This is the episode for anyone who has wondered about the fundamental structure of the universe and its extremely distant future — a time which is so distant that for all practical purposes, it’s almost synonymous with eternity. Black Holes, Fundamental Physics, and the meaning behind the cosmological catchphrase — Turtles All the Way Down. Please listen.
What happens when all the stars in our cosmos’ galaxies burn out; with little or no hydrogen gas left to fuel star formation; and everything pretty much turns to toast? It will presage an age of black holes where extremely low temperatures and fundamental particle decay will alleviate life as we know it. This universal endgame in an almost infinite far future may actually be a Dark Age where little or nothing can happen. And if it does, only on the longest timescales. Yale University astrophysicist Gregory Laughlin and I discuss these and other issues in this cosmological “turtles all the way down” episode of the podcast.
In a recent study of the upper atmosphere of Venus, finding the chemical fingerprint of phosphine has led to speculation that it may be tied to airborne life high in the clouds of our sister planet [1]. We harbour similar suspicion of microbial life on Mars [2], Saturn’s moon Enceledus [3], and Europa, the icy Galilean of the Jovian system [4]. The dwarf planet Ceres of the asteroid belt could be added to that list also, with recent evidence of oceanic water [5], while more exotic variations of life may exist on Titan, which is known to be teeming with organic materials [6]. Should we be more wary of our Solar System as an environment to explore, and the potential of pathogens we may encounter?
If one rewinds 500 years, to when exploration of new worlds involved sailing the oceans, the discovery of the Americas introduced viruses which decimated the native population at that time [7]. That in itself was far from a unique event in history, of course. There have been many occurrences throughout history where travel between distant lands has resulted in the introduction of devastating plagues to one population or the other — not least the Black Death, which arrived in Europe from commercial travel with Asia in the 1300s [8]. Meanwhile, 2020 has reminded us how a novel virus can prove virtually unstoppable from spreading worldwide in a matter of months and reaching pandemic level, once introduced to our now interconnected world [9].
Indeed when the first astronauts returned from the Moon in the 60s, they had to undergo weeks of quarantine as a precaution against introducing a lunar pathogen to Earth [10]. We now know the Moon to be a sterile world, but this should not give us a false sense of security when visiting and returning from other worlds, which are far more likely to harbour microbial life. It is quite plausible to consider that any microbes which have evolved to survive in the harsh environments on other worlds could multiply out of control if introduced to a more fertile environment on Earth. The likelihood of any such foreign microbes being capable of becoming infectious pathogens to our species is difficult to measure, but one could still cause problems regardless, by undermining Earth’s ecosystem in competing with native microbial life as a runaway invasive species.
Fortunately, due to the vast distances involved in inter-planetary travel, returning astronauts would likely show symptoms of infection from any dangerous pathogen long before reaching home, as such a journey would be expected to take many months, even with more advanced propulsion technology than we use in space travel today. That is not to say they could not inadvertently return with microbial life on board — or even on the exterior of craft: Earth’s tardigrades, for example, have proven quite durable in journeys into outer space [11].
Grady believes creatures could be living in glacial oceans underneath a hard shell of ice that’s up to 15 miles thick on Jupiter’s frigid moon.
Scientists have long suspected the existence of these deep subsurface oceans on Europa — and maybe even life. In fact, NASA announced in August that it’s completing the final designs for a Europa-bound spacecraft called Europa Clipper, which will look for signs of life.
2016 gave us a fair number of false SETI detections. But lets imagine that this year it’s the year.
Maybe it’s first detected at a radio telescope in Russia, or perhaps an optical telescope in California. But in 2017, somewhere someone picks up a signal. Skeptical astronomers alert their colleagues, yet sure enough, they’re reading it out in telescopes around the world. It’s too specific or too weird to be a known natural phenomenon, and it repeats itself with suspiciously high fidelity over some interval. Cautiously, but excitedly, the news gets out. We’ve received a message from the stars.
Today, the Moon is about as inhospitable to life as it gets. The little water that’s there is trapped in ice or rock. It’s otherwise dry and airless, fluctuating in temperature by hundreds of degrees anywhere the sun shines. But long ago? That’s an entirely different story.
New research published in Astrobiology suggests that the Moon may have been shockingly habitable in the past during at least two periods — shortly after the Moon formed, and when volcanic activity was at its highest.
The key to it all is heat and lots of energy. The Moon formed after a collision between Earth and a proto-planet astronomers call Theia. And just after the smash up, there was lots of water vapor — enough that the Moon could’ve had a fairly substantial atmosphere and pools of water on the ground. Volcanic activity was also high, which could have replenished the atmosphere with water vapor from deep in the interior.
Wow, 😳 this video is excellent. Unleash your imagination and think about a Museum of Alien Life 👾👽
« What if there was a museum that contained every type of life form in the universe? This experience takes you on a tour through the possible forms alien life might take, from the eerily familiar to the utterly exotic, ranging from the inside of the Earth to the most hostile corners of the universe.
Yes, it is True! A Tesla car is cruising space! The founder of SpaceX Elon Musk wanted to launch a ‘silly’ payload for SpaceX’s Falcon Heavy rocket debut flight because a rocket’s first flight has potential to fail. Typically, aerospace companies launch massive concrete blocks as mass simulators during risky rocket flights. As the dreamer that Musk is, he opted to launch something that would inspire the public to dream big and look at the stars — his flashy midnight cherry Tesla Roadster. The electric vehicle became the crazy payload for the rocket’s launch.
On February 6, 2018, SpaceX conducted Falcon Heavy’s debut flight; It lifted-off from historic launch Pad 39A at NASA Kennedy Space Center in Cape Canaveral, Florida. The successful test turned Falcon Heavy into the most powerful rocket in operation, it produced about five million pounds of thrust (22MN). During the mission, SpaceX shared Live footage as the Tesla Roadster was placed into orbit. It was a very inspiring to watch an actual car orbiting around Earth with, a mannequin dressed as an astronaut, positioned in the Tesla driver’s seat; while the radio played “Life on Mars” by David Bowie (video below). After the awe-inspiring launch, Musk wholeheartedly said — “Life cannot just be about solving one sad problem after another. There need to be things that inspire you, that make you glad to wake up in the morning and be part of humanity. That is why we did it. We did for you.”
Astrobiology students cultivated leafy greens, sweet potatoes, and even hops in simulated Martian dirt.
NASA and private entrepreneurs are pushing to land people on Mars within the next generation. To survive on Mars, colonists will need a lot of gear, not least of which is food. Since lugging food adds a lot of weight to spacecraft — and packaged food only retains its nutrients for so long, anyway — any would-be Martians will need to grow food on site in order to survive.
