed” spacetime objects. In 2019, Harvard’s Avi Loeb and NASA’s Jeremy Schnittman, suggested that inhabited planets might exist around the black holes harbored at the center of most galaxies similar to the fictional waterworld planet orbiting the supermassive black hole Gargantua in the movie Interstellar.

It’s possible, they suggested, that extreme forms of life life may form on some of these planets.”We have known since the 1990s that planets exist around pulsars”, said Harvard’s Loeb. “It’s reasonable to assume that planets might also exist around black holes, which, perhaps surprisingly, have a much weaker impact on their environment than pulsars.”

“The Gargantua Hypothesis” –Habitable Planets May Be Orbiting Black Holes

Inhabited planets, says Loeb, might exist around the black holes that lie at the cores of most galaxies. It’s even possible that life may form on some of these planets, given that organisms on Earth have adapted to extreme conditions, including boiling heat, freezing cold, and acidic, highly salty and even radioactive environments.”

“Microbial Astronauts”

We know that Earthly microbes such as Bacillus subtilis, Caenorhabditis elegans, Deinococcus radiodurans, Escherichia coli and Paracoccus denitrificans have been shown to live through accelerations just one order of magnitude smaller than millions of gs. If these mini astronauts, suggests Loeb, could survive a ride through the Interstellar medium of the Milky Way who knows what could exist on a safe-zone blanet.

Milky Way’s “Extremely Extreme Life”

Earth’s most indestructible species, the extremophile, tardigrade, an eight-legged micro-animal, will survive until the Sun dies, according to a 2017 Oxford University collaboration, The Resilience of Life to Astrophysical Events, begs the question: what else is out there? “Tardigrades are as close to indestructible as it gets on Earth,” the researchers reported, “but it is possible that there are other resilient species examples elsewhere in the universe.”

Supermassive Planetary Systems May Exist of Astonishing Scale

Fast forward to 2020, a team led by Keiichi Wada of Kagoshima University in Japan proposes a new class of exoplanets that form directly around active supermassive black holes at the hearts of galaxies existing in a “safe zone” up to tens of light-years away, beyond the danger of the event horizon physics. These black hole planets, Wada christened, blanets, might form from coagulated grains of dust swirling around the black hole. “Our results suggest that ‘blanets’ could be formed around relatively low-luminosity active galactic nuclei during their lifetime.”

“Our calculations show that tens of thousands of planets with 10 times the mass of the Earth could be formed around 10 light-years from a black hole,” said astronomer Eiichiro Kokubo of the National Astronomical Observatory of Japan noting that planet formation dynamics are likely the same in the outer reaches of the black hole discs as you see in a protoplanetary disc. Supermassive black hole discs contain more dust – up to a billion times more than a protoplanetary disc, according to the researchers. “Around black holes there might exist planetary systems of astonishing scale.”

“The Invisible Galaxy” –100 Million Black Holes Lurking in the Milky Way

“The total amount of dust is enormous,” says Wada. This means the typical mass of planets would probably be large – about 10 times more massive than Earth – and there could be as many as 10,000 of them around a single black hole.”

“Possible for Millions of Planets in Orbit”

Sean Raymond at the University of Bordeaux, reports New Scientist, says it might be possible for planets to form closer to a supermassive black hole and to exist in even higher numbers. “It is theoretically possible for millions of planets to orbit a supermassive black hole, but it requires a lot of things to be just perfect,” he says.

Astronomers estimate that the Milky Way contains an estimated 1 billion neutron stars, of which about 200,000 are pulsars –neutron stars of only 10 to 30 kilometers in diameter with enormous magnetic fields, that accrete matter and regularly burst out large amounts of X-rays and other energetic particles. So far, 3000 pulsars have been studied and only 5 pulsar planets have been found. In 1992, the first exoplanets ever were discovered around pulsar PSR B1257+12.

Enormous Atmospheres

In 2017, scientists at Leiden University and Cambridge University reported that it is theoretically possible that habitable planets exist around pulsars. Such planets must have an enormous atmosphere that convert the deadly X-rays and high energy particles of the pulsar into heat. This was the conclusion of the paper by astronomers Alessandro Patruno and Mihkel Kama who suggested that there could nonetheless be life in the vicinity of these stars.Their calculations show that the habitable zone around a neutron star can be as large as the distance from Earth to the sun.

The Daily Galaxy, Max Goldberg, via National Institutes of Natural Sciences, Netherlands Research School for Astronomy and Scientific American

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