Harvard scientists suggest 'Oumuamua is an alien device
It's an asteroid, it's a comet, it's actually a spacecraft?
- 'Oumuamua is an oddly shaped, puzzling celestial object because it doesn't act like anything naturally occurring.
- The issue? The unexpected way it accelerated near the Sun. Is this our first sign of extraterrestrials?
- It's pronounced: oh MOO-uh MOO-uh.
That odd-shaped visitor from beyond our solar system, 'Oumuamua (Hawaiian for "scout"), has been fascinating from the moment it arrived: It's a spaceship, it's a rock, it's a comet, it's not a comet. But is it a spaceship? That's where its behavior has some scientists at Harvard leaning; they suggest it may be a device of some kind powered by a lightsail, or a piece of one.
What's got experts so puzzled about 'Oumuamua is, as an about-to-be-published paper says: "'Oumuamua showed deviations from a Keplerian orbit at a high statistical significance." In English: It sped up as it approached the Sun. Comets can do this, but 'Oumuamua has been disqualified as an active comet, as it has no tail. Shmuel Bialy and Abraham Loeb, the authors of the paper, propose that the increase in speed could be due to "solar radiation pressure." The bottom line, they say, is that the discrepancy "is readily solved if 'Oumuamua does not follow a random trajectory but is rather a targeted probe." The paper discusses the math involved and finds that its "general results apply to any light probes designed for interstellar travel."
What we saw is what we get
That dot in the center is an actual image of 'Oumuamua.
'Oumuamua's gone from our view at this point, so any analysis of it or its movements is limited to the data collected during its period of observability. It was first spotted from the PAN-STARRS telescope on Maui (hence its Hawaiian name) on October 19, 2017, and by January 2018 it was gone. Any conclusions we draw have no way of being tested now.
At the time, 'Oumuamua was scanned for radio waves — a basic means of communicating which we assume/hope is the universe's lingua franca — and no radio waves were found, leading observers away from suspicions that its origin could be an alien civilization.
At first, 'Oumuamua was assumed to be an asteroid, but its subtle gain in speed as it drew near the Sun suggested a comet, and it still could be one, though of a kind with which we're unfamiliar. Comets accelerate near the Sun because, as NASA puts it, "Light and other radiation from the Sun push on the gas and dust in the coma, blowing the material away to form a tail that can be millions of kilometers long." The problem with 'Oumuamua is that it had no observable tail. In fact, we couldn't see it that well at all. As you can see in the photo above.
What did 'Oumuamua really look like?
We're all familiar with the shape ascribed to 'Oumuamua, as seen at the top of this article, but since the images really captured of 'Oumuamua showed it as a far-away dot, its presumed shape is a mathematically derived guess based on the way its brightness fluctuated, suggesting a tumbling, elongated object 10 times as long as it was wide. (Current calculations put 'Oumuamua at about 800 meters long.) The rest of its appearance was likewise deduced by its behavior. What many take to be its true appearance is just an artist's conception. So, we're used to feeling like we know what 'Oumuamua looked like, but we don't really know. If you find yourself thinking, "it sure doesn't look like an alien device," well, maybe.
Is 'Oumuamua a lightsail that remains from a larger craft?
The paper offers two theories, either of which would explain 'Oumuamua's odd acceleration. The first is that, "'Oumuamua is a lightsail, floating in interstellar space as a debris from an advanced technological equipment. Lightsails with similar dimensions have been designed and constructed by our own civilization, including the IKAROS project and the Starshot Initiative." Citizen-funded Planetary Society plans to launch one, simulated in the gif above, soon.
A lightsail is a device that uses in-space energy to propel craft via solar pressure. It uses the momentum from solar photons striking a large, thin, reflective sail. What's so interesting about craft powered by lightsail is that they can pick up the energy they need as they travel, rather than storing heavy fuel onboard.
Could 'Oumuamua be an actual probe deliberately sent here?
"A more exotic scenario is that 'Oumuamua may be a fully operational probe sent intentionally to Earth vicinity by an alien civilization," suggests the paper. Apparently, if there were a lot of naturally occurring objects like 'Oumuamua, we'd be seeing lots of them. And we're not.
Two experts from SETI weigh in. And disagree.
Two scientists from SETI (Search for Extraterrestrial Intelligence), SETI director Andrew Siemion and senior astronomer Seth Shostak, have publicly commented on the conclusions drawn by Bialy and Loeb.
Siemion termed the paper "intriguing," telling The Globe that, "Observational anomalies like we see with 'Oumuamua, combined with careful reasoning, is exactly the method through which we make new discoveries in astrophysics — including, perhaps, truly incredible ones like intelligent life beyond the Earth." However, in an email to NBC, Shostak warned, "one should not blindly accept this clever hypothesis when there is also a mundane explanation for 'Oumuamua — namely that it's a comet or asteroid from afar."
LightSail: An experiment over 35 years in the making
Step inside the unlikely friendship of a former ACLU president and an ultra-conservative Supreme Court Justice.
- Former president of the ACLU Nadine Strossen and Supreme Court Justice Antonin Scalia were unlikely friends. They debated each other at events all over the world, and because of that developed a deep and rewarding friendship – despite their immense differences.
- Scalia, a famous conservative, was invited to circles that were not his "home territory", such as the ACLU, to debate his views. Here, Strossen expresses her gratitude and respect for his commitment to the exchange of ideas.
- "It's really sad that people seem to think that if you disagree with somebody on some issues you can't be mutually respectful, you can't enjoy each other's company, you can't learn from each other and grow in yourself," says Strossen.
- The opinions expressed in this video do not necessarily reflect the views of the Charles Koch Foundation, which encourages the expression of diverse viewpoints within a culture of civil discourse and mutual respect.
Learn how to redesign your job for maximum reward.
- Broaching the question "What is my purpose?" is daunting – it's a grandiose idea, but research can make it a little more approachable if work is where you find your meaning. It turns out you can redesign your job to have maximum purpose.
- There are 3 ways people find meaning at work, what Aaron Hurst calls the three elevations of impact. About a third of the population finds meaning at an individual level, from seeing the direct impact of their work on other people. Another third of people find their purpose at an organizational level. And the last third of people find meaning at a social level.
- "What's interesting about these three elevations of impact is they enable us to find meaning in any job if we approach it the right way. And it shows how accessible purpose can be when we take responsibility for it in our work," says Hurst.
Erik Verlinde has been compared to Einstein for completely rethinking the nature of gravity.
- The Dutch physicist Erik Verlinde's hypothesis describes gravity as an "emergent" force not fundamental.
- The scientist thinks his ideas describe the universe better than existing models, without resorting to "dark matter".
- While some question his previous papers, Verlinde is reworking his ideas as a full-fledged theory.
TuSimple, an autonomous trucking company, has also engaged in test programs with the United States Postal Service and Amazon.
PAUL RATJE / Contributor
- This week, UPS announced that it's working with autonomous trucking startup TuSimple on a pilot project to deliver cargo in Arizona using self-driving trucks.
- UPS has also acquired a minority stake in TuSimple.
- TuSimple hopes its trucks will be fully autonomous — without a human driver — by late 2020, though regulatory questions remain.