Connect with us

Science

How old are we? Debate over the age of the universe just got a bit more complicated – CBC.ca

Published

 on


Another telescope is helping us better understand the age of the universe and its future.

Using the Atacama Cosmology Telescope (ACT) in Chile, a group of astronomers say their observations support an earlier estimate as to the age of the universe: 13.77 billion years, give or take 40 million years. Their paper was released on the pre-print publishing service arXiv.org on Wednesday and submitted to the Journal of Cosmology and Astroparticle Physics.

The estimate supports observations taken by the European Space Agency’s Planck space telescope in the early 2010s. 

Over the years, there have been other studies that have disputed that number. For example, in 2019, a study published in the journal Science suggested the universe was 11.2 billion years old.

A portion of a new picture of the oldest light in the universe taken by the Atacama Cosmology Telescope. This part covers a section of the sky 50 times the moon’s width, representing a region of space 20 billion light-years across. (ACT Collaboration)

“For a half dozen years, I’d say even more … within the past three years, there has been one conference after another all over the world completely focused on this issue where one group comes up and they say, ‘Oh, this is what we get,’ and the other group comes up and says, ‘This is what we get,” said Richard Bond, co-author of the paper and director of the Canadian Institute for Theoretical Astrophysics at the University of Toronto.

“We call it the Hubble tension.”

Why isn’t there a clear-cut answer?

It all comes down to the methods used to calculate the expansion of the universe.

Stars vs. the Big Bang

In 1929, astronomer Edwin Hubble found that the universe is expanding. Ever since, scientists have attempted to calculate just how fast that’s occurring. The rate of expansion is called the Hubble Constant.

But the challenge with determining the age of our universe — which in turn helps us better understand not only its past but also its future — is that there are a few methods used to make the calculations.

One involves looking at things that are relatively nearby, cosmologically speaking, such as supernovas (exploding stars) and a particular type of star that varies in brightness, called a Cepheid variable. 

Yet another involves looking far, far back, to a time shortly after the universe came to be — in particular at the cosmic microwave background radiation, or CMB, left over from the rapid birth of the universe, some 380,000 years following the Big Bang.

ACT also used this method, though from a ground-based telescope. But one advantage it had over Planck was the ability to better measure polarization of the CMB, which tells the scientists in what direction the light is moving. This allows it to be more precise.

New physics?

Just how close were their findings to Planck’s?

The space telescope put the rate of the expansion of the universe at 67.5 kilometres per second per megaparsec (one megaparsec is 3.26 million light years). The new findings put that at 67.6 kilometres per second per megaparsec.

“What ACT has done is taken away the option that the CMB measurements were just a fluke of some kind,” said Mark Halpern, a professor at the University of British Columbia’s department of physics and astronomy in Vancouver and co-author of the paper.

This is an important step, the authors say, in trying to determine whether astrophysicists truly understand the universe.

The Atacama Cosmology Telescope in Chile measures the oldest light in the universe, known as the cosmic microwave background. Using those measurements, scientists can calculate the universe’s age. (Debra Kellner)

“If we want the universe to be consistent, then what we need to understand is: [Is] it that we have [something] we haven’t accounted for in any of the measurements? Or is there some kind of new physics?” said Renee Hlozek, co-author and a professor of astrophysics at the Dunlap Institute at U of T’s department of astronomy and astrophysics.

“Because it could be that we’re living in a universe that looks a certain age close to us, but then either the expansion rate changes over time or there’s exotic physics that means it’s a different age.”

Wendy Freedman is an astronomy professor at the University of Chicago’s department of astronomy and astrophysics who was not involved in the study. She also researches the expansion of the universe and has used a particular type of star — a red giant — as a method of calculating the expansion.

“I think it’s a really superb piece of work,” she said of the new paper. “It’s a major study — and looking through the papers, they have paid a huge amount of attention to details and possible uncertainties and errors and run tests and checked through their data.”

Freedman said while the data supports Planck, there’s still something fundamental that we don’t understand, something that the authors themselves acknowledge. 

But with the new ground-based findings, they hope that this will be another piece in the puzzle in an attempt to understand what’s going on in our universe — in particular how it will ultimately cease to be.

“If we understand the age of the universe now, that can actually help us have a better view of how this is going to end,” Hlozek said.

Let’s block ads! (Why?)



Source link

Continue Reading

Science

China's sample-return Moon mission touches down – BBC News

Published

 on



.css-94m6rd-HeadingWrapperborder-bottom:solid 1px #BABABA;padding-bottom:1.5rem;.css-94m6rd-HeadingWrapper > *:not([hidden]):not(style) ~ *:not([hidden]):not(style)margin-top:1rem;.css-vk3nhx-ComponentWrappermargin:1.5rem 0;

.css-1759m9z-StyledFigurefont-family:ReithSans,Helvetica,Arial,freesans,sans-serif;font-weight:400;font-size:0.875rem;line-height:1.125rem;

.css-kwaqyc-StyledFigureContainerposition:relative;

.css-1xtcmof-Placeholderposition:relative;display:block;padding-bottom:56.25%;background-color:#EEEEEE;.css-1xtcmof-Placeholder imgoverflow:hidden;position:absolute;top:0;right:0;bottom:0;left:0;display:-webkit-box;display:-webkit-flex;display:-ms-flexbox;display:flex;-webkit-box-pack:center;-webkit-justify-content:center;-ms-flex-pack:center;justify-content:center;-webkit-align-items:center;-webkit-box-align:center;-ms-flex-align:center;align-items:center;width:100%;height:100%;object-fit:cover;

.css-evoj7m-Imagedisplay:block;width:100%;height:auto;

.css-1ecljvk-StyledFigureCopyrightposition:absolute;bottom:0;right:0;background:#3F3F42;color:#EEEEEE;padding:0.25rem 0.5rem;text-transform:uppercase;CNSA

.css-1rnnz6t-StyledFigureCaptionbackground:#3F3F42;color:#EEEEEE;padding:1rem;

.css-uf6wea-RichTextComponentWrappermargin:1rem 0;max-width:36.25rem;

.css-83cqas-RichTextContainercolor:#3F3F42;.css-83cqas-RichTextContainer > *:not([hidden]):not(style) ~ *:not([hidden]):not(style)margin-top:1rem;

.css-14iz86j-BoldTextfont-weight:bold;China has successfully put another probe on the Moon.

Its robotic .css-yidnqd-InlineLink:linkcolor:#3F3F42;.css-yidnqd-InlineLink:visitedcolor:#696969;.css-yidnqd-InlineLink:link,.css-yidnqd-InlineLink:visitedfont-weight:bolder;border-bottom:1px solid #BABABA;-webkit-text-decoration:none;text-decoration:none;.css-yidnqd-InlineLink:link:hover,.css-yidnqd-InlineLink:visited:hover,.css-yidnqd-InlineLink:link:focus,.css-yidnqd-InlineLink:visited:focusborder-bottom-color:currentcolor;border-bottom-width:2px;color:#B80000;@supports (text-underline-offset:0.25em).css-yidnqd-InlineLink:link,.css-yidnqd-InlineLink:visitedborder-bottom:none;-webkit-text-decoration:underline #BABABA;text-decoration:underline #BABABA;-webkit-text-decoration-thickness:1px;text-decoration-thickness:1px;-webkit-text-decoration-skip-ink:none;text-decoration-skip-ink:none;text-underline-offset:0.25em;.css-yidnqd-InlineLink:link:hover,.css-yidnqd-InlineLink:visited:hover,.css-yidnqd-InlineLink:link:focus,.css-yidnqd-InlineLink:visited:focus-webkit-text-decoration-color:currentcolor;text-decoration-color:currentcolor;-webkit-text-decoration-thickness:2px;text-decoration-thickness:2px;color:#B80000;Chang’e-5 mission touched down a short while ago with the aim of collecting samples of rock and dust to bring back to Earth.

The venture has targeted Mons Rümker, a high volcanic complex in a nearside region known as Oceanus Procellarum.

The lander is expected to spend the next couple of days examining its surroundings and gathering up surface materials.

It has a number of instruments to facilitate this, including a camera, spectrometer, radar, a scoop and a drill.

The intention is to package about 2kg of “soil”, or regolith, to send up to an orbiting vehicle that can then transport the samples to Earth.

It’s 44 years since this was last achieved. That was the Soviet Luna 24 mission, which picked up just under 200g.

Unlike the launch of the mission a week ago, the landing was not covered live by Chinese TV channels.

Only after the touchdown was confirmed did they break into their programming to relay the news.

Images taken on the descent were quickly released with the final frame showing one of the probe’s legs casting a shadow on to the dusty lunar surface.

.css-1jltxxc-ComponentWrapper-SocialEmbedComponentWrappermargin:1.5rem 0;.css-1jltxxc-ComponentWrapper-SocialEmbedComponentWrapper iframemax-width:100%;.css-1jltxxc-ComponentWrapper-SocialEmbedComponentWrapper div > blockquoteborder:1px solid #BABABA;border-radius:4px;padding:1rem;max-width:36.25rem;margin-bottom:0.5rem;.css-1jltxxc-ComponentWrapper-SocialEmbedComponentWrapper spandisplay:block;font-size:0.875rem;line-height:1.125rem;margin-bottom:0.5rem;.css-1jltxxc-ComponentWrapper-SocialEmbedComponentWrapper .fb-postmax-width:100%;margin-bottom:0.5rem;.css-1jltxxc-ComponentWrapper-SocialEmbedComponentWrapper .fb-post spanmax-width:100%;

The BBC is not responsible for the content of external sites.View original tweet on Twitter

.css-1pzprxn-BulletListContainermargin-left:1.5rem;.css-1pzprxn-BulletListContainer *:not([hidden]):not(style) ~ *:not([hidden]):not(style)margin-top:1rem;.css-1pzprxn-BulletListContainer ullist-style-type:disc;.css-1pzprxn-BulletListContainer ollist-style-type:decimal;

.css-18mjolk-ComponentWrappermargin:1.5rem 0;max-width:50rem;

.css-1hmhv5t-Placeholderposition:relative;display:block;padding-bottom:111.09374999999999%;background-color:#EEEEEE;.css-1hmhv5t-Placeholder imgoverflow:hidden;position:absolute;top:0;right:0;bottom:0;left:0;display:-webkit-box;display:-webkit-flex;display:-ms-flexbox;display:flex;-webkit-box-pack:center;-webkit-justify-content:center;-ms-flex-pack:center;justify-content:center;-webkit-align-items:center;-webkit-box-align:center;-ms-flex-align:center;align-items:center;width:100%;height:100%;object-fit:cover;

Moon graphic

.css-1ix1qms-Placeholderposition:relative;display:block;padding-bottom:0.16025641025641024%;background-color:#EEEEEE;.css-1ix1qms-Placeholder imgoverflow:hidden;position:absolute;top:0;right:0;bottom:0;left:0;display:-webkit-box;display:-webkit-flex;display:-ms-flexbox;display:flex;-webkit-box-pack:center;-webkit-justify-content:center;-ms-flex-pack:center;justify-content:center;-webkit-align-items:center;-webkit-box-align:center;-ms-flex-align:center;align-items:center;width:100%;height:100%;object-fit:cover;

Presentational white space

The 8.2-tonne Chang’e-5 spacecraft “stack” was launched from the Wenchang spaceport in southern China on 24 November (local time). It arrived above the Moon at the weekend and then set about circularising its orbit before splitting in two.

One half – a service vehicle and return module – stayed in orbit, while a lander-ascender segment was prepared for a touchdown attempt.

Chinese authorities say this lander-ascender element put down on the Moon’s surface at about 15:15 GMT (23:15 China Standard Time), after a 15-minute automated descent, controlled by the thrust of a 7,500-newton engine.

It follows China’s two previous Moon landings – Chang’e-3 in 2013 and Chang’e-4 last year. Both of these earlier missions incorporated a static lander and small rover.

A total of just under 400kg of rock and soil were retrieved by American Apollo astronauts and the Soviets’ robotic Luna programme – the vast majority of these materials coming back with the crewed missions.

But all these samples were very old – more than three billion years in age. The Mons Rümker materials, on the other hand, promise to be no more than 1.2 or 1.3 billion years old. And this should provide additional insights on the geological history of the Moon.

The samples will also allow scientists to more precisely calibrate the “chronometer” they use to age surfaces on the inner Solar System planets.

This is done by counting craters (the more craters, the older the surface), but it depends on having some definitive dating at a number of locations, and the Apollo and Soviet samples were key to this. Chang’e-5 would offer a further data point.

Reports from China suggest the effort to retrieve surface samples may last no longer than a couple of days. Any retrieved materials will be blasted back into orbit on the ascent portion of the landing mechanism, and then transferred across to the service vehicle and placed in the return module.

The orbiter will shepherd the return module to the Earth’s vicinity, jettisoning it to make an atmospheric entry and landing in the Siziwang Banner grasslands of the autonomous region of Inner Mongolia. This is where China’s astronauts also return to Earth.

“Chang’e-5 is a very complex mission,” commented Dr James Carpenter, exploration science coordinator for human and robotic exploration at the European Space Agency.

“I think it’s extremely impressive what they’re trying to do. And what I think is fascinating is you see this very systematic, step by step approach to increasing their exploration capabilities – from the early Chang’e missions to this latest one.”

.css-1uy4vn0-Containerheight:0;padding-bottom:56.25%;width:100%;color:#3F3F42;background-color:#EEEEEE;

.css-1d84lqw-LogoIconWrapperwidth:30%;padding-top:23.868243243243246%;margin:0 auto;color:#3F3F42;opacity:0.2;

Jonathan.Amos-INTERNET@bbc.co.uk and follow me on Twitter: @BBCAmos

.css-144ki52-SectionWrappermargin:1.5rem 0;padding-top:1.5rem;

Let’s block ads! (Why?)



Source link

Continue Reading

Science

Alphabet"s UK subsidiary DeepMind makes breakthrough protein shape discovery – Proactive Investors USA & Canada

Published

 on


DeepMind, a London-based subsidiary of Google’s owner Alphabet Inc, has been praised by the global scientific community after solving a 50-year-old challenge in biology. 

Its artificial intelligence system AlphaFold has figured out what shapes proteins fold into, the so-called ‘folding problem’. 

It is a major scientific breakthrough because it allows to better understand what a protein does and how it works, since its shape is closely correlated with its function. 

Proteins are the ‘building blocks of life’ because they underpin the biological processes in every living thing. 

There are currently around 200mln known proteins and another 30mln is found every year.  

Each of them has their own shape and it is often expensive and time-consuming to find their 3D composition, so we know only a fraction of the millions known to science. 

Proteins are made of amino acids, which make the protein to fold when they interact, meaning there are nearly infinite possibilities for shapes. 

AlphaFold was trained on the sequences and structures of 100,000+ proteins mapped out by scientists around the world and can now predict a protein’s shape based on the sequence of amino acids. 

As a result, scientists worldwide will have extra help in finding solutions, such as developing treatments for diseases or finding enzymes that break down industrial waste, because of the key role of proteins.  

The system was officially recognised as a solution to the issue by the biennial Critical Assessment of protein Structure Prediction, a community created in 1994 by scientists that were looking to solve the protein folding problem. 

Let’s block ads! (Why?)



Source link

Continue Reading

Science

Farrell calls for consideration of city bylaw to stop street harassment in Calgary – Calgary Herald

Published

 on


Article content continued

Some other Canadian cities have rules to deal with street harassment. In London, Ont., you can be fined for using “abusive or insulting language” in a public space.

Street harassment takes many forms, from unwanted sexual comments to whistling to flashing or groping, and it’s based on someone’s perceived gender or sexual identity. It’s a point of focus for gender equity advocates, as an example of how control tactics make people feel unsafe in public spaces.

Sagesse executive director Andrea Silverstone said Monday that street harassment can’t be dismissed as one-off comments or isolated incidents.

“It’s a structured pattern of behaviour that occurs in society that makes certain people feel unsafe,” she said. “Whether they’re women or 2SLGBTQ individuals or visible minorities feeling unsafe on the street.”

Jake Stika, executive director of Next Gen Men, said street harassment is a symptom of how boys absorb the message that being a man is about power and dominance, and they start defining their interactions that way.

Street harassment, he explains, is overwhelmingly perpetuated by men, but men are also key to stopping it.

“It’s not a women’s issue. Women are impacted by it … but what we need to do as guys is take this up as our issue,” he said. “We’re the problem, but we’re also the solution.”

Stika’s organization works to redefine manhood and masculinity with youth and community programs as part of working “upstream” to stop gender-based violence and improve men’s health and relationships.

Let’s block ads! (Why?)



Source link

Continue Reading

Trending