Austria

“I always wanted to be a mental health therapist.  Ever since high school, I’ve enjoyed encouraging people and giving them hope.  But I lost my way.  I got caught in a world of addiction.  I lost ten years of my life to drugs.  I stopped when I became pregnant with my child, but by that time it was too late to go back to school.  I started working as an office manager.  I never completely lost my dream.  But I just put it on a shelf for thirty years.  Then five years ago I to…ok it off the shelf.  I heard a lady in my choir talking about how she enrolled in community college.  I drove there the very next day.  I was so nervous when I filled out the application.  I was so nervous the first day of class.  All the old voices were telling me: ‘You never finish anything.’  But I said ‘fuck you’ to the old voices.  And I started getting A’s.  On my first test, I got the only perfect score in the class.  I graduated at the age of 50.  I got my Masters at 55.  And just last night I completed a mental health first aid course.  I’m so close now.  There’s still fear there.  I used to be afraid of it never happening.  Now I’m afraid of it happening.  The old voices try to come back sometimes.  They tell me: ‘You can rest,’ or ‘You’ve earned a break.’  But I’m not stopping this time.  Somebody out there is waiting for me to finish because they need my help.“

Failing to find a single functioning stapler, the grad student struggles to keep things together.

The Beauty of Webb Telescope’s Mirrors

The James Webb Space Telescope’s gold-plated, beryllium mirrors are beautiful feats of engineering. From the 18 hexagonal primary mirror segments, to the perfectly circular secondary mirror, and even the slightly trapezoidal tertiary mirror and the intricate fine-steering mirror, each reflector went through a rigorous refinement process before it was ready to mount on the telescope. This flawless formation process was critical for Webb, which will use the mirrors to peer far back in time to capture the light from the first stars and galaxies. 

The James Webb Space Telescope, or Webb, is our upcoming infrared space observatory, which will launch in 2019. It will spy the first luminous objects that formed in the universe and shed light on how galaxies evolve, how stars and planetary systems are born, and how life could form on other planets.  

A polish and shine that would make your car jealous

All of the Webb telescope’s mirrors were polished to accuracies of approximately one millionth of an inch. The beryllium mirrors were polished at room temperature with slight imperfections, so as they change shape ever so slightly while cooling to their operating temperatures in space, they achieve their perfect shape for operations.

The Midas touch

Engineers used a process called vacuum vapor deposition to coat Webb’s mirrors with an ultra-thin layer of gold. Each mirror only required about 3 grams (about 0.11 ounces) of gold. It only took about a golf ball-sized amount of gold to paint the entire main mirror!

Before the deposition process began, engineers had to be absolutely sure the mirror surfaces were free from contaminants. 

The engineers thoroughly wiped down each mirror, then checked it in low light conditions to ensure there was no residue on the surface.

Inside the vacuum deposition chamber, the tiny amount of gold is turned into a vapor and deposited to cover the entire surface of each mirror.

Primary, secondary, and tertiary mirrors, oh my!

Each of Webb’s primary mirror segments is hexagonally shaped. The entire 6.5-meter (21.3-foot) primary mirror is slightly curved (concave), so each approximately 1.3-meter (4.3-foot) piece has a slight curve to it.

Those curves repeat themselves among the segments, so there are only three different shapes — 6 of each type. In the image below, those different shapes are labeled as A, B, and C.

Webb’s perfectly circular secondary mirror captures light from the 18 primary mirror segments and relays those images to the telescope’s tertiary mirror.

The secondary mirror is convex, so the reflective surface bulges toward a light source. It looks much like a curved mirror that you see on the wall near the exit of a parking garage that lets motorists see around a corner.

Webb’s trapezoidal tertiary mirror captures light from the secondary mirror and relays it to the fine-steering mirror and science instruments. The tertiary mirror sits at the center of the telescope’s primary mirror. The tertiary mirror is the only fixed mirror in the system — all of the other mirrors align to it.

All of the mirrors working together will provide Webb with the most advanced infrared vision of any space observatory we’ve ever launched!

Who is the fairest of them all?

The beauty of Webb’s primary mirror was apparent as it rotated past a cleanroom observation window at our Goddard Space Flight Center in Greenbelt, Maryland. If you look closely in the reflection, you will see none other than James Webb Space Telescope senior project scientist and Nobel Laureate John Mather!

Learn more about the James Webb Space Telescope HERE, or follow the mission on Facebook, Twitter and Instagram.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

Cool! Go theoretical -and experimental-physics!

Heating up exotic topological insulators

Fashion is changing in the avant-garde world of next-generation computer component materials. Traditional semiconductors like silicon are releasing their last new lines. Exotic materials called topological insulators (TIs) are on their way in. And when it comes to cool, nitrogen is the new helium.

This was clearly on display in a novel experiment at the National Institute of Standards and Technology (NIST) that was performed by a multi-institutional collaboration including UCLA, NIST and the Beijing Institute of Technology in China.

Topological insulators are a new class of materials that were discovered less than a decade ago after earlier theoretical work, recognized in the 2016 Nobel Prize in physics, predicted they could exist. The materials are electrical insulators on the inside and they conduct electricity on the outer surface. They are exciting to computer designers because electric current travels along them without shedding heat, meaning components made from them could reduce the high heat production that plagues modern computers. They also might be harnessed one day in quantum computers, which would exploit less familiar properties of electrons, such as their spin, to make calculations in entirely new ways. When TIs conduct electricity, all of the electrons flowing in one direction have the same spin, a useful property that quantum computer designers could harness.

Read more.

Researchers discover self-assembling 2D and 3D materials

Self-assembly of matter is one of the fundamental principles of nature, directing the growth of larger ordered and functional systems from smaller building blocks. Self-assembly can be observed in all length scales from molecules to galaxies. Now, researchers at the Nanoscience Centre of the University of Jyväskylä and the HYBER Centre of Excellence of Aalto University in Finland report a novel discovery of self-assembling two- and three-dimensional materials that are formed by tiny gold nanoclusters of just a couple of nanometres in size, each having 102 gold atoms and a surface layer of 44 thiol molecules. The study, conducted with funding from the Academy of Finland and the European Research Council, has been published in Angewandte Chemie.

The atomic structure of the 102-atom gold nanocluster was first resolved by the group of Roger D Kornberg at Stanford University in 2007. Since then, several further studies of its properties have been conducted in the Jyväskylä Nanoscience Centre, where it has also been used for electron microscopy imaging of virus structures. The thiol surface of the nanocluster has a large number of acidic groups that can form directed hydrogen bonds to neighbouring nanoclusters and initiate directed self-assembly.

Read more.

Building microfluidic circuits is generally a multi-day process, requiring a clean room and specialized manufacturing equipment. A new study suggests a quicker alternative using fluid walls to define the circuit instead of solid ones. The authors refer to their technique as “Freestyle Fluidics”. As seen above, the shape of the circuit is printed in the operating fluid, then covered by a layer of immiscible, transparent fluid. This outer layer help prevent evaporation. Underneath, the circuit holds its shape due to interfacial forces pinning it in place. Those same forces can be used to passively drive flow in the circuit, as shown in the lower animation, where fluid is pumped from one droplet to the other by pressure differences due to curvature. Changing the width of connecting channels can also direct flow in the circuits. This technique offers better biocompatibility than conventional microfluidic circuits, and the authors hope that this, along with simplified manufacturing, will help the technique spread. (Image and research credit: E. Walsh et al., source)

Scientists build bacteria-powered battery on single sheet of paper

Instead of ordering batteries by the pack, we might get them by the ream in the future. Researchers at Binghamton University, State University of New York have created a bacteria-powered battery on a single sheet of paper that can power disposable electronics. The manufacturing technique reduces fabrication time and cost, and the design could revolutionize the use of bio-batteries as a power source in remote, dangerous and resource-limited areas.

“Papertronics have recently emerged as a simple and low-cost way to power disposable point-of-care diagnostic sensors,” said Assistant Professor Seokheun “Sean” Choi, who is in the Electrical and Computer Engineering Department within the Thomas J. Watson School of Engineering and Applied Science. He is also the director of the Bioelectronics and Microsystems Lab at Binghamton.

“Stand-alone and self-sustained, paper-based, point-of-care devices are essential to providing effective and life-saving treatments in resource-limited settings,” said Choi.

On one half of a piece of chromatography paper, Choi and PhD candidate Yang Gao, who is a co-author of the paper, placed a ribbon of silver nitrate underneath a thin layer of wax to create a cathode. The pair then made a reservoir out of a conductive polymer on the other half of the paper, which acted as the anode. Once properly folded and a few drops of bacteria-filled liquid are added, the microbes’ cellular respiration powers the battery.

Read more.

OSKI

Pop-Outs: How the Brain Extracts Meaning From Noise

UC Berkeley neuroscientists have now observed this re-tuning in action by recording directly from the surface of a person’s brain as the words of a previously unintelligible sentence suddenly pop out after the subject is told the meaning of the garbled speech. The re-tuning takes place within a second or less, they found.

The research is in Nature Communications. (full open access)