People have high expectations for the new James Webb Space Telescope as it continues — so far flawlessly — toward its permanent home at the Lagrangian 2 position on the far side of the Moon.
The media say it will show us the birth of the universe. And reveal which exoplanets have life. Sounds great. But if you’re a realist, pull up a chair.
First off, the earliest period of the universe was already detected over a half century ago. That’s the nearly-uniform microwave radiation that comes at us from the entire sky. It’s the now-redshifted blaze of light that suddenly filled the cosmos when the universe finally cooled enough for individual atomic particles and atoms to form. Before that, meaning the first 389,000 years after the Big Bang, the cosmos was opaque. Light couldn’t even travel one foot without being absorbed. But when the cosmos became transparent, light abruptly zoomed in all directions and it’s never stopped.
The universal expansion of space has stretched out that light until each wave of energy is now nearly a foot from crest to crest. Meaning, it’s all been redshifted into the radio spectrum, and is part of the static you can hear between stations on your TV or radio, unless you can only receive the newer digital broadcasts. Anyway, that’s the oldest possible “light” we can observe. The earliest information we can get. That part of the radio spectrum is termed “microwave” and we’ve been studying it since the sixties.
In addition, large existing telescopes can see very distant and hence old objects when they were so young we can watch them being formed. It reveals that the cosmos has an evolution process going on, which is why we observe more spiral galaxies far away, and more of the newer merged galaxies, which look like enormous balls, when we peer closer to us. Webb will reveal more detail in distant newly-born galaxies. But forget about telling us about the universe’s birth.
That’s because there’s no way for Webb to detect the antecedent conditions that led to the Big Bang. And barring that, there’s no way to explain how an entire universe popped out of nothingness one Saturday morning. It’s an insuperable mystery and will remain that way. Not to mention that many cosmologists, thanks to the perfectly flat overall topology of space uncovered in 2014, are starting to think the cosmos may be infinite in extent and eternal in duration.
Item two is that alien life business. Webb may be able to spectroscopically detect the composition of exoplanets’ atmospheres. If it finds certain gases like free oxygen, that would be strong evidence for the presence of life – or at least plant life. Say it happens. Say we suddenly learn that a nearby star’s planet, perhaps a mere 90 light years away, probably has life. Then what? We can know nothing more unless we send an orbiting probe, which would take at least 5,000 years to make the trip. That’s five thousand predictable years of speculation by religious crazies, New Age crazies claiming they’ve received “vibes” and “psychic messages” from the ‘advanced beings’ there, and even science crazies who will publish endless speculative analyses based on poor or nonexistent evidence. It’ll be one Dr. Oz after another, a parade of nonsense that will last the next 250 generations. From where I sit, this seems inevitable and frustrating. You don’t see that coming? You’ve dozed off the past six years and imagine we’re a nation of rational people?
So much for the two main headline-grabbing predictions for what Webb will bring us. Fortunately, its unprecedented infrared capabilities will also deliver exquisite new discoveries. Some will be total surprises. It will be these that will surely bend our minds in real-time, since they will out-compete that other stuff for serious researchers and the more rational among us.
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