Research: Most massive neutron star ever detected, almost too massive to exist - Tdnews - Canadanewsmedia
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Research: Most massive neutron star ever detected, almost too massive to exist – Tdnews

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Neutron stars — the compressed remains of massive stars gone supernova — are the densest “normal” objects in the known universe. (Black holes are technically denser, but far from normal.) Just a single sugar-cube worth of neutron-star material would weigh 100 million tons here on Earth, or about the same as the entire human population. Though astronomers and physicists have studied and marveled at these objects for decades, many mysteries remain about the nature of their interiors: Do crushed neutrons become “superfluid” and flow freely? Do they breakdown into a soup of subatomic quarks or other exotic particles? What is the tipping point when gravity wins out over matter and forms a black hole?

A team of astronomers using the National Science Foundation’s (NSF) Green Bank Telescope (GBT) has brought us closer to finding the answers.

The researchers, members of the NANOGrav Physics Frontiers Center, discovered that a rapidly rotating millisecond pulsar, called J0740+6620, is the most massive neutron star ever measured, packing 2.17 times the mass of our Sun into a sphere only 30 kilometers across. This measurement approaches the limits of how massive and compact a single object can become without crushing itself down into a black hole. Recent work involving gravitational waves observed from colliding neutron stars by LIGO suggests that 2.17 solar masses might be very near that limit.

“Neutron stars are as mysterious as they are fascinating,” said Thankful Cromartie, a graduate student at the University of Virginia and Grote Reber pre-doctoral fellow at the National Radio Astronomy Observatory in Charlottesville, Virginia. “These city-sized objects are essentially ginormous atomic nuclei. They are so massive that their interiors take on weird properties. Finding the maximum mass that physics and nature will allow can teach us a great deal about this otherwise inaccessible realm in astrophysics.”

Pulsars get their name because of the twin beams of radio waves they emit from their magnetic poles. These beams sweep across space in a lighthouse-like fashion. Some rotate hundreds of times each second. Since pulsars spin with such phenomenal speed and regularity, astronomers can use them as the cosmic equivalent of atomic clocks. Such precise timekeeping helps astronomers study the nature of spacetime, measure the masses of stellar objects, and improve their understanding of general relativity.

In the case of this binary system, which is nearly edge-on in relation to Earth, this cosmic precision provided a pathway for astronomers to calculate the mass of the two stars.

As the ticking pulsar passes behind its white dwarf companion, there is a subtle (on the order of 10 millionths of a second) delay in the arrival time of the signals. This phenomenon is known as “Shapiro Delay.” In essence, gravity from the white dwarf star slightly warps the space surrounding it, in accordance with Einstein’s general theory of relativity. This warping means the pulses from the rotating neutron star have to travel just a little bit farther as they wend their way around the distortions of spacetime caused by the white dwarf.

Astronomers can use the amount of that delay to calculate the mass of the white dwarf. Once the mass of one of the co-orbiting bodies is known, it is a relatively straightforward process to accurately determine the mass of the other.

Cromartie is the principal author on a paper accepted for publication in Nature Astronomy. The GBT observations were research related to her doctoral thesis, which proposed observing this system at two special points in their mutual orbits to accurately calculate the mass of the neutron star.

“The orientation of this binary star system created a fantastic cosmic laboratory,” said Scott Ransom, an astronomer at NRAO and coauthor on the paper. “Neutron stars have this tipping point where their interior densities get so extreme that the force of gravity overwhelms even the ability of neutrons to resist further collapse. Each “most massive” neutron star we find brings us closer to identifying that tipping point and helping us to understand the physics of matter at these mindboggling densities.”

These observation were also part of a larger observing campaign known as NANOGrav, short for the North American Nanohertz Observatory for Gravitational Waves, which is a Physics Frontiers Center funded by the NSF.

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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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