Harvard astronomer wonders about extraterrestrials
Only 5 spacecraft from Earth are now heading out of our solar system. None are directed to a star system. Even if they were, they wouldn’t reach another star system for tens of thousands – or hundreds of thousands – of years.
Avi Loeb is a Harvard astronomer who entertains the idea of extraterrestrial civilizations. He proposed that ‘Oumuamua, an interstellar object that passed through our solar system in 2017, could be an alien spacecraft. He wondered if extraterrestrials had created our universe in a laboratory. Last month, he suggested that a 2014 meteor that hit the Pacific Ocean could be alien technology. And on April 27, 2022, he emailed EarthSky with an analogy explaining how one of our spacecraft could crash into another world, creating an “alien artifact” for a distant civilization.
Our spaceships as extraterrestrial artifacts
Late last month, I exchanged emails with Loeb about the 2014 meteor – possibly from outside our solar system – which landed in the Pacific. Loeb wants to mount a search for it, as it could be alien technology. To prove his point, Loeb shared an analogy — in this case, a made-up story — based on historical facts about the 2014 meteor — with EarthSky. He used the example of NASA’s New Horizons spacecraft, which visited Pluto in 2015 and is now heading outside our solar system, to describe what an Earth spacecraft might look like in an alien world. He wrote:
Imagine the New Horizons spacecraft continuing its interstellar journey for a billion years and eventually crashing into a habitable planet around a distant star. His equipment would then be extinguished, just a piece of space junk composed of heavy elements with a rough surface cratered by numerous impacts of interstellar dust, gas and cosmic ray particles.
Now imagine the astronomers of this exoplanet discovering this technological junk as it approaches them under the lamppost of their parent star, which illuminates the darkness around them. They use their most advanced telescope to survey the skies for objects that could impact their planet, a warning system to prevent disasters caused by space rocks. But this object does not appear to behave like a common asteroid or comet they had seen many times before. In particular, the object does not have a cometary tail. Yet it appears to be pushed away from the star by a force that decreases inversely with squared distance due to the star’s radiation pressure on its walls.
Answers from “experts”
After hearing a symposium on the anomalies of this object, one of the [alien] space rock experts say: “This object is so weird, I wish it never existed.” Other experts choose to write a review article in a prestigious journal and argue that it must be a natural object and there is no reason to suspect anything else about it. the basis of their extensive knowledge of space rocks.
Months later, a team of other experts claim that this object is a rock of a type they had never seen before, namely a hydrogen iceberg, and that is why the cometary tail is invisible. Another team suggests the object is a dust bunny, driven by light. And a third team of experts argues forcefully that it must be a nitrogen iceberg, chipped off the surface of a distant planet.
In collision with the planet
Loeb’s analogy continues:
The consensus among all experts is that even if the object is heading on a collision course with their planet, nothing should be done to deviate its course, because all likely explanations for its origin – a hydrogen iceberg, a rabbit of fluffy dust or a frozen lump of nitrogen – imply that the object will quickly burn up in the planet’s atmosphere and nothing will survive to damage the surface.
The most sophisticated government satellites monitor the object’s plunge into the atmosphere. They believe their data could decide which of the experts’ three explanations is correct, based on how quickly the object is burning and what gases predominate in its fireball.
As New Horizons crashes into the planet’s atmosphere, it defies all expectations. The fireball occurs at a much lower altitude than expected for a dust bunny or alien icebergs.
The light curve of the meteor in the lower atmosphere implies that the composition of the meteor was much harder than an ordinary rock. Its material resistance is far superior to that of any stony meteorite, let alone a dust bunny or exotic icebergs.
The astronomical community refuses to believe government data because it does not include measurement uncertainties. These uncertainties are classified for national security purposes because the sensors used to collect the data are classified. After three years, the government released a letter, along with the light curve of the fireball, stating that the object is highly unusual in its composition at 99.999% confidence. In response, experts are widely quoted in the papers as saying a letter from the government is not the way science is done and since the real data is classified – they will never know what that means.
In search of extraterrestrial artifacts
Loeb’s analogy concludes:
But a small group of scientists decide to dig the ocean floor at the impact site and search for meteor fragments that survived the fireball. When they lead the expedition, they find a small box at the bottom of the ocean that was attached to the New Horizons spacecraft. The box contains thirty grams of the ashes of Clyde Tombaugh, a “human” who discovered a planet called “Pluto”. They immediately conclude that the interstellar meteor must have been a technological relic of a so-called “human civilization” that launched it a billion years ago.
And they also argue that this “human civilization” wasn’t particularly smart because it destroyed the genetic information about the person it wanted to memorialize. Tombaugh’s DNA was burned into ashes that are no different from the ashes of a cigarette. It involves a primitive ritual that makes little sense to an intelligent scientific community. “If the humans are still out there, we want nothing to do with their destructive mindset,” they conclude in their report. End of the story.
An analogy with the 2014 meteor
Loeb’s analogy for the 2014 interstellar meteor is part rant, part response to his detractors. It reimagines our very own interstellar spacecraft reaching another world many, many years in the future. He asks that surely, if it could happen on another world, couldn’t it happen here?
The above scenario is grounded in facts. Anyone who knows me could testify that I don’t like science fiction.
Conclusion: Harvard astronomer Avi Loeb ponders what might happen if an Earth spacecraft crashes on a distant planet inhabited by intelligent aliens.