In a series of media opportunities Wednesday, Aug. 26, through Friday, Aug. 28, NASA experts will present an up-to-date global outlook on current conditions and future projections of sea level rise.
Colorful Calendar Celebrates 12th Anniversary of NASA’s Spitzer
Relive the highlights of NASA’s Spitzer Space Telescope mission with a new digital calendar.
Evidence for Astrophysical Muon Neutrinos from the Northern Sky with IceCube
Author(s): M. G. Aartsen et al. (IceCube Collaboration)
Using Earth as a neutrino filter, the IceCube neutrino experiment strengthens its claim that it has detected neutrinos from powerful astrophysical accelerators outside our Galaxy.

[Phys. Rev. Lett. 115, 081102] Published Thu Aug 20, 2015
The tumultuous heart of our Galaxy
This new image of powerful remnants of dead stars and their mighty action on the surrounding gas from ESA’s XMM-Newton X-ray observatory reveals some of the most intense processes taking place at the centre of our galaxy, the Milky Way.
Scientists think “planetary pebbles” were the building blocks for the largest planets
The study shows that pebble accretion can produce the observed structure of the solar system as long as the pebbles formed slowly enough that the growing gas giant planets have time to gravitationally interact with one another.
Mars rover moves onward after “Marias Pass” studies
Curiosity investigated a geological contact zone and rocks that are unexpectedly high in silica and hydrogen content.
NASA: California Drought Causing Valley Land to Sink
A new NASA report shows land in California’s San Joaquin Valley is sinking faster than ever as Californians continue pumping groundwater in response to the historic drought.
NASA: There is No Asteroid Threatening Earth
NASA scientists provide real science to debunk wild Internet rumors about an alleged September asteroid impact.
Observation of a New Narrow Axial-Vector Meson a_{1} (1420)
Author(s): C. Adolph et al. (COMPASS Collaboration)A new axial-vector meson is observed during the diffractive reaction of pions on a hydrogen target.[Phys. Rev. Lett. 115, 082001] Published Wed Aug 19, 2015
Secret of Rosetta’s cool
Technology image of the week: what look like Venetian blinds have been crucial to keep Rosetta’s temperature regulated
Solar system formation doesn’t mean a thing without that spin
New modeling shows that the supernova shock wave that helped form the Sun also could be responsible for the spin of our solar system.
ESA’s next astronaut to go into space arrives at launch site
ESA astronaut Andreas Mogensen, Soyuz spacecraft commander Sergei Volkov and Kazakh cosmonaut Aidyn Aimbetov arrived in Baikonur, Kazakhstan, yesterday. This is their last destination before heading to the International Space Station in th…
Technology CubeSat hitch-hiker on today’s HTV launch

Today’s HTV supply launch from Japan to the International Space Station also marks the arrival in orbit of one of ESA’s smallest missions yet – a CubeSat which will test miniaturised technologies for space, set to be followed by many more in coming years.
Cosmic fire
Human spaceflight and operations image of the week: aurora over Concordia research station in Antarctica
Linear halogen bulb as a powerful light source for physics experiments
The paper describes the usage of a conventional lamp equipped with a linear halogen bulb for physics
experiments. The irradiance gain and limitation of spectral resolution are treated in detail
theoretically and verified experimentally. The analysis …
Stability of vertical and horizontal axis Levitrons
The stability of the new horizontal axis Levitron 3 is compared with that of the vertical axis
device. The rotation frequency ranges are similar because they are determined by the same
precessional micro-trap, for which some theory is given. But the …
NASA Mars Rover Moves Onward After ‘Marias Pass’ Studies
After taking a low-angle selfie at its latest drilling site, NASA’s Curiosity Mars rover has departed the area called “Marias Pass,” where it had been working since May.
Send Your Name to Mars on NASA’s Next Red Planet Mission
Mars enthusiasts can participate in NASA’s journey to Mars by adding their names to a silicon microchip headed to Mars aboard NASA’s InSight Mars lander, scheduled to launch next year.
New Area Law in General Relativity
Author(s): Raphael Bousso and Netta Engelhardt
A relation between the area of a novel class of surfaces and the thermodynamic entropy has been proven, extending the results of Hawking’s 1971 area theorem.

[Phys. Rev. Lett. 115, 081301] Published Tue Aug 18, 2015
Formation of Shear Bands in Drying Colloidal Dispersions
Author(s): Pree-Cha Kiatkirakajorn and Lucas GoehringExperiments explain why solidifying colloids sometimes form zigzagging stripes as they dry.[Phys. Rev. Lett. 115, 088302] Published Tue Aug 18, 2015
LADEE spacecraft finds neon in lunar atmosphere
The mission confirms that the Moon’s exosphere is made up of mostly helium, argon, and neon.
Dark energy survey finds more celestial neighbors
New dwarf galaxy candidates could mean our sky is more crowded than we thought.
Mirror, mirror…
Space Science Image of the Week: Mirrors like these will help JWST look back 13.5 billion years to see the first stars and galaxies forming.
Celestial firework marks nearest galaxy collision
The newly discovered ring galaxy, dubbed Kathryn’s Wheel, is seven times closer than anything similar found before.
First use of ISS astronaut pictures for light pollution studies
This study not only includes the well-known signatures of cities and streets, but also the effects of faint indirectly scattered light.
Hydrodynamics Beyond the Gradient Expansion: Resurgence and Resummation
Author(s): Michal P. Heller and Michał Spaliński
The method of resurgence used in quantum field theories can address foundational aspects of relativistic hydrodynamics and its applicability to systems having large flow gradients.

[Phys. Rev. Lett. 115, 072501] Published Fri Aug 14, 2015
Week In Images
Our week through the lens: 10-14 August 2015
Hubble finds supernovae in “wrong place at wrong time”
In a complicated mystery of double star systems, merging galaxies, and twin black holes, astronomers are explaining a series of unusual supernovae found beyond the typical confines of their galaxies.
Cassini to Make Last Close Flyby of Saturn Moon Dione
NASA’s Cassini spacecraft will zip past Saturn’s moon Dione on Monday, Aug. 17 — the final close flyby of this icy satellite during the spacecraft’s long mission.
Myanmar inundated
The Copernicus Emergency Management Service is using radar images from Sentinel-1A to map the devastating flood in Myanmar
Rosetta’s big day in the Sun

ESA’s Rosetta today witnessed Comet 67P/Churyumov–Gerasimenko making its closest approach to the Sun. The exact moment of perihelion occurred at 02:03 GMT this morning when the comet came within 186 million km of the Sun.
Four-Dimensional Entropy from Three-Dimensional Gravity
Author(s): S. CarlipThe entropy of a black hole in loop quantum gravity is computed. The four-dimensional boundary term, that must be added to the loop quantum gravity action due to the presence of a black hole, maps to gravity in three dimensional spa…
Gravity and the Stability of the Higgs Vacuum
Author(s): Philipp Burda, Ruth Gregory, and Ian G. Moss
In some models, primordial black holes would have acted as seeds of Higgs vacuum decay reducing the Universe’s lifetime from trillions of years to fractions of a second. These regions of parameter space are thus ruled out.

[Phys. Rev. Lett. 115, 071303] Published Thu Aug 13, 2015
Astronomers discover “young Jupiter” exoplanet
The new planet, discovered using the Gemini Planet Imager, is a million times fainter than its parent star and shows the strongest methane signature ever detected on an alien world.
Corrected sunspot history suggests climate change since the Industrial Revolution not due to natural solar trends
After uncovering a major calibration error, scientists show that the newly corrected sunspot numbers now provide a homogenous record of solar activity dating back some 400 years.
Measurement of Maxwell’s displacement current
The measurement of Maxwell’s displacement current has remained a veritable challenge. Here we
present a novel approach that allows a detailed verification in a lecture hall-type experiment.
Spectra generated by a non-central generalized Kratzer potential and explicit expressions for expectation values of r s in N -dimensions
Analytical solutions of the N -dimensional non-relativistic wave equation with the non-central
generalized Kratzer potential with arbitrary angular momentum have been investigated within the
framework of the asymptotic iteration method. In hyperspher…
On time-dependent perturbation theory in matrix mechanics and time averaging
The time-dependent quantum perturbation theory developed by Born, Heisenberg and Jordan in 1926 is
revisited. We show that it not only reproduces the standard theory formulated in the interaction
picture, but also allows one to construct more accurat…
Gecko Grippers Moving On Up
Geckos have inspired a technology to make things stick together in space.
Observation of J/ψp Resonances Consistent with Pentaquark States in Λ_{b}^{0} →J/ψK^{−} p Decays
Author(s): R. Aaij et al. (LHCb Collaboration)A new type of particle containing five quarks has been observed by the LHCb experiment.[Phys. Rev. Lett. 115, 072001] Published Wed Aug 12, 2015
X-Ray Diffraction of Solid Tin to 1.2 TPa
Author(s): A. Lazicki, J. R. Rygg, F. Coppari, R. Smith, D. Fratanduono, R. G. Kraus, G. W. Collins, R. Briggs, D. G. Braun, D. C. Swift, and J. H. Eggert
Solid tin has been compressed to a record high pressure without undergoing melting.

[Phys. Rev. Lett. 115, 075502] Published Wed Aug 12, 2015
Trusty, not rusty, pipelines owe a debt to space
When a Dutch company working on soil pollution teamed up with ESA to build a better, bacteria-based air filter for space, they also created the foundation for a new way of keeping iron pipelines from corroding in the ground.
Ariane 6 and Vega C begin development

Today, ESA signed contracts for the development of the Ariane 6 new‑generation launcher, its launch base and the Vega C evolution of the current small launcher.
Oxymoronic black hole provides clues to growth
By studying the lightest supermassive black hole found to date, scientists hope to better understand of such objects of different sizes grow.
Rosetta sees comet’s fireworks display ahead of perihelion
The dramatic event on Comet 67P/Churyumov-Gerasimenko was so powerful that it even pushed away the incoming solar wind.
Space’s Top 40: How CubeSats are Revolutionizing Radio Science
Next time you tune in to public radio or the hottest Top 40 radio station, you’ll be using some of the same tools NASA uses to unravel the mysteries of the universe.
Rosetta Comet Outburst Captured
A dramatic outburst from Rosetta’s target comet is recorded by several instruments, including the Double Focusing Mass Spectrometer, which uses NASA-built electronics.
Lightly thru space

Human spaceflight and operations image of the week: ESA’s Cebreros deep-space tracking station reflecting environmentally friendly light
Astronomers discover a 10th transiting “Tatooine”
With the number of known circumbinary exoplanets now at 10, astronomers can begin to compare different systems and look for trends.
Comet’s firework display ahead of perihelion

In the approach to perihelion over the past few weeks, Rosetta has been witnessing growing activity from Comet 67P/Churyumov–Gerasimenko, with one dramatic outburst event proving so powerful that it even pushed away the incoming solar wind.
Then and now
Space science image of the week: Rosetta’s view upon arrival at the comet, on 6 August 2014, and exactly one year later
Optics laboratory extensions
Most of the optics experiments done in beginning or advanced labs have ultrasonic analogs which can
be used to demonstrate much of what can be done in the optics labs. These analogs can be used as a
substitute for the corresponding optics experiments…
Finite size effect on classical ideal gas revisited
Finite size effects on classical ideal gas are revisited. The micro-canonical partition function for
a collection of ideal particles confined in a box is evaluated using Euler?Maclaurin?s as well as
Poisson’s summation formula. In Poisson’s summation…
A note on the Fermi energy of an ideal Fermi gas trapped under a generic power law potential in d -dimension
The average energy per fermion in the case of a Fermi gas with any kinematic characteristic, trapped
under the most general power law potential in d -dimension has been calculated at zero temperature.
In a previous paper (Acharyya M 2010 Eur. J Phys….
Laplace equation, magnetic recording and the Karlqvist approximation
Magnetic recording head theory is based on the Karlqvist approximation to solve the Laplace equation
over a polygonal domain that originates from a magnetostatic approach to describe the magnetic field
produced by the read/write head in the recording…
Some problems in applications of the linear variational method
The linear variational method is a standard computational method in quantum mechanics and quantum
chemistry. As taught in most classes, the general guidance is to include as many basis functions as
practical in the variational wave function. However,…
NASA’s Europa Mission Team Joins Forces for the First Time
Like legendary superheroes, all space missions have origin stories. NASA’s Europa mission team recently wrote the final chapter of theirs, with their first team meeting.
One Decade after Launch, Mars Orbiter Still Going Strong
Ten years after launch, NASA’s Mars Reconnaissance Orbiter has revealed the Red Planet’s diversity and activity, and its work is far from over.
Nature, Chinese Pollution Offset U.S. West Ozone Gains
An expected reduction in atmospheric ozone levels over the western U.S. was offset by natural atmospheric processes and pollutants crossing the Pacific Ocean from China.
Experimental Observation of Quasicrystal Growth
Author(s): Keisuke Nagao, Tomoaki Inuzuka, Kazue Nishimoto, and Keiichi EdagawaIn situ high-resolution transmission electron microscopy has been used to spot quasicrystals in the act of growing.[Phys. Rev. Lett. 115, 075501] Published Mon Aug 10, 2015
Charting the slow death of the universe
Astronomers studying energy output in the nearby universe have confirmed that the energy produced today is only about half what it was 2 billion years ago.
Salt flat indicates some of the last vestiges of surface water on Mars
Digital terrain mapping and mineralogical analysis of the features surrounding the deposit indicate that this one-time lakebed is no older than 3.6 billion years old.
Gravitational constant appears universally constant, pulsar study suggests
The fact that scientists can see gravity perform the same in our solar system as it does in a distant star system helps confirm that the gravitational constant truly is universal.
NASA to Share the Universe with Tumblr Users
NASA is launching an official Tumblr profile that will give Tumblr users a regular dose of space in a blog-like format through text, photos, videos and more.
Week In Images
Our week through the lens: 3-7 August 2015
Hubble finds evidence of galaxy star birth regulated by black hole fountain
The discovery explains the mystery of why many elliptical galaxies in the present-day universe are not ablaze with a higher rate of star birth.
Celebrate perihelion!
Watch a replay of a Google+ Hangout with Rosetta and Philae experts held to celebrate the comet’s closest approach to the Sun
Sentinels catch traffic jam
Low water levels in the Danube river have left ships to queue close to the town of Zimnicea in Romania.
From a million miles away, NASA camera shows Moon crossing face of Earth
The DSCOVR satellite’s series of test images reveals the fully illuminated “dark side” of the Moon never visible from our planet.
In Africa, More Smoke Leads to Less Rain, NASA Shows
Agricultural fires in North Africa reduce the region’s rainfall during the dry season, according to a NASA study.
Cruise Over Ceres in New Video
Striking 3-D detail highlights a towering mountain, the brightest spots and other features on dwarf planet Ceres in a new video from NASA’s Dawn mission.
Cruise over Ceres in new video
A prominent mountain with bright streaks on its steep slopes is especially fascinating to scientists.
Year at a comet

Celebrating Rosetta’s first year at Comet 67P/Churyumov–Gerasimenko with a calendar of NavCam images
Celebrating a year at the comet

ESA’s Rosetta mission today celebrates one year at Comet 67P/Churyumov–Gerasimenko, with its closest approach to the Sun now just one week away.
Expanding the simple pendulum’s rotation solution in action-angle variables
Integration of Hamiltonian systems by reduction to action-angle variables has proven to be a
successful approach. However, when the solution depends on elliptic functions, the transformation to
action-angle variables may need to remain in implicit fo…
Expanding the simple pendulum’s rotation solution in action-angle variables
Integration of Hamiltonian systems by reduction to action-angle variables has proven to be a
successful approach. However, when the solution depends on elliptic functions, the transformation to
action-angle variables may need to remain in implicit fo…
Mechanical analog of an over-damped Josephson junction
An over-damped pendulum can be adopted as a mechanical analogue of an over-damped Josephson junction
(JJ). The basic equations leading to the driving torque versus the time average of the angular
frequency are studied. The mechanical analogue can be …
Mechanical analog of an over-damped Josephson junction
An over-damped pendulum can be adopted as a mechanical analogue of an over-damped Josephson junction
(JJ). The basic equations leading to the driving torque versus the time average of the angular
frequency are studied. The mechanical analogue can be …
Large deviations of the maximum of independent and identically distributed random variables
A pedagogical account of some aspects of extreme value statistics (EVS) is presented from the
somewhat non-standard viewpoint of large deviation theory. We address the following problem: given a
set of N independent and identically distributed (i.i.d…
Large deviations of the maximum of independent and identically distributed random variables
A pedagogical account of some aspects of extreme value statistics (EVS) is presented from the
somewhat non-standard viewpoint of large deviation theory. We address the following problem: given a
set of N independent and identically distributed (i.i.d…
Coherent scattering in non relativistic quantum mechanics
In this paper we give a pedagogical explanation of coherence effects in non relativistic scattering
processes. Coherent scattering is important not only because it is a clear manifestation of the wave
character of the interaction in these regimes, bu…
Coherent scattering in non relativistic quantum mechanics
In this paper we give a pedagogical explanation of coherence effects in non relativistic scattering
processes. Coherent scattering is important not only because it is a clear manifestation of the wave
character of the interaction in these regimes, bu…
Advanced undergraduate RC circuits: an experimentalist’s perspective
In this paper, an advanced undergraduate RC circuit is studied in two different ways. The circuit is
a typical series RC circuit with a time-varying voltage source. The temporal profile of the voltage
is an isolated, Gaussian shaped pulse. The voltag…
Advanced undergraduate RC circuits: an experimentalist’s perspective
In this paper, an advanced undergraduate RC circuit is studied in two different ways. The circuit is
a typical series RC circuit with a time-varying voltage source. The temporal profile of the voltage
is an isolated, Gaussian shaped pulse. The voltag…
New Online Exploring Tools Bring NASA Journey’s to Mars to New Generation
On the three-year anniversary of the Mars landing of NASA’s Curiosity rover, NASA is unveiling two new online tools, inviting the public to help with its journey to Mars.
Researchers Use ‘Seafloor Gardens’ to Switch on Light Bulb
How did the very first life forms on Earth get an electrical boost? New laboratory experiments offer clues.
Jupiter’s Great Red Spot: a swirling mystery
Scientists are performing laboratory studies to try to decipher what causes the giant storm’s swirl of reddish hues.
Jupiter’s Great Red Spot: a swirling mystery
Scientists are performing laboratory studies to try to decipher what causes the giant storm’s swirl of reddish hues.
Tracking a mysterious group of asteroid outcasts
A new study has traced some members of the near-Earth object population back to their likely source — the Euphrosyne family of dark asteroids in the outer asteroid belt.
First MSG-4 image

Europe’s latest weather satellite images Earth today
Ghostly remnants of galaxy interactions uncovered in nearby galaxy group
As part of a galactic archaeology study, astronomers discovered that the spatial distribution of the young stars around M81, M82, and NGC 3077 follows very closely that of their distribution of neutral hydrogen.
Neutron stars strike back at black holes in jet contest
Astronomers have discovered that some neutron stars may rival black holes in their ability to accelerate powerful jets of material to nearly the speed of light.
Tracking downunder
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Human spaceflight and operations image of the week: ESA’s New Norcia deep-space tracking station illuminated against the Australian night sky
Sackur?Tetrode equation in the lab
We present a review of some aspects related to the experimental validity of the Sackur?Tetrode
equation for the entropy of monatomic ideal gases. First, we examine the main theoretical
assumptions which underlie the statistical derivation of the equa…
Impedance function calculation for the study of waves in locally periodic arrangements
In this paper, we study theoretically the propagation of waves in locally periodic systems. To this
end, we employ a simple method based on the impedance function which is similar to the one used in
the transmission line theory. Results are presented…
Sackur–Tetrode equation in the lab
We present a review of some aspects related to the experimental validity of the Sackur–Tetrode
equation for the entropy of monatomic ideal gases. First, we examine the main theoretical
assumptions which underlie the statistical derivation of the eq…
Sound resonance in pipes with discrete Fourier transform
Sound resonance in pipes is investigated using a readily available setup consisting of a pipe,
loudspeaker, microphone, and laptop. Discrete Fourier transform is used to extract the amplitude and
phase spectra from the recorded sound enabling determi…
A simple way of approximating the canonical partition functions in statistical mechanics
We propose a simple pedagogical way of introducing the Euler–MacLaurin summation formula in an
undergraduate course on statistical mechanics. The reason is that the students may feel more
comfortable and confident if they are able to deduce the mai…
No-faster-than-light-signaling implies linear evolution. A re-derivation
There is a growing interest, both from the theoretical as well as experimental side, to test the
validity of the quantum superposition principle, and of theories which explicitly violate it by
adding nonlinear terms to the Schrödinger equation. We r…
Characterizing the movement of a falling rigid rod
In this paper we present a simple experimental set-up to study the fall of a rigid rod, which can
freely rotate around an articulated joint at the lowest point. The experimental set-up permits
preparation of a laboratory session for physics or engine…