A particle shower detected by the IceCube Neutrino Observatory at the very high energy of the Glashow resonance demonstrates its potential for the study of high-energy particle physics and astrophysics.
5 january 2020.
This paper proposes the use of Flower Constellation (FC) theory to facilitate the design of a Low Earth Orbit (LEO) slotting system to avoid collisions between compliant satellites and optimize the available space. Specifically, it proposes the use of concentric orbital shells of admissible “slots” with stacked intersecting orbits that preserve a minimum separation distance between satellites at all times. The problem is formulated in mathematical terms and three approaches are explored: random constellations, single 2D Lattice Flower Constellations (2D-LFCs), and unions of 2D-LFCs. Each approach is evaluated in terms of several metrics including capacity, Earth coverage, orbits per shell, and symmetries. In particular, capacity is evaluated for various inclinations and other parameters. Next, a rough estimate for the capacity of LEO is generated subject to certain minimum separation and station-keeping assumptions and several trade-offs are identified to guide policy-makers interested in the adoption of a LEO slotting scheme for space traffic management.
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Tyson’s latest book “Cosmic Queries” covers the gamut from early Earth’s pond scum to potential multiverses to out-of-the-box ideas about the potential that we live in a false vacuum cosmos.
After the past year’s pandemic pall, it’s nice to be reminded that we remain inextricably connected to the cosmos beyond Earth’s atmosphere. In the new book “Cosmic Queries: StarTalk’s Guide to Who We Are, How We Got Here, and Where We’re Going,” astrophysicist and StarTalk podcast host Neil DeGrasse Tyson, along with George Mason University physics professor James Trefil, clearly remind us of our cosmic legacy.
Tyson, Director of New York City’s Hayden Planetarium at the American Museum of Natural History, is well known for his ability to provoke the public into thinking harder about our place in the cosmos. And “Cosmic Queries” does just that. Tyson and Trefil succinctly lead the reader through almost every aspect of cosmic history while addressing age-old questions with new verve.
Continue reading “Provocative New Neil DeGrasse Tyson Book Highlights Little-Known Cosmic Tidbits” »
If you want to build a fully functional nanosized robot, you need to incorporate a host of capabilities, from complicated electronic circuits and photovoltaics to sensors and antennas.
But just as importantly, if you want your robot to move, you need it to be able to bend.
Continue reading “Nanotech scientists create world’s smallest origami bird” »
Sam Altman, the co-founder and president of San Francisco-headquartered tech nonprofit OpenAI, says AI will generate enough wealth to pay each adult $13500 a year.
Today on the Science Talk podcast, Noam Slonim speaks to Scientific American about an impressive feat of computer engineering: an AI-powered autonomous system that can engage in complex debate with humans over issues ranging from subsidizing preschool and the merit of space exploration to the pros and cons of genetic engineering.
In a new Nature paper, Slonim and colleagues show that across 80 debate topics, Project Debater’s computational argument technology has performed very decently—with a human audience being the judge of that. “However, it is still somewhat inferior on average to the results obtained by expert human debaters,” says Slonim.
Continue reading “AI Can Now Debate with Humans and Sometimes Convince Them, Too” »
‘Skybrators’ generate clean energy without environmental impact of large windfarms, say green pioneers.
“The research is part of an explosion of new techniques and ideas for studying early development. Today, in the same issue of Nature, two other research groups are reporting a leap forward in creating ”artificial” human embryos.
Those teams managed to coax ordinary skin cells and stem cells to self-assemble into look-alike early human embryos they call ”blastoids,” which they grew for about 10 days in the lab. Several kinds of artificial models of embryos have been described before, but those described today are among the most complete, because they possess the cells needed to form a placenta. That means they are a step closer to being viable human embryos that could develop further, even until birth.
Scientists say that they would never try to establish a pregnancy with artificial embryos—an act that would be forbidden today in most countries.
Continue reading “A mouse embryo has been grown in an artificial womb—humans could be next” »
Dr James Desmond, DVM, Co-Founder, Liberia Chimpanzee Rescue & Protection (LCRP), discussing his work at LCRP, as well as his zoonotic disease surveillance work with EcoHealth.
Liberia Chimpanzee Rescue & Protection (LCRP — https://www.liberiachimpanzeerescue.org/) is the first and only chimpanzee sanctuary and conservation center in Liberia rescuing chimpanzees who are victims of the illegal bush meat and pet trades. The organization has over 40 orphaned chimpanzees, nearly all under the age of five, currently under their care.
