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Metrologists have launched the new definition of a "kilogram" based on the Planck Constant on World Metrology Day. Metrologists have launched the new definition of a "kilogram" based on the Planck Constant on World Metrology Day.

Science

Metrologists Launched The New Definition Of A “Kilogram” On World Metrology Day

[bctt tweet=”Here’s the new definition of Kilograms that you should take note now.” username=”Z6Mag”]

Happy Metrology Day! Photo: Chie | Flickr | CC BY 2.0

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It’s official; the kilogram as we know it is no longer the same. As of today, the 130-year definition of the unit of measurement “kilogram” has already been retired and has been redefined to follow a more constant and precise definition.

The change was voted upon in the General Conference on Weights and Measures in Versailles last year, and the organization is implementing the more accurate definition of a “kilogram” today, May 20, 2019 – the World Metrology Day.

Metrologists – the scientists who study measurement systems – argue that the existing definition of a kilogram is no longer accurate and they need a new standard to follow because the precision of measurements is essential in almost all industries.

Of the seven base units of the International System of Units (SI), four are not currently based on the constants of physics: the ampere (current), Kelvin (temperature), mole (amount of substance) and kilogram (mass).

“The idea,” explained Emeritus Director of the International Bureau of Weights and Measures (BIPM) Terry Quinn to ScienceAlert, “is that by having all the units based on the constants of physics, they are by definition stable and unaltering in the future, and universally accessible everywhere.”

For example, a meter is determined by the distance light travels in a vacuum in 1/299792458 of a second. A second is determined by the time it takes for a cesium atom to oscillate 9,192,631,770 times.

Interestingly, before the new updated definition, a kilogram is defined by a … kilogram. It’s a kilogram weight called the International Prototype of the Kilogram (IPK), made in 1889 from 90 percent platinum and 10 percent iridium, and kept in a special vault in the BIPM headquarters.

One of the IPK copies in its double bell jars. Photo: NIST

This physical definition of an abstract concept is something that metrologists argue to be continually changing and fails to become accurate as time goes by. The kilogram is the only the SI unit that remains to be defined by a physical object.

Replicas of the kilogram prototypes are used in different parts of the world to serve as national standards. Now and then, these replicas are sent to France to be compared against the actual kilogram prototype.

As expected, these replicas yielded considerable inaccuracies and variance from the SI kilogram prototype. It has been observed to be drifting away from that of the IPK locked away in the vault. It’s unclear whether the copies were losing mass or the IPK was gaining mass, but neither scenario is ideal for scientific precision, even if we’re dealing with mere micrograms.

The new definition of a kilogram is now based on Planck Constant, the ratio of energy to frequency of a photon, measured to its most precise value yet only last year.

“It is only now that we can define the kilogram in terms of a constant of physics – the Planck constant, the speed of light and the resonant frequency of the cesium atom,” Quinn explained.

“Why all three? This is because the units of the Planck constant are kgm2s-1, so we need first to have defined the meter (in terms of the speed of light) and the second (in terms of the cesium atom in the atomic clock).”

So under the new definition, the magnitude of a kilogram would be “set by fixing the numerical value of the Planck constant to be equal to exactly 6.626 069… × 10–34 when it is expressed in the SI unit s–1 m2 kg, which is equal to J s.”

While the changes would not make any perceivable difference if someone buys a kilo of meat from the supermarket, the difference is an essential factor for scientists to consider in their studies moving forward. Because, as noted, base unit standards can rely on other base units. The candela, the ampere, and the mole will be redefined to greater accuracy based on the kilogram. And, as for scientists,

“[The new definition] will considerably improve the understanding and elegance of teaching about units,” Quinn said. “It will open up the way to unlimited improvements in the accuracy of measurements; it will improve the accuracy greatly and extend the possibilities of making accurate measurements at very small and very large quantities.”

Quinn also noted that, while it may look complicated, the new system can be easily understood by anyone. He built a simple balance out of Lego in his basement that can measure directly against the Planck constant, within 5 percent.

A consumer tech and cybersecurity journalist who does content marketing while daydreaming about having unlimited coffee for life and getting a pet llama. I also own a cybersecurity blog called Zero Day.

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Space

Hawaii space observatories reopen after weeks of shutting down

TMT would be a spectacular instrument for space observation but continues to face protests against its construction

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Photo by Daniel Gregoire on Unsplash
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Astronomers at the Mauna Kea observatories can finally return to work after a grueling 4-week pause due to ongoing protests against the construction of a mega observatory called the Thirty Meter Telescope (TMT).

Mauna Kea, the tallest mountain in the world from base to peak, offers clear views of the night sky because of its dark skies from lack of light pollution, good astronomical seeing, low humidity, high elevation of 4,205 meters (13,796 ft), position above most of the water vapor in the atmosphere, clean air, good weather and low latitude location. All of these characteristics place the mountain top as a nearly ideal location to observe the universe by national and international scientists alike.

Although the 13,800-foot summit is already considered home for thirteen different observatories, Hawaiian locals and elders have been adamant to the construction of TMT, arguing that the land is sacred and putting a colossal of infrastructure over the land tarnishes it.

Over the past four weeks, protesters by the thousands have been flocking and creating a human barricade that literally blocked the access ways to the other observatories on top, forcing astronomers to take a mandatory leave from their work.

Astronomers around the world compete for valuable time on the telescopes, and since the observatories closed, the scientists have canceled over 2,000 hours of observational time, according to an outlet. Additionally, this has been considered as the longest shutdown since the location’s five-decade history.

“It was very far-reaching,” says Sarah Bosman of University College London, who lost 3 nights of time to observe distant galaxies with the twin W. M. Keck Observatory telescopes. “Every area of astronomy was affected by this.”

Fortunately, state authorities brokered the deal with the protesters to allow current astronomers access to the observatories and said that construction of a temporary roadway will be built across hardened lava around the protesters’ camp on the summit access road.

Additionally, law enforcement will give protesters an advanced list of all vehicles going up and down to show that they are not associated with TMT.

Apparently, protesters began to gather on the main road leading up to the observatories on July 15, the week in which construction on the site for TMT was supposed to begin.

Significantly, the protesters who gathered at the base of Mauna Kea on Hawaii’s Big Island include indigenous Hawaiian elders, or “kupuna” and has swelled dramatically as the controversy sparked support from the online community.

Despite polls suggesting that Hawaiian were in favor of the construction of TMT, the online community has attracted support from significant figures such as actors Dwayne Johnson and Jason Momoa—who both visited the protest site—and Democratic presidential hopeful Elizabeth Warren. 

TMT is touted to be a $1.4 billion project that aims to provide one of the biggest lenses in the world attached to an observatory, in order to provide better tools to help astronomers study the universe.

Scientists have been sketching the plans for such an instrument as far back as the 1990s, and a global consortium of scientists led by the U.S. and Canada completed the TMT design in 2009. The TMT project would also be the largest telescope in the Northern Hemisphere.

The telescope would be built with support from Canada, China, India, and Japan; a consortium of U.S. universities and international organizations, which will own and operate TMT like many of the observatories operating on Mauna Kea.

However, every step towards the construction of the observatory was met with legal battles ensued by protesters ever since its groundbreaking ceremony in 2014. After nearly a decade of the legal debacle, Hawaii’s Supreme Court ruled in favor of the construction in August 2018, which prompted protesters to take a more active stand against it.

Manua Kea itself has been a flashpoint for controversy ever since the University of Hawaii opened the first telescope there in 1970. Opponents of TMT continue to push the sacred value of the land and also pointed out the mismanagement of the University of Hawaii on the mountaintop observatories. Protesters have also involved other issues with the construction such as Hawaiian nationalism, self-determination, and land rights.

“TMT should build their observatory in their own ancestral lands, not in mine,” says Lilikalā Kameʻeleihiwa, a senior professor at the University of Hawaii’s Hawaiʻinuiākea School of Hawaiian Knowledge. “Imagine if TMT were to put its five-acre monstrosity on top of Notre Dame or the Vatican. How would the French or Italians feel? Would they not protest?”

However, astronomers urge that TMT would be a valuable instrument for human society. It would be able to help astronomers to discover more with what the universe has in store.

“In our lifetime, we could discover life — evidence of life — off the Earth, which would be one of the biggest things [that have] ever happened in science,” says Michael Bolte, an astronomer at the University of California, Santa Cruz, and a member of the TMT board.

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Space

Asteroid nearly hit Earth, and we barely noticed

It’s as big as the one that wiped out dinosaurs.

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Asteroid nearly hit Earth
Source: Pixabay
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A potentially disastrous asteroid merely brushed past Earth, according to a former presidential consultant — noting that the asteroid was massive enough and was similar to the one that wiped out the dinosaurs.

The warning was delivered by Douglas McKinnon who served in the White House under Presidents Ronald Reagan and George H.W. Bush. In July, an asteroid 2019 OK, nicknamed “city killer,” was shot within 40,000 miles away from Earth.

Writing in The Hill, McKinnon said: “Thanks to the collective failure of our world leaders, our only defense today against such an event is dumb luck. On this issue, every leader around the world is in gross dereliction of duty to the people they purport to lead.”

Furthermore, McKinnon urged that world leaders should stop turning a blind eye from the potentially deadly risks and not only put their focus and energy with what’s here on the Earth’s surface but also what lies from the beyond.

Scientists failed to detect 2019 OK until it was close to Earth noting that the sun obscured the asteroid. According to McKinnon, NASA has a record of missing asteroids less than 500 feet long.

He claims one of these could “wipe out a city, a region or a small country and kill millions in the process.”

The former Presidential advisor commented: “So far, only the fickle whims of the universe have prevented the unimaginable. But soon our luck could run out, and Earth will be shaken to its core. President Trump and all world leaders should immediately focus on solutions.”

However, scientist Neil deGrasse Tyson says large space rocks, like the 1990 MU, which measures almost 5 miles in diameter, should not phase us. Instead, the American astrophysicist has insisted the public should be more concerned about smaller asteroids that have the potential to sneak under the radar unnoticed.

Appearing on a Joe Rogan podcast last year, Dr. Tyson explained how it is easy to defend Earth against threats we can easily see.

He said: “It’s all about how much timing we have, what you want to do is go out and nudge it. You just have to give it a sideways velocity relative to its path towards Earth. If you do that, the sideways velocity sort of accumulates and the angle grows.”

In other words, Tyson says that to avoid getting hit by an asteroid hurtling towards Earth, all we need to do is go out into space and plan a method that would knock it off its course; big enough that when it nears our planet, it would completely miss.

“If you do that early enough it will miss Earth, but it’s still out there to harm you on another day,” he said. Additionally, we would at least be able to create such a device in 10 years or so.

However, the Harvard University graduate offered more dim prospects for smaller asteroids, arguing that the good thing about asteroids — big enough to wipe out entire species — is that they are large and visible. In consequence, NASA or any other space agency will only detect the relatively smaller, yet city-killing ones too late and would smash right into our planet.

Notably, most of the Earth’s surface is comprised of water, so most probably, it would hit the ocean instead of directly hitting cities. However, that does not technically mean that the human species would completely be out of harm’s way.

Tyson warned in 2008 that in the event where an asteroid crashes into the Pacific Ocean, it would create a hole with a depth of three miles, at which point it explodes, creating an even wider hole in the Pacific in a hole that’s approximately three miles wide.

“Oceans don’t like having holes in them, so this three-mile-high wall does what? It collapses. It falls back into the hole sloshing against itself with such ferocity that it rises high into the atmosphere and falls back down to the ocean, caveating it again,” he said, adding that “this cycle takes about 50 seconds, you can calculate it.”

That result will be a massive tsunami wave outwards from that location that is 50 feet high. “It’s April 12, 2029, and if it threads the keyhole it will hit Earth on April 13, 2036,” Tyson said.

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Space

Rocket Lab postponed Electron launch

Launch re-scheduled on Monday, August 19, 2019.

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Source: Rocket Lab
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Rocket Lab, a commercial space company, postponed the launch of one of its Electron rockets due to unfavorable weather conditions but is set to place another launch within the next few days. 

According to the Huntington Beach, California-based company, the launch of an Electron rocket was postponed due to high winds at their New Zealand launch site on Friday, August 16.

Rocket Lab initially hoped to launch the Electron’s mission, called “Look Ma, No Hands” from the Māhia Peninsula during a 100-minute window that opened at 8:57 a.m. EDT if ground winds were not too strong. 

“We are standing down from today’s launch attempt due to weather. Surface level winds are 30% over limit,” Rocket Lab representatives wrote in a Twitter update. “We have plenty of back up opportunities in the coming days though. A new target launch day/time will be advised soon.”

If the launch took place and with mother nature’s forgiving weather, Rocket Lab’s Electron rocket would have carried four small satellite launch segments called CubeSats.

Rocket Lab, which was founded back in 2006, offers commercial flights into space via payload delivery such as satellite launches for private companies, which Rocket Lab markets at $5 million per flight. Its Electron rocket has already delivered satellites into space for paying clients. Electron’s latest payload includes CubeSat satellite deliveries for UnseenLabs, Blacksky Global-4, and the US Air Force Space Command. 

French company UnseenLabs asked Rocket Lab to install an ocean-monitoring CubeSat, which aims to build a network of “maritime surveillance” satellites for their customers.

Meanwhile, another Earth-imaging satellite was upon the request of Seattle-based BlackSky Global-4, which aims to add a CubeSat to their growing satellite network.

The final two CubeSats are prototypes built for the U.S. Air Force Space Command to test new technologies in orbit. 

They will serve as an “on-orbit testbed for emerging technologies in 2019,” Air Force officials said in a statement.  The launch of the BlackSky satellite and Air Force CubeSats were arranged by the space rideshare company Spaceflight.

“The demonstration will test new technologies including propulsion, power, communications and drag capabilities for potential applications on future spacecraft,” Air Force officials said. The two satellites were built by Tiger Innovations Inc. in Herndon, Virginia and should last about a year in orbit.

Now, Rocket Lab is targeting another launch date on Monday (August 19) at 8:12 a.m. EDT (1212 GMT). The company has a 14-day window to launch the mission.

If the August 19 launch becomes successful, it will mark the eighth flight of a Rocket Lab Electron in total. 

Specifically, Electron is a two-stage orbital expendable launch vehicle, with an optional third stage that is developed to cover the commercial CubeSats satellites. Its Rutherford engines, manufactured in California, are the first electric-pump-fed engine to power an orbital rocket.

An electric-pump-fed engine is a bipropellant rocket engine in which the fuel pumps are electrically powered, and so all of the input propellants is directly burned in the main combustion chamber, and none is diverted to drive the pumps. This differs from traditional rocket engine designs, in which the pumps are driven by a portion of the input propellants.

Furthermore, the booster is a 57-foot tall (15 meters) spacecraft that is designed to launch small satellites into low-Earth orbit. The rocket can carry payloads of up 500 lbs. (227 kilograms), and can haul multiple CubeSats at a time. 

Rocket Lab first deployed its rocket in May of 2017, which reached space but was not able to reach orbit due to a glitch in the communication equipment on the ground. On its second orbit-reaching flight on January 2018, the company was also able to deploy three of its first CubeSats in space.

The company, later on, launched commercial flights for other companies and institutions in November 2018.

Unlike SpaceX, another commercial space flight provider, Rocket Lab doesn’t currently recover and reuse its rockets. However, the company wants to change this and be able to reuse rockets for more efficient and affordable options.

The company recently announced a reusability roadmap for its Electron launch vehicles, which includes a mid-air recovery effort that will see a helicopter snag the first stage of the Electron rocket as a mid-air retrieval method, saving it from damage and allowing engineers to refurbish it for future launches.

You can watch the launch directly from Rocket Lab’s live stream website. The webcast will begin about 15 minutes before launch time. 

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