Vol. 2 – Issue 22
Astronomy and Physics News around the World
June 17, 2012
Reported News for this Week:
1. A new theory of heat capacity
2. Science is Life: Last Transit of Venus
3. No evidence for 'knots' in space
4. Gamma-ray Outbursts Shed New Light on Pulsars
5. The optics of recycling
6. Quantum bar magnets in a transparent salt
7. Voyager 1 Breaking Through the Borders of the Solar System
8. Atoms 'split,' reassembled in new quantum physics experiment
9. Mickey Mouse on Mercury?
10.
New observations show a galaxy formed 1.1 billion years
after the Big Bang
A new theory of heat capacity
Phonon theory describes a range of different liquids
Vol. 2 – Issue 22
Physics World - Physicists in the U.K. and Russia have revived concepts first put forth in the
1940s to develop a new theory of the heat capacity of liquids. While physicists have a good
theoretical understanding of the heat capacity of both solids and gases, a general theory of the
heat capacity of liquids has remained elusive. Published in Scientific Reports, an open-access
journal published by the Nature Publishing Group, the new "phonon theory of liquid
thermodynamics" rests upon an expression for the energy of a liquid in terms of its
temperature and three parameters — the liquid's coefficient of expansion, and its Debye and
Frenkel frequencies. The researchers say that the theory covers both the classical and quantum
regimes, and has successfully predicted the heat capacity of 21 different liquids ranging from
metals to noble and molecular liquids. MORE
Science is Life: Last Transit of Venus
The Source - A nice article about the last transit of Venus of June 06, 2012… MORE
Vol. 2 – Issue 22
No evidence for 'knots' in space
University College of London - As the Universe cooled it underwent a series of phase
transitions, analogous to water freezing into ice. Many transitions cannot occur consistently
throughout space, giving rise in some theories to imperfections in the structure of the cooling
material known as cosmic textures or "knots." Cosmic textures can be identified by looking at
radiation from the cosmic microwave background. If produced in the early Universe, textures
would interact with photons from the CMB to leave a set of characteristic hot and cold spots. A
2007 study on a small piece of the sky provided a tantalizing hint that a feature of the CMB
called the "Cold Spot" could be due to cosmic texture. But in the first search for textures on the
full sky using NASA's Wilkinson Microwave Anisotropy Probe satellite, a team of researchers
found no evidence for such cosmic textures. Their result, published in Physical Review Letters,
places the best limits available on theories that produce textures, ruling out at 95 percent
confidence theories that produce more than six detectable textures on our sky. MORE
Vol. 2 – Issue 22
Gamma-ray Outbursts Shed New Light on Pulsars
Researchers using the Large Area Telescope onboard the Fermi Gamma-ray Space Telescope
have developed a new method to detect a special class of stellar remnant, known as pulsars. A
pulsar is a special type of neutron star, which spin hundreds of times per second. When the
intense spin is combined with beams of energy caused by intense magnetic fields, a
“lighthouse” pulse is generated. When the “lighthouse” beam sweeps across Earth’s field of
view, the object is referred to as a pulsar.
Led by Matthew Kerr (Kavli Institute for Particle Astrophysics and Cosmology), and Fernando
Camilo (Columbia University), a research team recently announced a new method for detecting
pulsars. How will Kerr’s research help astronomers better understand (and locate) these small,
elusive stellar remnants?
(...)
Read the rest of Gamma-ray Outbursts Shed New Light on Pulsars (308 words)
Vol. 2 – Issue 22
The optics of recycling
Optical engineers at TOMRA assembled around a test bench in the lab. From left: Tord
Bjørnevaagen Brandsæter, Andreas Nordbryhn, Marco Schade and Hans Einar Øverjordet.
Optics and Photonics News - Optical technologies, including laser scanning and spectroscopy,
can be used to identify and sort recyclable materials in a way that makes efficient use of
available natural resources and helps to reduce fossil fuel consumption — all in a cost-effective
manner. MORE
Quantum bar magnets in a transparent salt
Vol. 2 – Issue 22
University College of London - An international team of researchers have discovered a
transparent LiErF4 salt where they could image all the atomic spins in a layered sample. The
transparent salt is the perfect material to see what's going on at the quantum level for a dense
collection of tiny bar magnets. The researchers found that the spins are parallel within pairs of
layers, while for adjacent layer pairs, they are antiparallel, as large bar magnets placed adjacent
to each other would be. The team was also able to follow the magnetism as function of
quantum phase transition under an external magnetic field. This new model system is a test
bed for understanding frustrated dipolar magnetic interactions. The report is published in
Science. MORE
Voyager 1 Breaking Through the Borders of the Solar System
Vol. 2 – Issue 22
After almost 35 years traveling at over 35,000 mph, the venerable (and still operational!)
Voyager 1 spacecraft is truly breaking through to the other side, crossing the outermost
boundaries of our solar system into interstellar space — over 11 billion miles from home.
(...)
Read the rest of Voyager 1 Breaking Through the Borders of the Solar System (452 words)
Atoms 'split,' reassembled in new quantum physics experiment
Vol. 2 – Issue 22
A team of scientists was able to "split" an atom into its two possible spin states, up and down,
and measure the difference between them even after the atom resumed the properties of a
single state.
The Huffington Post - Physicists at the University of Bonn have "split" an atom into its two
possible spin states, up and down, and measured the difference between them even after the
atom resumed the properties of a single state. Picking up on the double-slit experiment, the
researchers fired two lasers in sequence at a single cold atom of cesium, moving it to the left or
right. Unlike splitting an atom into its constituent subatomic particles, as happens in radioactive
decay, in this case the atom was essentially splitting into a set of twins. It was in two states at
once — up and down. It is not possible to see both states at once. If one were to try to measure
the state of the atom, it would "collapse" into a single state. But when one looks at the atom at
the end of its journey, the combination of the two states can be measured. The work is
reported in the Proceedings of the National Academy of Science. MORE
Mickey Mouse on Mercury?
Vol. 2 – Issue 22
This collection of craters, shaped not unlike the iconic head of a certain cartoon mouse, was
imaged by NASA’s MESSENGER spacecraft on June 3, 2012.
All together now: C-R-A, T-E-R… M-O-U-S-Eeeeee…
(...)
Read the rest of Mickey Mouse on Mercury? (100 words)
Vol. 2 – Issue 22
New observations show a galaxy formed 1.1 billion years after the Big Bang
The Hubble Deep Field, with the location of galaxy HDF 805.1 marked. This galaxy, completely
invisible in visible light, formed 1.1 billion years after the Big Bang.
Ars Technica - Researchers have reported via Nature the submillimeter observation of HDF
805.1, an object first observed by the Hubble Deep Field Survey in 1996. HDF 805.1 is the
brightest infrared object in the survey, but the object is invisible as far as other wavelengths
that Hubble can detect. Without other data, astronomers could not determine the size of, or
distance to, HDF 805.1. The new observations made using the Jansky Very Large Array now
allows astronomers to determine the location of HDF 805.1 It corresponds to a bright source
about 12.6 billion light years away, meaning the object formed only 1.1 billion years after the
Big Bang. Observations suggest that HDF 805.1 is a galaxy with surprisingly high star formation
rate. While HDF 805.1 is not the earliest galaxy ever seen, it certainly has a higher star
formation rate than known galaxies of similar reshift. Moreover it is a vexing mystery as to
where such an early galaxy could have gotten so much of the presumed dust that hides it from
Hubble at visible-light wavelengths. MORE
Vol. 2 – Issue 22