Physicists at MIT Shave Estimate of Mass of Neutrino “Ghost Particle” in Half - SciTechDaily - Canadanewsmedia
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Physicists at MIT Shave Estimate of Mass of Neutrino “Ghost Particle” in Half – SciTechDaily

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KATRIN’s spectrometer, shown here, precisely measures the energy of electrons emitted in the decay of tritium, which has helped scientists come closer to pinning down the mass of the ghost-like neutrino. Credit: The KATRIN Collaboration

Joseph Formaggio explains the discovery that the ghostly particle must be no more than 1 electronvolt, half as massive as previously thought.

An international team of scientists, including researchers at MIT, has come closer to pinning down the mass of the elusive neutrino. These ghost-like particles permeate the universe and yet are thought to be nearly massless, streaming by the millions through our bodies while leaving barely any physical trace.

The researchers have determined that the mass of the neutrino should be no more than 1 electron volt. Scientists previously estimated the upper limit of the neutrino’s mass to be around 2 electron volts, so this new estimate shaves down the neutrino’s mass range by more than half.

The new estimate was determined based on data taken by KATRIN, the Karlsruhe Tritium Neutrino Experiment, at the Karlsruhe Institute of Technology in Germany, and reported at the 2019 Conference on Astroparticle and Underground Physics last week. The experiment triggers tritium gas to decay, which in turn releases neutrinos, along with electrons. While the neutrinos are quick to dissipate, KATRIN’s sequence of magnets directs tritium’s electrons into the heart of the experiment — a giant 200-ton spectrometer, where the electrons’ mass and energy can be measured, and from there, researchers can calculate the mass of the corresponding neutrinos.

Joseph Formaggio, professor of physics at MIT, is a leading member of the KATRIN experimental group, and spoke with MIT News about the new estimate and the road ahead in the neutrino search.

Q: The neutrino, based on KATRIN’s findings, can’t be more massive than 1 electron volt. Put this context for us: How light is this, and how big a deal is it that the neutrino’s maximum mass could be half of what people previously thought?

A: Well, that’s somewhat of a difficult question, since people (myself included) don’t really have an intuitive sense of what the mass is of any particle, but let’s try. Consider something very small, like a virus. Each virus is made up of roughly 10 million protons. Each proton weighs about 2,000 times more than each electron inside that virus. And what our results showed is that the neutrino has a mass less than 1/ 500,000 of a single electron!

Let me put it another way. In each cubic centimeter of space around you, there are about 300 neutrinos zipping through. These are remnants of the early universe, just after the Big Bang. If you added up all the neutrinos residing inside the sun, you’d get about a kilogram or less. So, yeah, it’s small.

Q: What went into determining this new mass limit for the neutrino, and what was MIT’s role in the search?

A: This new mass limit comes from studying the radioactive decay of tritium, an isotope of hydrogen. When tritium decays, it produces a helium-3 ion, an electron, and an antineutrino. We actually never see the antineutrino, however; the electron carries information about the neutrino’s mass. By studying the energy distribution of the electrons ejected at the highest energies allowed, we can deduce the mass of the neutrino, thanks to Einstein’s equation, E=mc2.

However, studying those high-energy electrons is very difficult. For one thing, all the information about the neutrino is embedded in a tiny fraction of the spectrum — less than 1 billionth of decays are of use for this measurement. So, we need a lot of tritium inventory. We also need to measure the energy of those electrons very, very precisely. This is why the KATRIN experiment is so tricky to build. Our very first measurement presented today is the culmination of almost two decades of hard work and planning.

MIT joined the KATRIN experiment when I came to Boston in 2005. Our group helped develop the simulation tools to understand the response of our detector to high precision. More recently, we have been involved in developing tools to analyze the data collected by the experiment.

Q: Why does the mass of a neutrino matter, and what will it take to zero in on its exact mass?

A: The fact that neutrinos have any mass at all was a surprise to many physicists. Our earlier models predicted that the neutrino should have exactly zero mass, an assumption dispelled by the discovery that neutrinos oscillate between different types. That means we do not really understand the mechanism responsible for neutrino masses, and it is likely to be very different than how other particles attain mass. Also, our universe is filled with primordial neutrinos from the Big Bang. Even a tiny mass has a significant impact on the structure and evolution of the universe because they are so aplenty.

This measurement represents just the beginning of KATRIN’s measurement. With just about one month of data, we were able to improve previous experimental limits by a factor of two. Over the next few years, these limits will steadily improve, hopefully resulting in a positive signal (rather than just a limit). There are also a number of other direct neutrino mass experiments on the horizon that are also competing to reach greater sensitivity, and with it, discovery!

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Billionaire Bezos unveils plans to land humans on Moon, with a little help from some old friends – The Register

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Blue Origin and industry vets eye a slice of NASA’s lunar lander largesse

Richest person in the world, Jeff Bezos, yesterday pitched NASA a team mostly made up of the usual suspects to build a lunar lander for the agency’s ambitious 2024 boots-on-Moon goal.

Speaking at the International Astronautical Congress in Washington, Bezos announced the “national team”, of which his Blue Origin would be the prime contractor (naturally). The members consist of Lockheed Martin for the Ascent Stage, Northrop Grumman for the Transfer Element and Draper providing the guidance and navigation systems.

“We could not ask for better partners,” intoned the billionaire, which is fair enough. After all, elements of all the companies in the team-up worked on the Apollo program back in the day (although those engineers will have long been put out to pasture.)

The Transfer Element will guide the stack from lunar orbit to close to the Moon, from whence the Descent Element will conduct a powered descent. Lockheed Martin’s ascent module will then send the freshly minted Moonwalkers back into space.

Blue Origin will also be building the descent element of the lander, which uses the company’s BE-7 engine. The powerplant, Bezos said, is fuelled by liquid hydrogen and oxygen and as well being “highly throttleable” and developing 10,000 pounds of thrust.

The BE-7, of course, has yet to actually leave the test stand. Bezos told the audience that to date, the company had managed 13 minutes of test time, including a three-minute continuous firing.

That same engine, Bezos added, would be used by Northrop Grumman in the transfer element of the lunar lander stack.

Bezos unveiled the Blue Moon lander back in May and the announcement of the National Team is an indicator that it will take more than one company to meet the 2024 goal. It will also reassure those within NASA nervous about flinging cash at a company that has yet to even make Earth orbit, let alone do anything in deep space.

And NASA has lots of experience in giving money to Lockheed Martin and Northrop Grumman after all.

Grumman, of course, built the original Apollo Lunar Module back in NASA’s glory days while Draper provided the guidance systems for the Moon missions.

These days, Northrop Grumman provides NASA with ISS cargo services and is working on both the boosters for the eternally-delayed Space Launch System and the habitat for the agency’s Lunar Gateway.

Draper has continued to work on precision guidance, although there is a delightful hole to tumble down in researching the Apollo guidance units, particularly efforts to fire up the old things once more. Naturally, the hand-woven circuitry of the Apollo era won’t feature this time around.

NASA is due to select two contractor teams in late 2020 to actually build the lander, having asked for proposals (and deleted certain reusability requirements in the rush to 2024). ®

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Bezos's Blue Origin partners with Lockheed, others on moon lander – Financial Post

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WASHINGTON — U.S. billionaire Jeff Bezos said on Tuesday his space company Blue Origin has signed agreements with Lockheed Martin Corp, Northrop Grumman Corp and research and development organization Draper for development of its lunar lander designed to help NASA put humans on the moon by 2024.

Blue Origin’s so-called Blue Moon lunar lander, unveiled by Bezos in May, is in development and sits at the center of the space company’s ambition to ferry humans into deep space and land key contracts from the U.S. space agency for space exploration.

“I’m excited to announce that we put together a national team to go back to the moon,” Bezos, founder and CEO of online retail giant Amazon, said at the International Astronautical Congress.

The four companies, with Blue Origin as the lead contractor, plan to submit a proposal for the lander to NASA under its Artemis lunar program, an accelerated mission to the moon kickstarted in March by U.S. Vice President Mike Pence.

Bezos called the partnerships a “national team” whose history in space exploration fits the Blue Moon’s mission. Lockheed is separately developing the moon-bound astronaut capsule named Orion. Northrop helped NASA build the Apollo lunar landers in the 1960s. Draper, a not-for-profit research and development organization, built NASA’s navigation computers for Apollo lunar landers. (Reporting by Joey Roulette; Editing by Sandra Maler)

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A giant full beaver moon set to dazzle Metro Vancouver skies – Vancouver Courier

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While it is getting darker earlier in Metro Vancouver, this month’s full beaver moon promises to illuminate the night sky.

The November full moon is thought to have derived its funny name because it occurred during the optimal time to trap the furry creatures. In fact, both colonial Americans as well as the Algonquin tribes referred to it as such.

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“Why this name? Back then, this was the month to set beaver traps before the swamps froze, to ensure a supply of warm winter furs,” reports Farmer’s Almanac.

While it is commonly known as the beaver moon, it was also called the Full Frost Moon by other North American Tribes.

According to the Old Farmer’s Almanac, the moon will be fullest during the day on Tuesday, Nov. 12. However, Vancouver stargazers will still be able to see the nearly-full moon in all her celestial glory the night before (Nov. 11) as well as later that night (Nov. 12).

What’s more, this full moon casts long, hauntingly beautiful shadows in the Northern Hemisphere. They are similar to those cast by the midday summer sun, as the moon is extremely high in the sky during this time.

Stargazers should opt to travel as far away from city lights as possible in order to avoid light pollution that will obscure the clarity of heavenly bodies. While this works best the in more remote places, anywhere that has a higher elevation will also provide more ideal viewing conditions.

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