7 Milky Way galaxy is warped and twisted, not flat - BBC News - Canadanewsmedia
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7 Milky Way galaxy is warped and twisted, not flat – BBC News



Our galaxy, the Milky Way, is “warped and twisted” and not flat as previously thought, new research shows.

Analysis of the brightest stars in the galaxy shows that they do not lie on a flat plane as shown in academic texts and popular science books.

Astronomers from Warsaw University speculate that it might have been bent out of shape by past interactions with nearby galaxies.

The new three dimensional map has been published in the journal Science.

The popular picture of the Milky Way as a flat disc is based on the observation of 2.5 million stars out of a possible 2.5 billion. The artists’ impressions are therefore rough approximations of the truer shape of our galaxy, according to Dr Dorota Skowron of Warsaw University.

“The internal structure and history of the Milky Way is still far from being understood, in part because it is extremely difficult to measure distances to stars at the outer regions of our galaxy,” she said.

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To gain a more accurate picture, Dr Skowron and her colleagues measured the distances of some of the brightest stars in the Milky Way, called Cepheid variable stars. These are massive young stars that burn hundreds, if not thousands, of times brighter than our own Sun. They can be so bright that they can be observed at the very edge of the galaxy.

Not only that, they also pulsate at regular intervals at a rate that is directly related to their brightness.

This enables astronomers to calculate their distance with great precision.

Most of the stars were identified by the Optical Gravitational Lensing Experiment (OGLE) at Las Campanas Observatory (LCO) in Chile’s southern Atacama Desert. Przemek Mroz, a member of the OGLE team, said that the results were surprising.

“Our results show that the Milky Way Galaxy is not flat. It is warped and twisted far away from the galactic centre. Warping may have happened through past interactions with satellite galaxies, intergalactic gas or dark matter (invisible material present in galaxies about which little in known).”

The Polish results support an analysis of Cepheid variable stars published in February in Nature Astronomy journal by astronomers from Macquarie University in Australia and the Chinese Academy of Sciences.

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UBC student builds AI voice-controller for brother's wheelchair – CBC.ca




An engineering physics student at the University of British Columbia has invented a voice-operated wheelchair for his brother, who suffers from Duchenne muscular dystrophy. 

Michael Ko doesn’t have a background in programming or electrical engineering. Instead, Ko says he relied mainly on YouTube videos to build the chair’s controller, which responds to his brother’s voice.

“He’s my brother. I think that’s the main driving force behind it,” Ko said.

“I always see him as a guy with perseverance, never giving up. And that’s the person I want to be as well.”

Michael’s brother Daniel, 28, has struggled with the muscle-wasting disease for years. He began using a wheelchair when he was eight.

Daniel Ko has Duchenne muscular dystrophy and has used a wheelchair since he was 8. (CBC)

Seeing his brother struggle pushed Michael to do more to help. 

Daniel Ko used to use a voice-activated program, Google Assistant, to help get around, but in 2017 surgery damaged his vocal chords and the software was no longer able to recognize his commands.

Most voice-recognition software can no longer interpret Daniel’s speech, which is often interrupted mid-word by having to take a breath. 

“That’s when I decided I really wanted to help him,” said Michael Ko. 

To do so, Michael decided to build his own voice recognition software, which could then help operate Daniel’s wheelchair. 

The artificial intelligence voice-controller that Michael Ko built helps his brother, Daniel Ko, use his wheelchair. (Paul Joseph/UBC)

It has taken Michael a lot of trial and error — and a few exploding electrical components — to create the right device. But now Daniel can operate his wheelchair with a few simple commands that are easier to pronounce.

“At first I thought it was impossible that an engineer would be able to do this but now were practicing and the voice recognition is getting better and better,” Daniel Ko said. 

Michael called his device Ava, named after one of the characters in the two brothers’ favourite movie, WALL-E.

“I wanted to base it off of that because the robots in WALL-E, they help humanity,” Michael said. “I wanted to transfer that same message that these AI [artificial intelligence] devices … can really help us in the future as well.”

As well as learning about software and electrical circuits, Michael says the project has taught him other valuable lessons as well. 

“What it’s really taught me is if you have a passion for something, if you have a drive for something then nothing is really impossible,” he said. 

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NASA news: Space engineer proposes accelerator propelling craft 'close to light speed' – Express.co.uk




The NASA Marshall Space Flight Centre engineer has advanced an alternative to traditional fuel for propelling rockets through space. This is a huge, helix-shaped engine powered by a particle accelerator. Dr Burns describes the controversial and highly experimental device as a “helical engine.”

The Marshall Space Flight Centre Director proposed the idea in a series of slides published to the space agency’s Technical Reports server.

He wrote: “This in-space engine could be used for long-term satellite station-keeping without refuelling.

“It could also propel spacecraft across interstellar distances, reaching close to the speed of light.”

The design builds upon a simple experiment used to describe genius scientist Isaac Newton’s third law of motion that every action has an equal and opposite reaction.

READ MORE: Dashcam fireball footage shows space rock hurtle above Alberta

A weight moving along a straight rod will only cause the box it is in to move back and forth along a frictionless surface: there is no forward acceleration.

Instead, Dr Burns proposes pushing a particle accelerator – rather than a weight – back and forth along a helix, with the mass increasing as it moves in the forward direction and decreasing as it bounces backward.

This way, when the rotating ion ring hits the front of the compartment, it produces a forward acceleration.

The NASA scientist suggests if his helical engine is provided with enough time and power, it could reach potentially extraordinary speeds aided with a particle accelerator.

READ MORE: This is what would happen if an asteroid hits Earth

The idea is admittedly controversial, with many in the field extremely sceptical of the idea.

Dr Burns admitted to New Scientist: “I’m comfortable with throwing it out there.

“If someone says it doesn’t work, I’ll be the first to say, it was worth a shot.”

First, the design would only be able to work up enough momentum in space, a completely frictionless environment.

READ MORE: NASA chief reveals nuclear ‘game changer’

Were it on Earth, it would require a ton of power—about 125 megawatts, enough energy to power a small city — to achieve just one newton of energy, the same amount of force it takes to type on a keyboard.

The helical particle accelerator would additionally need to be huge.

Dr Burns believes that in order to create actual momentum, it would have to be approximately 65ft (20m) long and 40ft (13m) across.

For reference, the International Space Station (ISS) is almost 330ft (100m) in length.

As Dr Burns suggests in the proposal, this would make it a good option for powering large spacecraft.

There are a number of issues that make his engine designs difficult to employ in space.

The greatest of which is the engine is extremely inefficient and will likely violate the laws of the conservation of momentum.

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NASA engineer invents physics-breaking new space engine – Newshub





It doesn’t look like this, but this is what it might let us do.

Photo credit: Getty

Star Trek‘s Montgomery Scott famously said “ye cannot change the laws of physics”, but a real-life space engineer says he might have just done that.

David Burns of NASA’s Marshall Space Flight Center in Alabama has unveiled what he’s calling the ‘helical engine’, which could potentially power flights across space without using any fuel at all.

There’s just one small problem – it breaks the laws of physics as we know them.

“I’m comfortable with throwing it out there,” Burns told magazine New Scientist. “If someone says it doesn’t work, I’ll be the first to say it was worth a shot.”

The simple version of how the helical engine works – or doesn’t work – is like this: a ring inside a box is sprung in one direction, the box recoiling in the other, just as Isaac Newton’s laws of motion say they should.

“When the ring reaches the end of the box, it will bounce backwards, and the box’s recoil direction will switch too,” New Scientist explains.

A simplified version of the engine.

A simplified version of the engine.

Photo credit: David Burns/NASA

But if the box and ring are travelling near the speed of light, Albert Einstein’s Theory of Relativity says as the ring approaches the front end of the box it will increase in mass because it’s going faster than when it’s going backwards – so it’ll hit harder, resulting in forward momentum. 

The actual engine itself will use a particle accelerator and ion particles, but that’s the basic gist. 

“Chemical, nuclear and electric propulsion systems produce thrust by accelerating and expelling propellants,” Burns’ paper reads. “Deep space travel is often a trade-off between thrust and large propellant storage tanks that eventually limit performance. The objective of this paper is to introduce and examine a unique engine that uses a closed-cycle propellant.”

According to Burns it could produce a forward thrust up to 99 percent the speed of light without breaking Einstein’s rules, but totally breaching Newton’s third law of motion – that an action always has an opposite and equal reaction.

There are other hurdles to overcome too – it would have to be 200m long and 12m wide to work, and would only operate effectively in the frictionless environment of deep space.

David Burns.

David Burns.

Photo credit: NASA

Burns isn’t worried if it turns out not to work at all, like others’ attempts at fuel-free propulsion, such as the microwave-powered EM drive. 

“I know that it risks being right up there with the EM drive and cold fusion,” he told New Scientist.

“But you have to be prepared to be embarrassed. It is very difficult to invent something that is new under the sun and actually works.”

Burns’ full paper can be read online here.


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