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Roger's Equations

This blog is all about science and technology (with occasional math thrown in for fun). The goal of this blog is to try and pass on the sense of excitement and wonder I feel when I read about these topics. I hope you enjoy the posts.

Does Pluto Have a Giant Crater?

Posted July 01, 2015 8:36 AM by Roger Pink

New Horizons

It's an exciting time for space enthusiasts. The NASA probe, New Horizons, is just two weeks from its July 14th flyby of Pluto. Everyday new images arrive revealing more details of Pluto and its moons Charon, Nix, Hydra, Styx, and Kerberos (Nod to CR4 Member G.K. for possibly naming this moon). The images are already starting to surprise scientists. Charon appears to have a surprisingly dark pole. Pluto's moons* seem to tumble about chaotically. *Note - Pluto and Charon have more of a binary dwarf-planet arrangement than a traditional planet-moon arrangement. The other moons orbit the center of gravity of the Pluto-Charon binary (see image below). The center of gravity of the Pluto-Charon system is outside of the surface of Pluto.

The last month the ever improving images of Pluto have The dwarf-planet didn't seem to be completely round. At first scientists explained it was an optical illusion caused by the distance and the deconvolution method used to improve the images taken by LORRI on New Horizons. However, as the space probe gets closer and closer to Pluto, and the images sent back to us get better and better, it's starting to look like Pluto may have a gigantic crater that does indeed distort it's shape.

We wont have to wait long to find out for sure. In two weeks New Horizons will get as closer than 10,000 km to Pluto. Starting July 11th, the surfaces of Pluto and Charon will begin being mapped at 40 km (25 mile) resolution! Soon we will know for sure if the giant crater is real or some weird image processing effect. It sure looks real though in that June 29th image!

Approaching Pluto (LORRI Images)

Pluto-Charon Binary System

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June 30th and July 1st - Venus and Jupiter Conjunction

Posted June 30, 2015 11:49 AM by Roger Pink

The Two Brightest "Wanderers" Meet

The last several weeks, the two brightest planets in the night sky, Venus and Jupiter, have been inching closer to each other in the night sky. At the beginning of June they were 20 degrees apart in the sky. Tonight and tomorrow night Venus and Jupiter will be less than a degree apart, having the appearance of a bright double star in the early evening sky. Here is an article from Sky and Telescope on the conjunction.

Venus and Jupiter: Together at Last

Anyone who pays even cursory attention to the evening sky has surely noticed that the two brightest planets, Venus and Jupiter, have been drawing closer together in the west in the evening twilight. At the beginning of June, the two planets were 20° apart in the sky, about twice the width of your fist held at arm's length. Week by week, Jupiter and the stars behind it have gradually slipped lower in the evening twilight. But Venus, due to its rapid orbital motion around the Sun, has stayed high up.

The resulting slow-motion convergence is setting the stage for a dramatic sky sight. The warm-up act came on June 19th and 20th, when the planetary duo was joined by a thin and lovely crescent Moon. Farther to their upper left, and fainter, was Regulus, the alpha star of Leo. (I was texting all my friends: "Go outside. Now. Look west!") -

Article Continues Here

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Population III Stars

Posted June 28, 2015 8:09 PM by Roger Pink

Stars of the Early Universe

Scientists believe that the first generation of stars that formed after the big bang were likely very large, very hot, and consisted mostly of hydrogen, helium and perhaps a tiny bit of lithium. Why only those three elements? Because larger elements didn't exist yet. It would take the fusion within these population III stars to create the heavier elements such as oxygen, nitrogen, carbon, etc which we find throughout the more recent universe (population II and I stars).

Up until recently these stars were merely conjecture, derived from computer models based on our understanding of cosmology. Simply put, as the early universe expanded after the big bang, the quark-gluon plasma that was the whole of the universe gradually cooled forming protons and neutrons, which in turn later formed mostly hydrogen and some helium. As the universe further expanded and cooled, the hydrogen and helium started to clump together to form the first stars, population III stars.

Now it is being reported that these first generation stars might have been sighted. Here is a article about it from Science:

Astronomers spot first-generation stars, made from big bang

A team of astronomers has found the best evidence yet for the very first generation of stars, ones made only from ingredients provided directly by the big bang. Made of essentially only hydrogen and helium, these so-called population III stars are predicted to be enormous in size and to live fast and die young. Until recently, many astronomers had thought they would never be able to see such stars, because they would have all burned and died in the universe's early history-too far for us to see. But using new instruments on the world's top telescopes, the team found a uniquely bright galaxy that seems to bear all the hallmarks of containing population III stars.

"The evidence is strong. They did a careful job," says Avi Loeb, chair of Harvard University's astronomy department. Theorists predict that the clouds of gas in the early universe would have remained relatively warm from the big bang and so would resist condensing down to form stars. Mixing in a small amount of heavier elements helps gas clouds cool, because those elements are easier to ionize and so shed heat as radiation. But those heavy elements hadn't yet formed in the early universe, so stars grew to enormous sizes-hundreds or even a thousand times as big as our sun-before their cores were dense enough to spark fusion. Once they did get started, they burned fast and hot, emitting lots of ultraviolet light and burning out in a few million years. It was such burning that created the heavier elements that now populate the universe. Fusion in the cores of stars meld light atoms into heavier ones, all the carbon, oxygen, iron, and everything else needed to make dust clouds, planets, and life. These heavier elements are scattered around when a star ends its life and explodes. So all the gas that exists in the universe now has a smattering of heavier elements, which allow it to cool more easily. As a result, stars tend to be smaller, burn less brightly, and live longer than their ancient forebears.

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2 comments; last comment on 06/30/2015
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The Emerging Exoskeleton Industry

Posted June 23, 2015 9:37 AM by Roger Pink

The Future is Now (And Soon)

Every so often a remarkable, life changing device that we've anticipating for decades finally goes mainstream, often with little fanfare at the time. This is because the technology behind it developed incrementally, and without a pivotal breakthrough to point to, we tend not to notice these things. It happened with cell phones, fracking, organ transplants, computers, the internet, radio, etc. Now it's happening again with exoskeletons.

If that sounds like hyperbole, consider Claire Lomas. Claire, who was paralyzed from the waist down after a horse-riding accident in 2006, walked the 26.2 miles of the London Marathon with the aid of an exoskeleton. Remarkable, and yet this occurred in 2012 and since then the feat has been accomplished several more times by others in exoskeleton suits.

But exoskeletons are not just for medical applications. The military and industry have been looking into exoskeletons that make loads lighter or otherwise enhance human ability. For instance there is Lockheed Martin's HULC Exoskeleton. Or the Fortis Exoskeleton.

So you see, exoskeletons are already starting to appear in medical, industrial, and military applications. I've mentioned three but there are hundreds of exoskeletons being developed as we speak. Last year three exoskeleton companies went public and there are several more companies in the pipeline. The exoskeleton industry is predicted to have a compound annual growth rate of over 70% from 2015-2019.

Engineering360 Article

I recently wrote an article for Engineering360 about Exoskeletons. Here it is:

Exoskeleton Technology Takes a Step Forward

Researchers from the European Union's (EU's) Robo-Mate project presented their first prototype of an industrial exoskeleton at Fraunhofer Institute for Industrial Engineering (IAO) in Stuttgart in mid-June 2015. According to the group, the exoskeleton makes loads appear to be as much as 10 times lighter to lift. Dr. Hans Wernher van de Venn, head of the Institute of Mechatronic Systems at Zurich University of Applied Sciences and Coordinator of the Robo-Mate project, says the prototype consists of modules for the arms, the body trunk and the legs. It works by supporting the user's arms and legs as well as protecting his or her back and supporting posture. By means of motors and sensors, it reduces the effective load workers have to bear to a fraction of the actual load.

The Robo-Mate project's goal is to develop an intelligent, easy-to-maneuver, wearable exoskeleton to enhance work conditions for load workers and to ease repetitive lifting tasks in an effort to reduce work-related injuries. The project consists of 12 partners from seven European countries, including players from industry and academia.

The technology at the heart of the project involves merging human-guided manipulators with computer-controlled industrial robots. If successful, Robo-Mate industrial exoskeletons could be adopted by a range of industries where heavy or repetitive lifting is required. In time, every industry may adopt some form of exoskeleton enhancement for improved safety and performance.Skepticism about exoskeletons going mainstream may be understandable.The idea of exoskeletons has been around for a long time and the technology has always seemed right around the corner.

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13 comments; last comment on 06/26/2015
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Space-Time Crystals

Posted June 16, 2015 11:02 AM by Roger Pink

Breaking Temporal Symmetry

A normal crystal is said to break spatial symmetry because its particles line up in specific directions, rather than being regularly spaced (as they are at higher temperatures). A new concept, called a space-time crystal takes that one step further by breaking temporal symmetry. Breaking temporal symmetry simply means that an object or a collection of particles experiences some kind of systematic, repeating change over time. Of course, that could simply be a planet orbiting the sun. What makes a space-time crystal special is that it breaks temporal symmetry from it's ground state. In other words, it would take energy to stop the broken temporal symmetry. Usually the opposite is true.

It sounds bizarre, but the concept was presented by Frank Wilczek in 2012 and is being pursued by several experimental groups. Frank Wilczek won the Nobel Prize in Physics in 2004 along with David Gross and David Politzer for their discovery of asymptotic fredom in the theory of the strong interaction and is currently the Herman Feshbach Professor of Physics at MIT, so the theory has some weight behind it.

Here is a recent article on the subject:

"Time Crystals" Could Upend Physicists' Theory of Time

IN FEBRUARY 2012, the Nobel Prize-winning physicist Frank Wilczek decided to go public with a strange and, he worried, somewhat embarrassing idea. Impossible as it seemed, Wilczek had developed an apparent proof of "time crystals" - physical structures that move in a repeating pattern, like minute hands rounding clocks, without expending energy or ever winding down. Unlike clocks or any other known objects, time crystals derive their movement not from stored energy but from a break in the symmetry of time, enabling a special form of perpetual motion.

"Most research in physics is continuations of things that have gone before," said Wilczek, a professor at the Massachusetts Institute of Technology. This, he said, was "kind of outside the box." Wilczek's idea met with a muted response from physicists. Here was a brilliant professor known for developing exotic theories that later entered the mainstream, including the existence of particles called axions and anyons, and discovering a property of nuclear forces known as asymptotic freedom (for which he shared the Nobel Prize in physics in 2004). But perpetual motion, deemed impossible by the fundamental laws of physics, was hard to swallow. Did the work constitute a major breakthrough or faulty logic? Jakub Zakrzewski, a professor of physics and head of atomic optics at Jagiellonian University in Poland who wrote a perspective on the research that accompanied Wilczek's publication, says: "I simply don't know."

Now, a technological advance has made it possible for physicists to test the idea. They plan to build a time crystal, not in the hope that this perpetuum mobilewill generate an endless supply of energy (as inventors have striven in vain to do for more than a thousand years) but that it will yield a better theory of time itself.

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10 comments; last comment on 06/18/2015
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Viewing The Milky Way's Supermassive Black Hole

Posted June 11, 2015 11:12 AM by Roger Pink

Sagittarius A*

In the center of the Milky Way there is a very bright, compact radio source. Found near the constellations Sagittarius and Scorpius in the night sky, Sagittarius A*(Sgr A*) is believed to be the location of a supermassive black hole similar to those observed to exist at the center of other galaxies.

Due to dust and gas, astronomers have been unable to observe Sgr A* in the optical spectrum. Attempts have been made to view it using radio telescopes.

Event Horizon Telescope

The Event Horizon Telescope is a project to create a large millimeter telescope array combining data from radio telescope stations from around the Earth using very-long-baseline interferometry (VLBI) to observe the immediate environment of the Milky Way's supermassive black hole Sgr A* with angular resolution comparable to the event horizon.

The group will combine existing and planned millimeter/submillimeter facilities into a high-sensitivity, high angular resolution Event Horizon Telescope. The effort will include development and deployment of submillimeter dual polarization receivers, highly stable frequency standards to enable VLBI at 230-450 GHz, higher-bandwidth VLBI backends and recorders, as well as commissioning of new submillimeter VLBI sites.

New York Times Video on the Event Horizon Telescope

Here is an excellent video discussing the Event Horizon Telescope and it's mission to observe Sgr A*

NYT Video

3 comments; last comment on 06/12/2015
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