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Category: space – Page 238

Seeking Solutions to Underwater Noise Pollution

From early in his career, Kamal Kesour understood the damaging effects of urban noise and was aware of the instrumentation used to measure and control it. He had lived in big cities, and after his PhD he went to work for an environmental consulting firm that specialized in urban noise. But it wasn’t until later, during a research position at Innovation Maritime in Canada, that he realized marine mammals can experience similarly noisy environments. This noise comes from underwater vibrations generated by shipping vessels transporting goods around the world. Kesour now has a career helping to make maritime transportation vessels less noisy.

Kesour has spent the past few years in Rimouski, Canada, at the Marine Acoustic Research Station (MARS), which lies on the banks of the St. Lawrence Estuary and is jointly led by Innovation Maritime, the Rimouski Institute of Marine Sciences, and engineering consultancy OpDAQ systems. There, he measures ambient underwater noise from ships as they pass on their way to and from the Atlantic Ocean or North America’s Great Lakes. He also conducts on-ship measurements to help pinpoint noise sources and to “fingerprint” the vibrations of individual ships. Physics Magazine caught up with Kesour to learn more about his measurements and their implications for noise pollution produced by the shipping industry.

All interviews are edited for brevity and clarity.

Space Accident Means Tardigrades May Have Contaminated The Moon

# spacebear.

Just over five years ago, on 22 February 2019, an unmanned space probe was placed in orbit around the Moon.

Named Beresheet and built by SpaceIL and Israel Aerospace Industries, it was intended to be the first private spacecraft to perform a soft landing. Among the probe’s payload were tardigrades, renowed for their ability to survive in even the harshest climates.

The mission ran into trouble from the start, with the failure of “star tracker” cameras intended to determine the spacecraft’s orientation and thus properly control its motors. Budgetary limitations had imposed a pared-down design, and while the command center was able to work around some problems, things got even trickier on 11 April, the day of the landing.

A baby star’s planet-forming disk has 3 times more water than all of Earth’s oceans

The team behind the breakthrough used the Atacama Large Millimeter/ submillimeter Array (ALMA) to zoom in on water vapor locked up in gas and dust within a protoplanetary disk surrounding the sun-like star HL Tauri, located 450 light-years away from Earth in the constellation Taurus.

“I had never imagined that we could capture an image of oceans of water vapor in the same region where a planet is likely forming,” Stefano Facchini research leader and an astronomer at the University of Milan, said in a statement. “Our results show how the presence of water may influence the development of a planetary system, just like it did some 4.5 billion years ago in our own solar system.”

Scientists just created the strongest magnetic force in the universe

You may never have heard of magnetars, but they are, in a nutshell an exotic type of neutron star whose magnetic field is around a trillion times stronger than the Earth’s.

To illustrate their strength, if you were to get any closer to a magnetar than about 1,000km (600 miles) away, your body would be totally destroyed.

Its unimaginably powerful field would tear electrons away from your atoms, converting you into a cloud of monatomic ions – single atoms without electrons– as EarthSkynotes.

Superconductivity in a van der Waals layered quasicrystal

Recent theoretical studies36,37,38 have revealed that quasicrystalline superconductors exhibit several unconventional behaviors that are typically not observed in other known superconductors in periodic and disordered systems, thus opening a new field in the research of superconductivity. Nagai36 has studied superconducting tight-binding models of Penrose and Ammann – Beenker lattices (typical two-dimensional quasicrystalline lattices) and demonstrated an intrinsic vortex pinning due to spatially inhomogeneous superconducting order parameter. Such an inhomogeneous order parameter arises from the quasicrystalline structural order, and therefore, the vortex pinning occurs without an impurity or defect. Sakai et al37. have investigated quasicrystalline superconductivity using an attractive Hubbard model on a Penrose lattice using the real-space dynamical mean-field theory. Unconventional spatially-extended Cooper pairs were formed; the sum of the momenta of the Cooper pair electrons was nonzero, in contrast to the zero total momentum of the Cooper pair in the conventional BCS superconductivity. Such a nonzero total momentum of the Cooper pair is also observed for the Fulde – Ferrell – Larkin – Ovchinnikov (FFLO) state previously proposed for periodic systems39,40,41,42. However, the unconventional Cooper pairing in the model QC is completely different from the FFLO state because the Cooper pairing occurs under no magnetic field. In addition, under a high magnetic field, a state similar to the FFLO state is formed in the model QC38. However, this state is also different from the conventional FFLO state in periodic systems and forms a fractal-like spatial pattern of the oscillating superconducting order parameter, which is compatible with the self-similar structural order that is possessed by the QCs. As mentioned above, many interesting features are theoretically expected for superconducting QCs, which are yet to be demonstrated experimentally, and the Ta1.6 Te dodecagonal QC phase in the present study offers a precious platform for it.

In conclusion, polygrain Ta1.6 Te dodecagonal QC samples were fabricated by reaction sintering. Careful phase identification of the sample was performed by electron and powder X-ray diffraction experiments and diffraction-profile simulations. The samples were subjected to electrical resistivity, magnetic susceptibility, and specific heat measurements. The results unconditionally validate the occurrence of bulk superconductivity at a \({T}_{{{{{{\rm{c}}}}}}}\) of ~1 K. This is the first example of superconductivity in thermodynamically stable QCs. These findings are expected to motivate further investigations into the physical properties of vdW layered quasicrystals as well as two-dimensional quasicrystals. In particular, the dodecagonal QC provides a valuable platform for the experimental demonstration of the unique superconductivity theoretically predicted for QCs.

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