“Space is really, really big.” ~Dr. Michael Wall
Mike admits that he got interested in what was out there during the camping trips he took as a kid, when he could see the stars in a dark night sky, and he relates that, with all the stars in the galaxies of the universe, there is likely to be life beyond the Earth.
Where the image of Powehi, the black hole photographed in M87 in April 2019, is concerned, Mike remarks that the visible part of the image is the boundary of the event horizon, as not even light can escape a black hole’s gravitational pull. The silhouette of the black hole is the fuzzy darkness in the middle of the circle of light, and given that it took light from Powehi 55 million years to get to the Earth, it’s not surprising that the image is, as a lot have complained, fuzzy. Mike notes that scientific theories on relativity and on black holes can now be tested using Powehi, and that Einstein’s theories on gravity and general relativity are proven correct.
The most likely form of life humans would run across, Mike opines, would be single-celled, microbial in nature as, based on our own history, microbes have existed alone on Earth for some three billion years before multicellular life appeared. Mike notes that this apparently indicates that there is a hurdle between microbial and multicellular life, which means that multicellular life, while possible, would likely be rarer than microbial life.
Mike notes that it is possible for highly technological civilizations might exist, but we humans would need to overlap in time with the other civilization we would like to get in touch with. It is also likewise possible that a technological civilization does exist, but the vastness of space means that two technological civilizations connecting with each other would be challenging.
Life on other worlds does not necessary have to rely on the same kind of chemistry of life on Earth, but Mike notes that carbon is commonplace throughout the universe and works well with liquid water, which is why carbon-water based life is probably the most common kind of life in the universe. That said, silicon has similar chemical properties as carbon, which means that silicon-based life forms might exist. Mike also notes that there are presently unproven, but presently possible, theories that life on Earth could have started by organic substances which were brought to the Earth by the rocks and dust that fell to it (panspermia).
At present, human space travel is on “an upward trend,” according to Mike, due mainly to privately funded efforts, rather than efforts funded by the United States government, which are at the mercy of political whims. Propulsion for space travel will, for the next decade or two, be based on rockets, and Mike notes that some other possibilities to get up to high speeds for interstellar travel would be engines powered by fusion reactions as well as by energy sails which would get energy from either the sun or an Earth-based laser.
Antimatter is essentially a “bizarre version” of the matter we humans are used to, like positrons, which are positively charged particles which have the same mass as electrons, and are thus the antimatter equivalent of an electron. When an antimatter particle meets its matter counterpart, an explosion takes place, releasing energy in a 100% conversion from mass to energy. This makes for a powerful energy source, but large amounts of antimatter are difficult to create, and the antimatter itself has to be trapped in a magnetic field so that it can’t touch any matter.
Multiple universes can exist, and Mike notes that most theoretical physicists believe that these do exist, with our own universe just being one of these. The other universes also do not have to look like ours, as they can exist with more dimensions than we are used to, and universes where magic is more prevalent than physics can likewise be possible. Where our own universe is concerned, Mike points out that present theories of the universe, based on our observations, indicate that the universe is likely to be infinite; and if our own universe is infinite, so, too, might those other, alternate universes. An infinite universe also presumes that whatever one can think up can come into being, such as an imaginary creature, and that there could also be alternate versions of everyone who has existed on earth, although these would exist far away; and the possibilities increase with multiple universes.
Mike hopes OUT THERE gets across to people the sense that something big is happening in science and exploration, and he hopes that people can connect with the wonder and the energy that is present in today’s space exploration efforts. He believes that it will take ten to fifteen years before we can get answers to some of the questions we have been asking for a long time now.
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