Gravitational Wave Astronomy: When Stars Die, New Sciences Are Born
Get ready for a decade of scientific revelations. Thanks to gravity waves, we have a completely new way to explore the universe.
Alex Filippenko is the Richard & Rhoda Goldman Distinguished Professor in the Physical Sciences. His accomplishments, documented in more than 800 research papers, have been recognized by several major prizes, including a share of both the Gruber Cosmology Prize (2007) and the Breakthrough Prize in Fundamental Physics (2015). One of the world's most highly cited astronomers, he is an elected member of the National Academy of Sciences (2009) and the American Academy of Arts and Sciences (2015). He has won the most prestigious teaching awards at UC Berkeley and has also been voted the "Best Professor" on campus a record 9 times. Selected in 2006 as the Carnegie/CASE National Professor of the Year among doctoral institutions, he has also received the Richard H. Emmons Award for undergraduate teaching (2010). He produced five astronomy video courses with "The Great Courses" (see below), coauthored an award-winning astronomy textbook, and appears in more than 100 TV documentaries, including about 50 episodes of "The Universe" series. He has given nearly 1000 public lectures or other presentations, was awarded the 2004 Carl Sagan Prize for Science Popularization, and received the prestigious Hertz Foundation fellowship for his PhD studies at The California Institute of Technology.
Filippenko is the only person who was a member of both the Supernova Cosmology Project and the High-z Supernova Search Team, which used observations of extragalactic supernovae to discover the accelerating universe and its implied existence of dark energy. The discovery was voted the top science breakthrough of 1998 by Science magazine] and resulted in the 2011 Nobel prize for physics being awarded to the leaders of the two project teams.
Filippenko developed and runs the Katzman Automatic Imaging Telescope (KAIT), a fully robotic telescope which conducts the Lick Observatory Supernova Search (LOSS), the most successful nearby supernova search. He is also a member of the Nuker Team which uses the Hubble space telescope to examine supermassive black holes and determined the relationship between a galaxy's central black hole's mass and velocity dispersion. The Thompson-Reuters "incites" index ranked Filippenko as the most cited researcher in space science for the ten-year period between 1996 and 2006
Alex Filippenko: One of the most exciting discoveries in all of science in the past year—and one in which there will be a lot of progress in the next five years—is the discovery of gravitational waves: ripples in the actual fabric of space time produced when, for example, two massive stars or black holes merge into one.
LIGO, the Laser Interferometer Gravitational-Wave Observatory, in September 2015 detected a signal, which, after months of processing, the scientists became convinced was the signature of two black holes merging together 1.3 billion light years away. Now this is absolutely magnificent, because it's a key prediction of Einstein's general theory of relativity, his theory of gravity.
It predicts that when two massive, especially dense objects merge together, the dimples that each of them individually form in the shape of space sort of form a spiral pattern that goes outward— a little bit like a water wave when you toss a ball onto a swimming pool. And that wave carries energy and it's extremely difficult to detect, but scientists last year detected it and announced that result, and I was just blown away. Two black holes each having a mass of about 30 times the mass of the sun merging together. It's just fantastic.
And a couple of more events of that sort have been detected since then black holes merging together. As the scientists and engineers perfect this technique even more, they will be able to study merging neutron stars and other kinds of astrophysical objects.
And this will allow us to study them in a way that's simply not possible with light with electromagnetic radiation, because gravitational waves are not a form of electric and magnetic fields oscillating in space, instead they're an actual ripple, a little thingy going out in the shape of space, and with the passage of time showing that Einstein's idea that massive objects really do form a distinct dimple, which then forms a ripple of two of these things merge or if one of them explodes or something like that.
This theory really is correct, and it took a century to show that that's true. Now, the precision of the measurement is just mind-boggling. It's by far the most precise measurement ever made by anyone. They had to measure the distances of a length of, well I don't want to get into the details now, but of their device—Their device had two four-kilometer length arms and they had to measure the length of those arms to a precision of 1/1000th of a proton.
Now a proton is yay big, and I exaggerate a lot. So this four-kilometer length arm changed in length a tiny bit as this gravitational wave was passing through, and they had to measure this change of 1/1000th of a proton. It's as though you were measuring the distance of the nearest star, which is 4.2 light years or 40 million million kilometers (40 trillion kilometers), to the width of a human hair. That's the kind of precision we're talking about.
Imagine measuring the distance of the nearest star to a precision of the width of a human hair. It's just incredible.
Even though the discovery of gravitational waves was first made in September of 2015 and announced to the world in February of 2016, it's a very young field. There will be more such detections, and we're just beginning to explore the universe in a way where we're completely blind with electromagnetic waves, with light. So I anticipate huge discoveries in the next five to ten years in the field of gravitational wave astronomy.
Alex Filippenko is a Hertz Foundation Fellow and recipient of the prestigious Hertz Foundation Grant for graduate study in the applications of the physical, biological and engineering sciences. When the discovery of gravitational waves was announced in February 2016, Filippenko was awed. The researchers at LIGO (Laser Interferometer Gravitational-Wave Observatory) managed to prove a key prediction of Einstein's general theory of relativity: his theory of gravity. Here, Filippenko explains the mind-boggling way they did it, and the scope of discoveries that this hyper-precise technology will reveal to us over the next decade. With the support of the Fannie and John Hertz Foundation, Filippenko pursued a PhD in astronomy at the California Institute of Technology.
The Hertz Foundation mission is to provide unique financial and fellowship support to the nation's most remarkable PhD students in the hard sciences. Hertz Fellowships are among the most prestigious in the world, and the foundation has invested over $200 million in Hertz Fellows since 1963 (present value) and supported over 1,100 brilliant and creative young scientists, who have gone on to become Nobel laureates, high-ranking military personnel, astronauts, inventors, Silicon Valley leaders, and tenured university professors. For more information, visit hertzfoundation.org.
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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>
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.
The WashU electrolyzer<iframe src='https://mars.nasa.gov/layout/embed/model/?s=6' width='800' height='450' scrolling='no' frameborder='0' allowfullscreen></iframe><p>The WashU electrolyzer—it has no snappy acronym yet—will not be the first device capable of extracting oxygen from Martian water. That honor goes to the Mars Oxygen In-Situ Resource Utilization Experiment, or <a href="https://mars.nasa.gov/mars2020/spacecraft/instruments/moxie/" target="_blank">MOXIE</a>, which is en route to Mars onboard NASA's <a href="https://mars.nasa.gov/mars2020/" target="_blank">Perseverance</a> rover. The rover was launched on July 30, 2020. It will arrive on February 18, 2021, and will perform high-temperature <a href="https://en.wikipedia.org/wiki/Electrolysis_of_water" target="_blank">electrolysis</a> to extract pure oxygen, but no hydrogen.</p><p>In addition to being able to capture hydrogen, the WashU system can even do a better job with oxygen than MOXIE can, extracting 25 times as much from the same amount of water.</p><p>The new system has no problem with Mars' magnesium perchlorate-laced water. On the contrary, the researchers say it ultimately makes their system work better since such high concentrations of salt keep water from freezing on such a cold a planet by lowering the liquid's freezing temperature to -60 °C. He adds it may "also improve the performance of the electrolyzer system by lowering the electrical resistance."</p><p>Cold itself is no issue for the WashU system. It's been tested in a sub-zero (-33 ⁰F, or -36 ⁰C) environment that simulates Mars'.</p><p>"Our novel brine electrolyzer incorporates a lead <a href="https://www.sciencedirect.com/science/article/abs/pii/S0926337318311299" target="_blank">ruthenate pyrochlore</a> <a href="https://en.wikipedia.org/wiki/Anode" target="_blank" rel="noopener noreferrer">anode</a> developed by our team in conjunction with a platinum on carbon <a href="https://en.wikipedia.org/wiki/Cathode" target="_blank">cathode</a>," explains Ramani. He adds, "These carefully designed components coupled with the optimal use of traditional electrochemical engineering principles has yielded this high performance."</p>
Back home<p>"This technology is equally useful on Earth where it opens up the oceans as a viable oxygen and fuel source," Ramani notes. His colleagues forsee potential applications such as producing oxygen in deep-sea habitats with ample water available, such as underwater research facilities and submarines.</p><p>The study's joint first author Pralay Gayen says that "having demonstrated these electrolyzers under demanding Martian conditions, we intend to also deploy them under much milder conditions on Earth to utilize brackish or salt water feeds to produce hydrogen and oxygen, for example, through seawater electrolysis."</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>
Pfizer's vaccine needs to be kept at -100°F until it's administered. Can caregivers deliver?
- Fair distribution of the Moderna and Pfizer vaccines is especially challenging because they need to be stored at extremely cold temperatures.
- Back in 2018, the WHO reported that over half of all vaccines are wasted worldwide due to lack of cold storage, and they were only talking about vaccines that need to be chilled or kept at standard freezer temperatures.
- Real-time logistics data, location tracking, and information about movements are crucial to track shipment progress, product temperature and other conditions.