Circa 2016
Take advantage of the next clear night and drop in on a quasar that’s currently undergoing its brightest outburst in more than 40 years.
Category: space – Page 454
Critical phenomena of emergent magnetic monopoles in a chiral magnet
Circa 2016 A great propulsion system for hoverboards and also magnetic propulsion #spacetechnology on earth 🌎😀
Phase transitions in topologically non-trivial systems are characterized by changes of topological invariants, rather than conventional order parameters. Here, the authors propose a real-space topological phase transition upon pair annihilation of emergent monopoles inherent in chiral magnet MnGe.
Scientists Found a Gap In the Universe That Defies All Logic
If you thought space already had its fair share of terrifying places, think again. We’ve discovered scorching hot planets, inhospitable gas giants with winds faster than 500 miles an hour, and blackholes themselves, but these celestial objects have characteristics.
Imagine a place that’s literally just a void, a gap in space that has absolutely nothing and stretches millions of lightyears. Scientists have found such a gap and it defies all logic, but do we know anything about this gap? Or are these questions going to be unanswered?
Assembling the first global map of lunar hydrogen
Using data collected over two decades ago, scientists from the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland, have compiled the first complete map of hydrogen abundances on the Moon’s surface. The map identifies two types of lunar materials containing enhanced hydrogen and corroborates previous ideas about lunar hydrogen and water, including findings that water likely played a role in the Moon’s original magma-ocean formation and solidification.
APL’s David Lawrence, Patrick Peplowski and Jack Wilson, along with Rick Elphic from NASA Ames Research Center, used orbital neutron data from the Lunar Prospector mission to build their map. The probe, which was deployed by NASA in 1998, orbited the Moon for a year and a half and sent back the first direct evidence of enhanced hydrogen at the lunar poles, before impacting the lunar surface.
When a star explodes, it releases cosmic rays, or high-energy protons and neutrons that move through space at nearly the speed of light. When those cosmic rays come into contact with the surface of a planet, or a moon, they break apart atoms located on those bodies, sending protons and neutrons flying. Scientists are able to identify an element and determine where and how much of it exists by studying the motion of those protons and neutrons.
Deep learning methods for designing proteins scaffolding functional sites
Current approaches to de novo design of proteins harboring a desired binding or catalytic motif require pre-specification of an overall fold or secondary structure composition, and hence considerable trial and error can be required to identify protein structures capable of scaffolding an arbitrary functional site. Here we describe two complementary approaches to the general functional site design problem that employ the RosettaFold and AlphaFold neural networks which map input sequences to predicted structures. In the first “constrained hallucination” approach, we carry out gradient descent in sequence space to optimize a loss function which simultaneously rewards recapitulation of the desired functional site and the ideality of the surrounding scaffold, supplemented with problem-specific interaction terms, to design candidate immunogens presenting epitopes recognized by neutralizing antibodies, receptor traps for escape-resistant viral inhibition, metalloproteins and enzymes, and target binding proteins with designed interfaces expanding around known binding motifs. In the second “missing information recovery” approach, we start from the desired functional site and jointly fill in the missing sequence and structure information needed to complete the protein in a single forward pass through an updated RoseTTAFold trained to recover sequence from structure in addition to structure from sequence. We show that the two approaches have considerable synergy, and AlphaFold2 structure prediction calculations suggest that the approaches can accurately generate proteins containing a very wide array of functional sites.
The authors have declared no competing interest.
Micrometeoroid Damage To James Webb Telescope Can’t Be Fixed
The widely celebrated James Webb Space Telescope has received damage to one of its mirrors from a micrometeoroid, but NASA says not to worry. — Videos from The Weather Channel | weather.com
Surprise Asteroid Mystery Unraveled — Barreling Toward Earth From Blind Spot
When asteroid 2019 OK suddenly appeared barreling toward Earth on July 25, 2019, Luisa Fernanda Zambrano-Marin and the team of astronomers at the Arecibo Observatory in Puerto Rico quickly sprang into action.
After receiving an alert, the radar scientists zoned in on the asteroid, which was approaching from Earth’s blind spot — solar opposition. Zambrano-Marin and the team had just 30 minutes to collect as many radar readings as they could. The asteroid was traveling so fast, that’s all the time she’d have it in Arecibo’s sights. University of Central Florida (UCF) manages the Arecibo Observatory for the U.S. National Science Foundation under a cooperative agreement.
Because the asteroid appeared to come out of nowhere and was traveling so fast, it made headline news.