Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: nuclear energy – Page 45

A study of neutrinos from the Sun has measured the signal from the so-called CNO cycle, offering a direct measure of the elemental abundances in the Sun’s core.

Solar neutrinos are copiously produced by hydrogen fusion reactions in the Sun’s core. Therefore, they are the direct evidence that the Sun is powered by nuclear reactions. Measurements of solar neutrinos have provided information about the temperature and density of the solar interior, but uncertainties remain about the chemical ingredients. Now the Borexino Collaboration reports a new measurement of the neutrino flux produced by the so-called CNO hydrogen burning cycle in the Sun [1]. This cycle—which requires the presence of carbon ©, nitrogen (N), and oxygen (O)—produces neutrinos that carry enormous diagnostic power relating to the properties of the solar interior. By measuring these neutrinos, the collaboration provides a precious piece of information about the elemental makeup of the Sun, bringing us closer to resolving a controversy that has plagued solar physics for over 20 years [2].

Stars spend about 90% of their lifetimes fusing hydrogen into helium, producing two neutrinos in the process. The pp chain—or proton–proton chain—and CNO cycle are the two fundamental modes by which stellar fusion occurs. Whether a star is dominated by the pp chain or the CNO cycle depends on its core temperature, which is primarily determined by the mass of the star. In the Sun and similar low-mass stars, the pp chain generates almost all the nuclear energy; the CNO cycle is the main power source for more massive stars. The pp chain is a series of nuclear reactions that require no additional nuclei besides hydrogen as fuel. By contrast, the CNO cycle relies on the presence of C, N, and O nuclei as catalysts in the production of helium (Fig. 1). In the Sun, this catalytic process introduces a linear dependence between the amount of C, N, and O and the flux of CNO neutrinos. Thus, CNO neutrinos are a powerful tool for probing the chemical composition in the Sun’s core.

Read more | >

How could we one day travel between the stars with real physics? Perhaps the greatest challenge to interstellar flight is energetics — it takes vast amounts of energy to accelerate even small ships to 20% the speed of light. But what if we could steal that energy from where? Perhaps even a black hole. Enter the “halo drive”, a video by Prof David Kipping based on his new peer-reviewed research paper on the subject.

This video is based on research conducted at the Cool Worlds Lab at Columbia University, New York. You can now support our research program directly here: https://www.coolworldslab.com/support.

Further reading and resources:
► Kipping, David (2018), “The Halo Drive: Fuel Free Relativistic Propulsion of Large Mases via Recycled Boomerang Photons”, JBIS, 71458: https://arxiv.org/abs/1903.03423
► Dyson, Freeman (1963), “Gravitational Machines”, in A.G.W. Cameron, ed., Interstellar Communication, New York Benjamin Press: https://www.ifa.hawaii.edu/~barnes/ast242_s14/Dyson_Machines.pdf.
► Breakthrough Starshot homepage: https://breakthroughinitiatives.org/initiative/3
► Our Cool Worlds video giving some background on Breakthrough Starshot: https://youtu.be/Ksb6Vh0BT_E
► Our Cool Worlds video on relativistic moving mirrors: https://youtu.be/msK9d9k6K0E
► Our Cool Worlds video on mirror distortion effects: https://youtu.be/1iNA-GTocI0
► Columbia University Department of Astronomy: http://www.astro.columbia.edu.
► Cool Worlds Lab website: http://coolworlds.astro.columbia.edu.

There’s an error in the video at around 8:30, 2 trillion joules is the cumulative energy output of a typical nuclear power station after 2000 seconds, not 20 days.

Continue reading “The Halo Drive” | >

The U.S. Department of Energy (DOE) has today confirmed the achievement of “fusion ignition” at Lawrence Livermore National Laboratory (LLNL) – a major scientific breakthrough, many decades in the making, which could pave the way to near-limitless clean power.

On 5th December, a team at LLNL’s National Ignition Facility (NIF) conducted the first controlled experiment in history to reach this milestone, also known as scientific energy breakeven, meaning it produced more energy from fusion than the laser energy used to drive it. This first-of-its-kind feat will provide invaluable insights into the fusion energy process, which scientists have been attempting to develop for nearly a century.

Inside the target chamber of LLNL’s National Ignition Facility, 192 laser beams delivered more than 2 million joules of ultraviolet energy to a tiny fuel pellet to create the fusion ignition. These lasers heated the capsule to 100,000,000°C – more than six times hotter than the Sun’s core, and compressed it to more than 100 billion times the pressure of Earth’s atmosphere. Under these unimaginable forces, the capsule would have imploded on itself, forcing its hydrogen atoms to fuse and release energy.

Read more | >

Researchers at the Lawrence Livermore National Laboratory claim to have achieved the seemingly impossible: generate more energy with a fusion reaction than they put into it, potentially paving the way for a truly environmentally friendly and safe source of power.

Their experiment, which involved using the “world’s largest and highest energy laser system” at Livermore’s National Ignition Facility to blast light at small capsules of deuterium-tritium fuel, generated 20 percent more energy than the amount required to power the system.

Despite the modest energy output — the system generated enough power to boil around two to three kettles — the researchers are boldly predicting that it could represent a major turning point in the quest to turn fusion energy into a reality.

Read more | >

This new breakthrough opens the door to limitless clean energy.

The time has finally come. Scientists at the Lawrence Livermore National Laboratory (LLNL) are the first in the world to demonstrate net energy production from nuclear fusion.

In other words, theirs was the first ever nuclear fusion experiment to produce more energy than was required to run the experiment in the first place.

Researchers achieved the milestone, also known as fusion ignition, at LLNL’s National Ignition Facility (NIF) during a controlled fusion experiment last Monday, Dec. 5, according to a statement from the US Department of Energy (DOE). They waited for peer-review results before revealing the results to the world.

Continue reading “Finally! Nuclear fusion scientists achieved net energy production in a historic first” | >

WASHINGTON, Dec 12 (Reuters) — The U.S. Department of Energy on Tuesday will announce that scientists at a national lab have made a breakthrough on fusion, the process that powers the sun and stars that one day could provide a cheap source of electricity, three sources with knowledge of the matter said.

The scientists at Lawrence Livermore National Laboratory in California have achieved a net energy gain for the first time, in a fusion experiment using lasers, one of the people said.

While the results are a milestone in a scientific quest that has been developing since at least the 1930s, the ratio of energy going into the reaction at Livermore to getting energy out of it needs to be about 100 times bigger to create a process producing commercial amounts of electricity, one of the sources said.

Read more | >

Overnight, news broke that the National Ignition Facility, a U.S. government research lab, was the first to achieve net-positive nuclear fusion. When lasers hit the tiny fuel pellet, it created an explosion that released more energy than the lasers delivered.

For decades, fusion power has been just around the corner. Is this the moment we’ve all been waiting for?

Maybe.

Read more | >