But astronomer Tiger Hsiao of National Tsing Hua University says we might be looking for the wrong thing. In a new study, he and colleagues set out to calculate whether it would also be possible to use a Dyson sphere around a black hole. They analyzed black holes of three different sizes: those five, 20 and 4 million times the mass of our Sun. These, respectively, reflect the lower and upper limits of black holes known to have formed from the collapse of massive stars—and the even more enormous mass of Sagittarius A*, the supermassive massive black hole thought to lurk at the center of the Milky Way.

Black holes are typically thought of as consumers rather than producers of energy. Yet their huge gravitational fields can generate power through several theoretical processes. These include the radiation emitted from the accumulation of gas around the hole, the spinning “accretion” disk of matter slowly falling toward the event horizon, the relativistic jets of matter and energy that shoot out along the hole’s axis of rotation, and Hawking radiation—a theoretical way that black holes can lose mass, releasing energy in the process.

From their calculations, Hsiao and colleagues concluded that the accretion disk, surrounding gas, and jets of black holes can all serve as viable energy sources. In fact, the energy from the accretion disk alone of a stellar black hole of 20 solar masses could provide the same amount of power as Dyson spheres around 100,000 stars, the team will report next month in the. Were a supermassive black hole harnessed, the energy it could provide might be 1 million times larger still.

New definitions of “habitable worlds” could include planets with global oceans under a steamy hydrogen atmosphere or exclude ones that started out habitable but lost all their water.

The hunt for habitable worlds owes a debt to this moment in planetary science history.

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It’s the 40th anniversary of the Voyager 2 flyby of Saturn, which has informed every NASA mission to the ringed gas giant since.

The James Webb Space Telescope is scheduled for launch on October 31. It will help scientists hunt for alien life on exoplanets and look to the beginning of time.

Some highly speculative ideas how life may spread in the galaxy, for more info see.

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There is even more to the astrobiological potential of rogue planets, however. Not only could they hold microbial life bottled up in their subsurface, they may be able to distribute life throughout the galaxy. In our paper we suggest two ways that this kind of panspermia might occur.

If a wandering planet passes close to a habitable rocky planet within a solar system, the outer layer of the rogue planet might be torn apart by gravitational disturbances, and the resulting debris could end up on the habitable world. Dormant life that had been trapped in the icy shell of the rogue planet may become active again and establish a biosphere on the receiving planet.

Alternatively, the two planets could collide, or come close to colliding. This is generally believed to have a sterilizing effect, as when a Mars-sized object (probably a rogue planet!) collided with the early Earth, resulting in the creation of our Moon. But the distribution of energy and matter during such an event would be very uneven, and some localities might not experience temperatures high enough for sterilization. A common atmosphere may even form, which I think was the case for early Earth and Moon shortly after the cataclysmic impact. Some (dormant) microbial life may survive suspended in such an atmosphere for a long time, before eventually settling down when the surface has cooled off and become more habitable again.

The European Space Agency (ESA) and Roscosmos are preparing for the2022launch of the next mission in their joint ExoMars program, which is currently undergoing final testing before shipment to Kazakhstan for a launch in September next year.

The2022astrobiology mission will see the long-awaited Rosalind Franklin rover land on Mars with the help of the Russian Kazachok lander. The lander will also perform experiments on the Martian surface after deploying Rosalind Franklin as the two craft work together to search for signs of past life on the Red Planet.

After construction delays, missed Martian transfer windows, and the COVID-19 pandemic, Rosalind Franklin, Kazachok, and the other ExoMars2022mission systems have been completing important testing milestones ahead of shipment to Kazakhstan for launch on a Proton rocket next year.

Wed, Aug 25 at 9 AM PDT.

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Please join us for a new episode with Dr. Alfonso Davila, an astrobiologist at NASA Ames Research Center! His research focuses on the biological and biosignature potential of terrestrial environments considered to be analogous to extraterrestrial environments, and using that knowledge to develop strategies to search for evidence of life beyond Earth.

This program is an interactive talk show where our guest will answer questions from our host, Dr. Graham Lau, as well as questions submitted via Twitter, Facebook, and SAGANet chat. For more information, visit the official website of Ask An Astrobiologist at astrobiology.nasa.gov/ask-an-astrobiologist.

Scientists at NASA have adjusted their forecast of an Empire State Building-sized asteroid it predicts could potentially smash into the planet.

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Have you ever heard of the phrase “life imitates art?” Well, two scientists are out to prove that science is not exempt. Or, at least, it shouldn’t be. Taking a cue from Star Trek, scientists Dr. Hal Fearn and Dr. Jim Woodward are attempting to build an “impulse engine” to make interstellar travel possible in a human lifetime.

In the Star Trek universe, impulse engines are used to provide a high thrust for a short period to break out of the orbit of a planet or moon. Which also speeds up interstellar travel and allows the team to “boldly go where no man has gone before.” Without that, we probably wouldn’t have a Star Trek franchise or the millions of space-dreaming fans it has accrued. But sadly, space travel is eons behind the sci-fi franchise.

According to Fearn, it would take about fifteen to sixteen thousand years to travel to Earth’s nearest star. So unless real vampires are roaming the world, it’s doubtful that interstellar travel will be reached during any human’s lifetime.