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New Observations Agree That the Universe is 13.77 Billion Years old – Universe Today

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The oldest light in the universe is that of the cosmic microwave background (CMB). This light was formed when the dense matter at the beginning of the universe finally cooled enough to become transparent. It has traveled for billions of years to reach us, stretched from a bright orange glow to cool, invisible microwaves. Naturally, it is an excellent source for understanding the history and expansion of the cosmos.

The CMB is one of the ways we can measure the rate of cosmic expansion. In the early universe, there were small fluctuations of density and temperature within the hot dense sea of the big bang. As the universe expanded, the fluctuations expanded as well. So the scale of fluctuations we see in the cosmic microwave background today tells us how must the universe has grown. On average, the fluctuations are about a billion light-years across, and this gives us a value for the rate (the Hubble parameter) as somewhere between 67.2 and 68.1 km/sec/Mpc.

The Atacama Cosmology Telescope. Credit: Jon Ward

Of course, the CMB isn’t the only way you can measure the Hubble parameter. In an earlier post, I talked about how you can use variable stars and distant supernovae to create a cosmic distance ladder that tells you the rate of expansion. The problem is, this alternative method gives a larger value for the Hubble parameter. If the supernova method is right, then the universe is younger and has expanded more quickly than the CMB scale seems to support. For a while, the hope has been that new observations and new methods of measuring cosmic expansion would solve this problem, but a new study dashes those hopes. This study looked at the cosmic microwave background using the Atacama Cosmology Telescope (ACT) in Northern Chile.

How the CMB arises from last scattering. Credit: Yacine Ali-Haïmoud

Most detailed observations of the CMB are made with satellites such as the Planck satellite. Being in space gives you a clear view of the cosmic remnant heat, letting you measure temperature fluctuations. The Atacama Cosmology Telescope is land-based, but it’s high in the Andes, where the air is very thin and dry, so it gets a reasonably good view of the CMB. But it is also specially designed to look at the polarization of the cosmic light.

The early universe was filled with light, but because it was so hot and ionized, photons couldn’t travel far before scattering off a proton or electron. But around 380,000 years after the big bang, matter in the early universe cooled enough to become neutral hydrogen and helium, which is largely transparent to light. The CMB light we see made one last scattering before things cleared enough for it to reach us. When light scatters off something, it is oriented, or polarized, relative to that scatter. Thus all the CMB light is polarized, and its orientation tells us about the early universe.

The team used this polarization to determine the age and expansion rate of the cosmos. Just as the size of uniform temperature regions in the CMB tells us the rate of cosmic expansion, so does the size of uniform polarization regions. The team measured the polarization scale more precisely than ever before and determined the Hubble parameter is between 66.4 and 69.4 km/sec/Mpc. This gives the age of the universe as 13.77 billion years, which is consistent with Planck’s measurements of the CMB.

So now we have two independent precision measures of cosmic expansion from the CMB, and they agree. But other measurements using supernovae disagree, so there’s clearly something we don’t understand here. At this point what is clear is that some aspect of our cosmological model needs to be revised.

Reference: Choi, Steve K., et al. “The Atacama Cosmology Telescope: a measurement of the cosmic microwave background power spectra at 98 and 150 GHz.” Journal of Cosmology and Astroparticle Physics 2020.12 (2020): 045.

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NASA declares Mars digger dead after two years – Mashable

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Image: IPGP/Nicolas Sarter/nasa

NASA announced on Thursday that a “mole” on Mars has ended its mission after landing on the Red Planet nearly two years ago.

The mole — also called a digger, drill, and probe — was built by the German Aerospace Center (DLR) and deployed by NASA’s InSight lander. Its purpose was to drill 16 feet into Martian soil to take its temperature and…well, it never managed to do that. 

The digger had drilled down merely 14 inches before getting stuck in the first month of its mission. Months later in Oct. 2019, NASA engineers made a plan to put the digger back on track by using a robotic scoop to help refill the 14 inches and support the digger in its next attempt at burrowing down 16 feet. The team at NASA was confident that the probe was finally ready to go, but they were wrong.

NASA’s next idea, in Feb. 2020, was to direct the InSight lander to push on the probe with its robotic arm.

That didn’t work, either. After attempting to use the scoop on InSight’s robotic arm once again on Jan. 9, 2021, the probe made 500 additional hammer strokes with no progress. At that point, the team declared the probe dead. 

“We’ve given it everything we’ve got, but Mars and our heroic mole remain incompatible,” said DLR’s Tilman Spohn in NASA’s announcement. 

There is good news, however. Spohn said that the work on this probe will benefit future missions, as they’ve learned a lot about the surface of Mars. 

Thomas Zurbuchen, associate administrator for science at NASA’s Washington headquarters, said he was proud of the mission’s team — and that their work was purposeful. “This is why we take risks at NASA — we have to push the limits of technology to learn what works and what doesn’t,” he said.

“In that sense, we’ve been successful: We’ve learned a lot that will benefit future missions to Mars and elsewhere,” Zurbuchen continued, “and we thank our German partners from DLR for providing this instrument and for their collaboration.”

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NASA cuts short ground test of its giant moon rocket – Al Jazeera English

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The test is a vital step in NASA’s Artemis programme to put the first woman and the next man on the Moon in 2024.

NASA ignited all four engines of a deep space exploration rocket – the Space Launch System (SLS) – for the first time on Saturday, but the “hot fire” test ended much earlier than expected.

Mounted in a test facility at NASA’s Stennis Space Center in Mississippi, the SLS’s 212-foot (65-metre) tall core stage roared to life at 4:27pm local time (22:27 GMT) for just more than a minute – well short of the roughly four minutes engineers needed to stay on track for the mega rocket’s first launch in November this year.

During the live broadcast of the test, NASA did not explain the reason for the early shutdown, but Wayne Hale, a former manager of NASA’s space shuttle programme, suggested a “major component failure”.

The fiery show, the last leg of NASA’s nearly year-long “Green Run” test campaign, was a vital step for the space agency and its top SLS contractor, Boeing, before the rocket’s debut launch in November.

The success of that unmanned mission, called “Artemis 1”, will set the stage for the first landing on the Moon by humans since the Apollo 17 mission in 1972. US President Donald Trump has pushed for that trip – which will also see the first woman on the Moon – to happen by 2024.

It was unclear whether Boeing and NASA would have to repeat Saturday’s test, a prospect that could push the debut launch into 2022.

NASA administrator Jim Bridenstine, speaking at a news conference after the test, said the agency “got lots of data that we’re going to be able to sort through” to determine if a do-over is needed.

NASA’s SLS program manager John Honeycutt cautioned the data review from the test is continuing and told reporters the turnaround time for another hot fire test could be roughly one month.

The expendable super heavy-lift SLS is three years behind schedule and nearly $3bn over budget.

Critics have long argued for NASA to retire the rocket’s shuttle-era core technologies, which have launch costs of $1bn or more per mission, in favour of newer commercial alternatives that promise lower costs.

By comparison, it costs as little as $90m to fly the massive, but less powerful, Falcon Heavy rocket designed and manufactured by Elon Musk’s SpaceX, and some $350m per launch for United Launch Alliance’s legacy Delta IV Heavy.

While newer, more reusable rockets from both companies – SpaceX’s Starship and United Launch Alliance’s Vulcan – promise heavier lift capacity than the Falcon Heavy or Delta IV Heavy, potentially at a lower cost, SLS backers have argued it would take two or more launches on those rockets to launch what the SLS could carry in a single mission.

Reuters reported in October that President-elect Joe Biden’s space advisers aimed to delay Trump’s 2024 goal, casting fresh doubts on the long-term fate of SLS just as SpaceX and Jeff Bezos’ Blue Origin scramble to bring rival new heavy-lift capacity to market.

NASA and Boeing engineers have stayed on a 10-month schedule for the Green Run “despite having significant adversity this year,” Boeing’s SLS manager John Shannon told reporters this week, citing five tropical storms and a hurricane that hit Stennis, as well as a three-month closure after some engineers tested positive for the coronavirus in March.

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Watch NASA's historic Moon mission rocket test at 5PM ET – Yahoo Canada Shine On

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Eat This, Not That!

Here’s How to Get Your COVID Vaccine in Your State

The coronavirus vaccine is now available, the “light at the end of the tunnel” of this deadly pandemic. But confusion about who is eligible, how to get yours, and where to go seems to be changing every day. “The vaccine rollout in the United States has been a dismal failure so far,” President-elect Joe Biden said Friday. “The honest truth is this, things will get worse before they get better. And the policy changes we are going to be making, they’re going to take time to show up in the COVID statistics.” In the following story, you’ll find links to every state’s vaccination rollouts, so you can find the latest information. Read on—and to ensure your health and the health of others, don’t miss these Sure Signs You’ve Already Had Coronavirus. 1 Alabama If you live in Alabama, you can find out how to get vaccinated by going to the state’s vaccine website, here. 2 Alaska If you currently live in Alaska, you can find out how to get the vaccine by going to the state’s vaccine website, here. 3 Arizona If you reside in Arizona, you can find out how to get vaccinated by going to the state’s vaccine website, here. 4 Arkansas If you live in Arkansas, you can find out how to get the vaccine by going to the state’s vaccine website, here. 5 California If you reside in California, you can find out how to get vaccinated by going to the state’s vaccine website, here. 6 Colorado If you currently live in Colorado, you can find out how to get vaccinated by going to the state’s vaccine website, here. 7 Connecticut If you live in Connecticut, you can find out how to get the vaccine by going to the state’s vaccine website, here. 8 Delaware If you live in Delaware, you can find out how to get vaccinated by going to the state’s vaccine website, here. 9 Florida If you currently reside in Florida, you can find out how to get vaccinated by going to the state’s vaccine website, here. 10 Georgia If you’re located in Georgia, you can find out how to get the vaccine by going to the state’s vaccine website, here. 11 Hawaii If you live in Hawaii, you can find out how to get vaccinated by going to the state’s vaccine website, here. 12 Idaho If you’re located in Idaho, you can find out how to get the vaccine by going to the state’s vaccine website, here. 13 Illinois If you reside in Illinois, you can find out how to get the vaccine by going to the state’s vaccine website, here. 14 Indiana If you live in Indiana, you can find out how to get vaccinated by going to the state’s vaccine website, here. 15 Iowa If you take up residence Iowa, you can find out how to get vaccinated by going to the state’s vaccine website, here. 16 Kansas If you live in Kansas, you can find out how to get vaccinated by going to the state’s vaccine website, here. 17 Kentucky If you live in Kentucky, you can find out how to get vaccinated by going to the state’s vaccine website, here. 18 Louisiana If you take up residence in Louisiana, you can find out how to get the vaccine by going to the state’s vaccine website, here. 19 Maine If you live in Maine, you can find out how to get the vaccine by going to the state’s vaccine website, here. 20 Maryland If you’re located in Maryland, you can find out how to get vaccinated by going to the state’s vaccine website, here. 21 Massachusetts If you live in Massachusetts, you can find out how to get vaccinated by going to the state’s vaccine website, here. 22 Michigan If you’re located in Michigan, you can find out how to get the vaccine by going to the state’s vaccine website, here. 23 Minnesota If you reside in Minnesota, you can find out how to get the vaccine by going to the state’s vaccine website, here. 24 Mississippi If you live in Mississippi, you can find out how to get vaccinated by going to the state’s vaccine website, here. 25 Missouri If you take up residence in Missouri, you can find out how to get vaccinated by going to the state’s vaccine website, here. 26 Montana If you live in Montana, you can find out how to get the vaccine by going to the state’s vaccine website, here. 27 Nebraska If you reside in Nebraska, you can find out how to get vaccinated by going to the state’s vaccine website, here. 28 Nevada If you live in Nevada, you can find out how to get vaccinated by going to the state’s vaccine website, here. 29 New Hampshire If you live in New Hampshire, you can find out how to get vaccinated by going to the state’s vaccine website, here. 30 New Jersey If you live in New Jersey, you can find out how to get vaccinated by going to the state’s vaccine website, here. RELATED: 7 Tips You Must Follow to Avoid COVID, Say Doctors 31 New Mexico If you reside in New Mexico, you can find out how to get vaccinated by going to the state’s vaccine website, here. 32 New York If you live in New York, you can find out how to get vaccinated by going to the state’s vaccine website, here. 33 North Carolina If you live in North Carolina, you can find out how to get vaccinated by going to the state’s vaccine website, here. 34 North Dakota If you live in North Dakota, you can find out how to get the vaccine by going to the state’s vaccine website, here. 35 Ohio If you live in Ohio, you can find out how to get vaccinated by going to the state’s vaccine website, here. 36 Oklahoma If you live in Oklahoma, you can find out how to get vaccinated by going to the state’s vaccine website, here. 37 Oregon If you’re located in Oregon, you can find out how to get vaccinated by going to the state’s vaccine website, here. 38 Pennsylvania If you live in Pennsylvania, you can find out how to get vaccinated by going to the state’s vaccine website, here. 39 Rhode Island If you’re located in Rhode Island, you can find out how to get the vaccine by going to the state’s vaccine website, here. 40 South Carolina If you live in South Carolina, you can find out how to get vaccinated by going to the state’s vaccine website, here. RELATED: Dr. Fauci Just Said When We’d Be Back to “Normal” 41 South Dakota If you take up residence in South Dakota, you can find out how to get vaccinated by going to the state’s vaccine website, here. 42 Tennessee If you live in Tennessee, you can find out how to get vaccinated by going to the state’s vaccine website, here. 43 Texas If you live in Texas, you can find out how to get vaccinated by going to the state’s vaccine website, here. 44 Utah If you live in Utah, you can find out how to get the vaccine by going to the state’s vaccine website, here. 45 Vermont If you take up residence in Vermont, you can find out how to get vaccinated by going to the state’s vaccine website, here. 46 Virginia If you reside in Virginia, you can find out how to get vaccinated by going to the state’s vaccine website, here. 47 Washington If you live in Washington, you can find out how to get vaccinated by going to the state’s vaccine website, here. 48 West Virginia If you live in West Virginia, you can find out how to get the vaccine by going to the state’s vaccine website, here. 49 Wisconsin If you live in Wisconsin, you can find out how to get vaccinated by going to the state’s vaccine website, here. 50 Wyoming If you live in Wyoming, you can find out how to get vaccinated by going to the state’s vaccine website, here. 51 Washington DC If you currently live in Washington DC, you can find out how to get vaccinated by going to the state’s vaccine website, here. 52 How to Survive This Pandemic As for yourself, follow the public health fundamentals and help end this surge, no matter where you live—wear a face mask, social distance, avoid large crowds, don’t go indoors with people you’re not sheltering with (especially in bars), practice good hand hygiene, get vaccinated when it becomes available to you, and to protect your life and the lives of others, don’t visit any of these 35 Places You’re Most Likely to Catch COVID.

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