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Mystery of 'Oumuamua's creation explained by study
New research proposes possible origins of the interstellar object 'Oumuamua.
- A new paper suggests a star's tidal forces could have created 'Oumuamua.
- The interstellar object 'Oumuamua was first spotted in 2017.
- The object is known for its elongated shape and unusual trajectory.
Scientists may have discovered the origins of 'Oumuamua, the first interstellar object that was spotted visiting our Solar System. The reddish, dry, and strangely-elongated 'Oumuamua, known to move in unexpected ways, has been a subject of much speculation. Some have, of course, brought up the idea it might an extraterrestrial spacecraft, possibly a probe. Now, scientists propose that tidal forces, gravitational interactions similar to those on Earth, are responsible for its existence and unusual behavior.
The cigar-shaped 'Oumuamua is 400 meters (1,300 feet) in length and was first discovered on October 19, 2017 by the Hawaii-based Panoramic Survey Telescope and Rapid Response System 1 (Pan-STARRS1). Scientists and armchair astronomers the world over have since wondered about where it came from, especially in light of factors like its acceleration away from the Sun in a trajectory that is not explainable simply by the effects of gravity.
Simulation showing the interstellar object 'Oumuamua as a collection of fragments in an elongated shape.
Credit: ZHANG Yun/background by ESO/M. Kornmesser
The new study, which was carried out by by Zhang Yun from National Astronomical Observatories of Chinese Academy of Sciences (NAOC) and Douglas N. C. Lin from University of California, Santa Cruz, says the object of mystery is natural. Clues pointing to that include the space body's colors and the lack of any radio emissions coming from it.
While scientists expect an interstellar visitor to be icy, like a comet, Oumuamua is dry and has a rocky body like an asteroid, leading the researchers to conclude that there are more such rocky objects flying in between solar systems than they previously considered.
How did such an object come into existence? Zhang and Lin believe it's a piece ripped off of another space body by a larger object. They conducted computer simulations, focusing on the example of the tidal disruption imposed by Jupiter on the comet Shoemaker-Levy 9 in 1992 to show that when a star is involved in such a fly-by, an outcome is possible that could create the elongated fragment like 'Oumuamua's.
The effects of a tidal disruption by a star on a space object.
Credit: NAOC/Y. Zhang
The researchers showed that after a space body is pulled apart by the star's tidal forces, its fragments would melt and stretch into a cigar-shaped arrangement. The resulting parts would cool off as the object moves away from the star, hardening into a crust. It is subsequently propelled farther into space.
The scientists also have an explanation for the acceleration of an object like this, proposing that the Sun's heating up of water ice under its surface can result in a release of gas that would act as a propellant.
"The tidal fragmentation scenario not only provides a way to form one single 'Oumuamua, but also accounts for the vast population of rocky interstellar objects," said Zhang. He thinks that all types of space objects, like long-period comets, debris disks, and possibly even planets, can be turned into 'Oumuamua-size bodies upon getting close to a star.
"'Oumuamua is just the tip of the iceberg," said Lin, adding "We anticipate many more interstellar visitors with similar traits will be discovered by future observation with the forthcoming Vera C. Rubin Observatory."
You can read the study in Nature Astronomy.
Was Oumuamua an alien spaceship? No. Here’s what it is.
- Astronomers spot only the 2nd interstellar object ever seen - Big Think ›
- Was Oumuamua an alien spaceship? No. Here's what it is. - Big Think ›
What is human dignity? Here's a primer, told through 200 years of great essays, lectures, and novels.
- Human dignity means that each of our lives have an unimpeachable value simply because we are human, and therefore we are deserving of a baseline level of respect.
- That baseline requires more than the absence of violence, discrimination, and authoritarianism. It means giving individuals the freedom to pursue their own happiness and purpose.
- We look at incredible writings from the last 200 years that illustrate the push for human dignity in regards to slavery, equality, communism, free speech and education.
The inherent worth of all human beings<p>Human dignity is the inherent worth of each individual human being. Recognizing human dignity means respecting human beings' special value—value that sets us apart from other animals; value that is intrinsic and cannot be lost.</p> <p>Liberalism—the broad political philosophy that organizes society around liberty, justice, and equality—is rooted in the idea of human dignity. Liberalism assumes each of our lives, plans, and preferences have some unimpeachable value, not because of any objective evaluation or contribution to a greater good, but simply because they belong to a human being. We are human, and therefore deserving of a baseline level of respect. </p> <p>Because so many of us take human dignity for granted—just a fact of our humanness—it's usually only when someone's dignity is ignored or violated that we feel compelled to talk about it. </p> <p>But human dignity means more than the absence of violence, discrimination, and authoritarianism. It means giving individuals the freedom to pursue their own happiness and purpose—a freedom that can be hampered by restrictive social institutions or the tyranny of the majority. The liberal ideal of the good society is not just peaceful but also pluralistic: It is a society in which we respect others' right to think and live differently than we do.</p>
From the 19th century to today<p>With <a href="https://books.google.com/ngrams/graph?year_start=1800&year_end=2019&content=human+dignity&corpus=26&smoothing=3&direct_url=t1%3B%2Chuman%20dignity%3B%2Cc0" target="_blank" rel="noopener noreferrer">Google Books Ngram Viewer</a>, we can chart mentions of human dignity from 1800-2019.</p><img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDg0ODU0My9vcmlnaW4ucG5nIiwiZXhwaXJlc19hdCI6MTY1MTUwMzE4MX0.bu0D_0uQuyNLyJjfRESNhu7twkJ5nxu8pQtfa1w3hZs/img.png?width=980" id="7ef38" class="rm-shortcode" data-rm-shortcode-id="9974c7bef3812fcb36858f325889e3c6" data-rm-shortcode-name="rebelmouse-image" />
American novelist, writer, playwright, poet, essayist and civil rights activist James Baldwin at his home in Saint-Paul-de-Vence, southern France, on November 6, 1979.
Credit: Ralph Gatti/AFP via Getty Images
The future of dignity<p>Around the world, people are still working toward the full and equal recognition of human dignity. Every year, new speeches and writings help us understand what dignity is—not only what it looks like when dignity is violated but also what it looks like when dignity is honored. In his posthumous essay, Congressman Lewis wrote, "When historians pick up their pens to write the story of the 21st century, let them say that it was your generation who laid down the heavy burdens of hate at last and that peace finally triumphed over violence, aggression and war."</p> <p>The more we talk about human dignity, the better we understand it. And the sooner we can make progress toward a shared vision of peace, freedom, and mutual respect for all. </p>
Scientists find that bursts of gamma rays may exceed the speed of light and cause time-reversibility.
- Astrophysicists propose that gamma-ray bursts may exceed the speed of light.
- The superluminal jets may also be responsible for time-reversibility.
- The finding doesn't go against Einstein's theory because this effect happens in the jet medium not a vacuum.
Jet bursting out of a blazar. Black-hole-powered galaxies called blazars are the most common sources detected by NASA's Fermi Gamma-ray Space Telescope.
Cosmic death beams: Understanding gamma ray bursts<div class="rm-shortcode" data-media_id="cu2knVEk" data-player_id="FvQKszTI" data-rm-shortcode-id="c6cfd20fdf31c82cb206ade8ce21ba3f"> <div id="botr_cu2knVEk_FvQKszTI_div" class="jwplayer-media" data-jwplayer-video-src="https://content.jwplatform.com/players/cu2knVEk-FvQKszTI.js"> <img src="https://cdn.jwplayer.com/thumbs/cu2knVEk-1920.jpg" class="jwplayer-media-preview" /> </div> <script src="https://content.jwplatform.com/players/cu2knVEk-FvQKszTI.js"></script> </div>
Researchers dramatically improve the accuracy of a number that connects fundamental forces.
- A team of physicists carried out experiments to determine the precise value of the fine-structure constant.
- This pure number describes the strength of the electromagnetic forces between elementary particles.
- The scientists improved the accuracy of this measurement by 2.5 times.
The process for measuring the fine-structure constant involved a beam of light from a laser that caused an atom to recoil. The red and blue colors indicate the light wave's peaks and troughs, respectively.
Scientists at Washington University are patenting a new electrolyzer designed for frigid Martian water.
- Mars explorers will need more oxygen and hydrogen than they can carry to the Red Planet.
- Martian water may be able to provide these elements, but it is extremely salty water.
- The new method can pull oxygen and hydrogen for breathing and fuel from Martian brine.