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A long and winding road – Skywatching – Castanet.net

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Life here on Earth depends on our supply of heat and light from the sun. A question with a suprising answer is how long does the energy produced in the core of the sun take to reach us?

Let’s see. The sun is about 150 million kilometres away, and light and heat travel at almost 300,000 kilometres a second. So it would take about 8.3 minutes. That is indeed how long that light and heat takes to reach us from the surface of the sun, but to get to us from the sun’s core, we need to add almost a million years to that answer!
 
The sun has a diameter of about 1.5 million kilometres. The energy is produced in the core, which has a diameter of around 300,000 kilometres. In that part of the sun, the temperature is around 15 million degrees Celsius and the pressure about 250 billion times the pressure at the Earth’s surface. Under these conditions atoms come apart and rearrange themselves. The most abundant element in the sun is hydrogen, and under these extreme pressures and temperatures, four hydrogen atoms combine to form an atom of helium, releasing a lot of energy. This nuclear fusion reaction is by far the source of the sun’s energy output. Around four million tonnes of the hydrogen is annihilated and turned into energy every second. The rest is turned into helium. The energy is released in the form of photons, pulses of electromagnetic waves. Gamma rays, X-rays, ultraviolet, visible light, infrared and radio waves are all forms of electromagnetic waves, and come in the form of streams of photons.

In high densities in the sun’s core, almost immediately after an energy photon is produced, it collides with a particle and gets absorbed. Then it gets reradiated in some random direction. This process of absorption and reradiation goes on over and over again. Try this thought experiment. You are in the middle of a field and you want to leave the area. However, after each step or two you pick a new, totally random direction, take a couple more steps, pick a new random direction and so on. How long do you think it would take for you to get off that field? This sort of moving around is known as a “random walk.” This is what those photons in the sun are doing. The part where those photons are random walking around is known as the radiative zone. As the lucky photons work their way outwards, the density drops, so they get to move further before being bounced into some new direction. Eventually, after bouncing around for around a million years on average, they find themselves around 70% of the way to the solar surface. This is an important place because at that level the density has fallen to the point where collisions become unimportant, and another transport process takes over, convection.

Here on Earth, we know that hot air rises. This is because it is warmer than its surroundings and less dense, so it floats upwards. As it rises, it cools. However, as long as it is warmer than its surroundings it will continue to rise. This condition exists in the outer 30% of the sun; from this point the energy is carried upwards as flows of hot, rising gas. This arrives at the surface, the photosphere, a layer a few hundred kilometres thick, which we generally think of as the solar “surface.” Here that gas radiates its energy into space, cools, and sinks down again, to the base of the convection zone, where it heats, rises, and repeats the process. The result is a pattern of rising and forming currents, forming convection cells, just like what we see in a pan of heating oil when about to make some french fries. Once radiated into space, those important energy photons are on the last leg of their trip to us: 150 million kilometres in 8.3 minutes.

  • Venus is hard to see, low in the sunset glow.
  • Look for Mars low in the southeast before dawn, and, to its right, Jupiter and Saturn, close together.
  • The moon will reach first quarter on the 29th.

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What the future of the space station looks like after SpaceX’s historic launch – The Verge

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With the success of SpaceX’s Crew Dragon launch this weekend, NASA now has the capability to launch its own astronauts from the US once again — and that means changes are in store for the future of the International Space Station. Soon, a new suite of vehicles could be regularly flying people to the station from the Florida coast, along with the Russian Soyuz rocket that has been solely responsible for taking humans to the outpost since 2011.

This will be a new era of human spaceflight where private vehicles and state-operated vehicles fly along aside one another, getting humans into space, and to the ISS. Here’s how traffic to the space station will evolve as SpaceX and NASA’s other commercial partner, Boeing, start sending people to and from the ISS on a regular basis.

The Russian relationship

Since the end of the Space Shuttle program in 2011, NASA and Russia’s space corporation, Roscosmos, have been locked in a symbiotic relationship. NASA needed Russia in order to get its own astronauts and international partners to the International Space Station. Russia benefitted from NASA’s money — one seat on Russia’s Soyuz capsule runs NASA upward of $80 million.

That’s been good for the relationship between NASA and Roscosmos. “Mutual dependency actually makes for a pretty good working relationship,” Todd Harrison, the director of the Aerospace Security Project at the Center for Strategic and International Studies (CSIS), tells The Verge. “By all accounts, everyone I’ve talked to at NASA has said that even as the geopolitical relationship between the United States and Russia has deteriorated, their relationship — when it comes to the ISS — has remained as strong as ever.”

Now that NASA has a brand-new ride, that once codependent relationship between the space agencies is going to evolve. NASA administrator Jim Bridenstine said that he has had discussions with Dmitry Rogozin, director general of Roscosmos, about trading seats on each nation’s vehicles moving forward, rather than purchasing them. “If we are going to maintain a complement of both Russian and American astronauts on board, then we need to be willing to launch Russian cosmonauts on Commercial Crew, and they need to be willing to launch American astronauts on the Soyuz,” Bridenstine said. “And my last conversations with Dmitry Rogozin, I think we were both in strong agreement that was necessary for both nations as we move forward.”

Rogozin publicly congratulated NASA and SpaceX on the launch. That positive reaction stands in stark contrast to Rogozin’s comments from 2014, when he publicly decried US sanctions against the Russian space industry and made a dig at NASA’s Commercial Crew Program. “After analyzing the sanctions against our space industry, I suggest to the USA to bring their astronauts to the International Space Station using a trampoline,” Rogozin tweeted at the time. (SpaceX CEO Elon Musk joked about this comment after the launch this weekend, arguing that “the trampoline is working.”)

The reality is NASA’s dependency on Russia’s Soyuz rocket gave Roscosmos an important reason to keep its rockets and capsules in production. It brought in a lot of funding, too. “What’s going to change is that Russia is losing a major source of revenue for their space industry,” says Harrison. “As the US will no longer need to buy Soyuz flights.” This year, the budget for Roscosmos is about 176 billion rubles, according to a report in TASS, which equates to $2.77 billion. It’s a fraction of NASA’s budget, which is set at $22.6 billion for 2020. All told, NASA’s purchasing of Soyuz seats accounted for 17 percent of the annual Roscosmos budget in 2018, according to CSIS.

As a result of this new operational shift, it’s possible we could see fewer flights of the Soyuz in the future, Harrison says. “Economically, demographically, they are in a decline,” he says. “And there’s little chance they’re going to pull out anytime soon. So in terms of a space power, they’ve got the technology, but they are going to be able to do less and less with that technology as years go by.”

For now, NASA maintains that its relationship with Roscosmos is strong, and the space agency did purchase one additional seat on a Russian Soyuz rocket for this fall. But after that, the new trading will begin, and it’ll become more clear how that affects the bottom line for Roscosmos.

Open for business

Though SpaceX was the first to fly astronauts, the company is not the only company working on a private spacecraft for NASA. Boeing is still developing its own crew capsule, the CST-100 Starliner, aimed at doing the same thing as SpaceX’s Crew Dragon. But there’s still a way to go before people will be flying on the vehicle.

Boeing conducted an uncrewed test flight of the Starliner in December, which didn’t go to plan. A number of software glitches surfaced during the mission, ultimately preventing the capsule from reaching the space station as expected. The company had to bring the Starliner home early without ever demonstrating its docking capabilities. Boeing will have to redo that flight, without crew on board, sometime this fall.

That means for the year ahead, SpaceX will probably be the only private company sending astronauts to the ISS. But once Boeing demonstrates it can dock the Starliner safely with the space station and then bring the capsule home, the company will also send its own crew into orbit. When that happens, three vehicles capable of carrying NASA astronauts to the station will be in operation, when there was just one before.

With this change, eventually other people might join NASA astronauts on journeys to the space station. Bridenstine has made the main goal of the Commercial Crew Program very clear: return human spaceflight to American soil. But a second goal of the program has been to open up access to space, allowing both SpaceX and Boeing to sell seats on their vehicles to private customers. NASA is also making the space station available for commercial opportunities, something the agency has been strictly against in the past.

SpaceX has already announced plans to send tourists into space on the Crew Dragon. The company is sending four tourists on a trip to orbit. They also plan to send private citizens to the ISS next year for a private company called Axiom, which plans to build its own space station to launch in 2024. And there’s a big possibility that Tom Cruise will fly on the Crew Dragon to film some kind of movie on the ISS in the future.

Whether these kinds of private trips become routine depends on the price. One seat on SpaceX’s Crew Dragon runs NASA about $55 million, while one seat on Boeing’s Starliner runs $90 million. While SpaceX is less expensive, for the average customer, both costs are still well out of reach. “A lot of it depends on how much they can get the cost down for both SpaceX and Boeing,” Harrison says. “SpaceX clearly has its eye on space tourism, in offering flights to folks that can afford it, and that would generate more volume for sure.”

Harrison argues this could go a long way toward commercializing the ISS — using the station for private production, manufacturing, or space tourism. It’s something that NASA is very keen to make happen. Once SpaceX and Boeing start flying regularly, we’ll find out whether other non-space companies are even interested in sending people and property to the space station. It’s possible they may not be. “It’s not clear that the business case will close on these things,” says Harrison. “We’ve got to see experimentation, adaptation, before we really know what’s going to work in terms of commercialization, and what’s not going to work.”

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Astronomers Confirm Earth-Like Planet Orbiting Nearest Star – ExtremeTech

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Scientists used to wonder if planets were common throughout the universe, and now we know: they are. Observations with ground-based and space telescopes like Kepler and TESS have proven planets are extremely common. There’s even a small, Earth-like planet right next door orbiting Proxima Centauri. We can say that with confidence now that a team from the University of Geneva has confirmed and refined the initial observations. While Proxima Centauri b is similar in size to Earth, it might not be a great place to vacation. 

Scientists discovered Proxima b in 2016, but it took longer to confirm because of how it was detected. Most exoplanet identifications over the past decade come from the Kepler Space Telescope, which used the transit method of detection. When an exoplanet orbits its star, it can block out the star’s light for brief periods. By tracking these dips in brightness, we can infer the properties of the planet. This is a reliable way to spot planets, but it only works when the plane of the other solar system is aligned with ours. That is not the case for Proxima Centauri, the closest star to Earth at just 4.2 light-years distant. 

A team from the European Southern Observatory discovered Proxima b with the aid of HARPS (High Accuracy Radial Velocity Planet Searcher), a sophisticated spectrograph at the La Silla Observatory in Chile. A spectrograph can measure the small wobbles in a star’s motion that can indicate the presence of an exoplanet. Now, the University of Geneva team has fired up ESPRESSO, a more powerful spectrograph in the same observatory to confirm Proxima b. 

Artist's impression of the planet orbiting Proxima Centauri

This is what we think it looks like on the surface of Proxima b, a temperate exoplanet orbiting in the habitable zone around a red dwarf in our nearest neighboring star system, Alpha Centauri. Image: ESO

The ESPRESSO data confirms Proxima b is there and that it’s just 1.17 times Earth mass. It also completes a full solar orbit in 11.2 Earth days. Despite being so close to the star, Proxima b is inside the habitable zone because Proxima Centauri is a small, cool red dwarf. With its presence confirmed, the team can also say with certainty that Proxima b gets about 400 times more X-ray radiation than Earth. 

Because Proxima b doesn’t transit the star, it’s harder to gather data about its composition. We know it’s only slightly more massive than Earth, so it’s probably a rocky world. However, no one knows if it might have an atmosphere that could protect it from all that radiation. There’s a lot more to learn about Proxima b, but we might need to wait for future instruments like the James Webb Space Telescope to help us get there.

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NGen Funding Continues to Support Canada's COVID-19 Response – Stockhouse

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GUELPH, Ontario, and Mississauga, Ontario, June 02, 2020 (GLOBE NEWSWIRE) — Next Generation Manufacturing Canada (NGen), the industry-led organization behind Canada’s Advanced Manufacturing Supercluster, has announced funding for Precision Biomonitoring to support the company’s production of test kits to identify COVID-19.

Precision Biomonitoring has received almost $5 million in funding to work directly with Canadian manufacturers to increase production of its TripleLock™ SARS-CoV-2 Go-Strips, a rapid response test that will allow for the early identification of COVID-19.

Rapid, accurate and available testing for COVID-19 is critical to the measures being undertaken by health authorities in Canada as they work to control the spread of the virus and move towards reopening the economy, ensuring the safety of Canadians as they head back into the workplace. Testing capacity has been an ongoing issue as global demand for test kits coupled with limited domestic supply has created shortages.

“Widespread testing is going to be an important part of our vigilance as Canada continues to flatten the curve. I am happy to see the superclusters stepping up in a big way to leverage their membership and Canada’s strong industrial base as part of this effort. The rapid manufacturing of these point-of-care test kits will help ensure that more Canadians can be tested for COVID-19 in a timely manner,” said the Honourable Navdeep Bains, Minister of Innovation, Science and Industry.

“Collaboration among Canada’s advanced manufacturing companies has allowed for a rapid response to the COVID-19 pandemic, creating innovative solutions and mobilizing advanced technologies to address the demand for test kits,” said Jayson Myers, CEO at NGen. “The flexibility and adaptability that advanced manufacturing allows has been critically important in addressing the challenges presented by COVID-19, and will continue to be so as governments move to re-open the Canadian economy.”

Leveraging the capabilities of Canadian manufacturers and partners such as Evik Diagnostics, the Canadian Food Inspection Agency, Shared Value Solutions, McMaster Health Science Centre, Sunnybrook Health Science Centre and the Canadian National Microbiology Lab, Precision Biomonitoring anticipates a production rate capacity of 10,000 units per day or greater.

“Advancing Canadian manufacturing enables us to leverage local capabilities to mitigate manufacturing challenges,” says John Laughlin, CTO at NGen. “We are proud to help drive these collaborative relationships that will position Canada as a world leader in manufacturing point-of-need DNA surveillance and detection tools and ensure that all Canadians, including indigenous peoples, will have adequate access to COVID-19 testing.”

“Developing Canadian manufacturing is not only promising for our response efforts for COVID-19, but also provides a strong foundation as we look to expand into the growing mobile DNA applications market,” says Mario Thomas, CEO, Precision Biomonitoring.

The funding for the project comes from NGen’s commitment to invest $50 million to support companies as they rapidly respond to the COVID-19 pandemic by building a Canadian supply of critically needed technologies, equipment, and medical devices.

About NGen – Next Generation Manufacturing Canada

NGen is the industry-led community behind Canada’s most transformative advanced manufacturing projects. NGen members come from every part of the country and cut across Canada’s manufacturing, technology, advanced research, and start-ups sectors. NGen is an objective facilitator of connections and collaboration among its members, identifying opportunities, building capabilities, and supporting advanced manufacturing decisions. NGen’s industry collaborations bring together talent, opportunity, funding, and business know-how to reduce risk and help business leaders make better choices. NGen is Canada’s Supercluster for Advanced Manufacturing, securing funding from public and private sources, including $230 million in matching dollars from the federal government’s Innovation Superclusters Initiative, to support greater private sector investment in advanced manufacturing projects. NGen seeks to add $13.5 billion dollars and 13,500 new jobs to the economy over the next 10 years by growing world-leading advanced manufacturing capabilities in Canada.

About Precision Biomonitoring

Founded in 2016 by a team of scientists from the University of Guelph’s Biodiversity Institute of Ontario, Precision Biomonitoring provides TripleLock™ onsite eDNA surveillance platform solutions that give customers earlier detection of organisms for a more rapid response. Customers are any organizations that need onsite surveillance and rapid identification of any organism in any environment. The Precision Biomonitoring team is at the forefront of technological innovations in the genomics industry. Our vision is a world where we can identify any organism on the spot, in an instant, anywhere on the planet.

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