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6 billion planets like Earth? Scientists make stunning estimate
Astronomers propose new estimate of Earth-like planets in the Milky Way galaxy.
- Astronomers make new analysis based on data from NASA's Kepler space telescope.
- The researchers estimate there may be as many as six billion Earth-like planets in our galaxy alone.
- The scientists looked for planets that would be able to host life.
Maybe you think one Earth is enough. But what if there were billions? Researchers make a new estimate that the number of Earth-like planets in our Milky Way galaxy can reach us high as 6 billion.
Astronomers at the University of British Columbia (UBC) analyzed data from NASA's Kepler mission to reach the stunning conclusion. The information on 200,000 stars was gathered by the Kepler planet-hunting spacecraft from 2009 to 2018.
The criteria used by the scientists for selecting such a planet maintained it had to be rocky, about the same size as Earth, and orbiting a star like our Sun. This planet also had to be in the habitable zone of its star, where the conditions would be just right to potentially allow for water and life.
UBC researcher Michelle Kunimoto, who co-authored the new study, and previously discovered 17 new planets ("exoplanets") outside our Solar System, said their calculations "place an upper limit of 0.18 Earth-like planets per G-type star." In other words, that's about 5 planets per Sun.
The study's co-author UBC astronomer Jaymie Matthews put this from another perspective, explaining that "Our Milky Way has as many as 400 billion stars, with seven per cent of them being G-type. That means less than six billion stars may have Earth-like planets in our Galaxy."
To conduct the study, Kunimoto utilized a technique known as 'forward modelling,' which allowed her to overcome the issue that Earth-like planets are hard to spot on account of being small and orbiting far from their star.
Legacy of NASA’s Kepler Space Telescope
"I started by simulating the full population of exoplanets around the stars Kepler searched," expounded the researcher in UBC's press release. "I marked each planet as 'detected' or 'missed' depending on how likely it was my planet search algorithm would have found them. Then, I compared the detected planets to my actual catalogue of planets. If the simulation produced a close match, then the initial population was likely a good representation of the actual population of planets orbiting those stars."
While the scientists came up with an impressive number of possible Earths, this likely doesn't mean that's how many such planets there are and if they would have life like ours. But this new estimate definitely expands the possibility that similar planets are out there.
Check out the new study in The Astronomical Journal.
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.