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Topic Review
Vigil (Spacecraft)
Vigil, formerly known as Lagrange, is a planned solar weather mission by the European Space Agency (ESA). It envisions two spacecraft to be positioned at Lagrangian points L1 and L5. Monitoring space weather includes events such as solar flares, coronal mass ejections, geomagnetic storms, solar proton events, etc. Monitoring would help predict arrival times at the Earth and any potential effect on infrastructure. The Vigil spacecraft are anticipated to launch in the mid 2020s. On 17 May 2021, ESA began soliciting design concept studies from various European industrial and scientific consortiums for the mission. A final design will be selected after approximately 18 months, in late 2022. Simultaneously, the ESA announced the No-Name Mission contest to replace the placeholder Lagrange name. The winning name, Vigil, was announced on 10 February 2022.
  • 516
  • 10 Oct 2022
Topic Review
Microscopium
Microscopium is a small and faint constellation located in the southern celestial hemisphere. It was first introduced by the French astronomer Nicolas Louis de Lacaille during the 18th century, who named it in honor of the microscope, reflecting the era's burgeoning interest in scientific instrumentation. Despite its modest visibility, it contains several notable celestial objects, including a few galaxies and a planetary nebula.
  • 515
  • 15 Mar 2024
Topic Review
Standard Electrode Potential
In electrochemistry, standard electrode potential [math]\displaystyle{ E^\ominus }[/math], or [math]\displaystyle{ E^\ominus_{red} }[/math], is a measure of the reducing power of any element or compound. The IUPAC "Gold Book" defines it as: "the value of the standard emf (electromotive force) of a cell in which molecular hydrogen under standard pressure is oxidized to solvated protons at the left-hand electrode".
  • 515
  • 06 Oct 2022
Topic Review
Magnetic Force Microscopy on Nanofibers
Magnetic force microscopy is a magnetic characterization method of samples usually with a maximum of a few ten nanometers surface roughness. It works by measuring an atomic force microscopy (AFM) image of the surface topography of a sample, followed by lifting the probe to avoid short-range van der Waals interactions between the tip and sample and instead measuring the long-range magnetic interactions. In addition to this simplest form of magnetic force microscopy (MFM), there are more sophisticated ones, including frequency-modulated Kelvin probe force MFM, dynamic magneto-electric force microscopy, phase-locked loop methods, and even measurements in different environments, e.g., in liquids, that have been shown.
  • 514
  • 10 Nov 2021
Topic Review
Five Hundred Meter Aperture Spherical Telescope
The Five-hundred-meter Aperture Spherical radio Telescope (FAST; Chinese: 五百米口径球面射电望远镜), nicknamed Tianyan (天眼, lit. "Heavenly Eye" or "The Eye of Heaven") is a radio telescope located in the Dawodang depression (大窝凼洼地), a natural basin in Pingtang County, Guizhou Province, southwest China. It consists of a fixed 500 m (1,600 ft) diameter dish constructed in a natural depression in the landscape. It is the world's largest filled-aperture radio telescope, and the second-largest single-dish aperture after the sparsely-filled RATAN-600 in Russia. It has a novel design, using an active surface made of metal panels that can be tilted by a computer to help change the focus to different areas of the sky. The cabin containing the feed antenna suspended on cables above the dish is also moved using a digitally-controlled winch by the computer control system to steer the instrument to receive from different directions. Construction on the FAST project began in 2011 and it achieved first light in September 2016. It is currently undergoing testing and commissioning. It observes at wavelengths of 10 cm to 4.3 m.:11 The telescope made its first discovery of two new pulsars in August 2017, barely one year after its first light. The new pulsars PSR J1859-01 and PSR J1931-02, which are also referred to as FAST pulsar #1 and #2 (FP1 and FP2), were detected on 22 and 25 August and are 16,000 and 4,100 light years away, respectively. They were independently confirmed by the Parkes Observatory in Australia on 10 September. The telescope had discovered 44 new pulsars by September, 2018.
  • 514
  • 14 Oct 2022
Topic Review
Jpsi Meson
The J/ψ (J/psi) meson /ˈdʒeɪ ˈsaɪ ˈmiːzɒn/ or psion is a subatomic particle, a flavor-neutral meson consisting of a charm quark and a charm antiquark. Mesons formed by a bound state of a charm quark and a charm anti-quark are generally known as "charmonium". The J/ψ is the most common form of charmonium, due to its spin of 1 and its low rest mass. The J/ψ has a rest mass of 3.0969 GeV/c2, just above that of the ηc (2.9836 GeV/c2), and a mean lifetime of 7.2×10−21 s. This lifetime was about a thousand times longer than expected. Its discovery was made independently by two research groups, one at the Stanford Linear Accelerator Center, headed by Burton Richter, and one at the Brookhaven National Laboratory, headed by Samuel Ting of MIT. They discovered they had actually found the same particle, and both announced their discoveries on 11 November 1974. The importance of this discovery is highlighted by the fact that the subsequent, rapid changes in high-energy physics at the time have become collectively known as the "November Revolution". Richter and Ting were awarded the 1976 Nobel Prize in Physics.
  • 514
  • 29 Nov 2022
Topic Review
Chirality
A chiral phenomenon is one that is not identical to its mirror image (see the article on mathematical chirality). The spin of a particle may be used to define a handedness, or helicity, for that particle, which, in the case of a massless particle, is the same as chirality. A symmetry transformation between the two is called parity transformation. Invariance under parity transformation by a Dirac fermion is called chiral symmetry.
  • 513
  • 27 Oct 2022
Topic Review
Bio-Photonic Cavities
An eco-friendly approach to usual optical cavities, in which an electromagnetic radiation can release energy to matter by interacting with its molecular or atomic structure. Based on bio-inspired and biodegradable meta-surfaces, able to behave as a resonator for light, their optical response can be engineered at will to accomplish a particular optical task.  
  • 513
  • 24 Nov 2021
Topic Review
Mid-Infrared External Cavity Quantum Cascade Lasers
External cavity quantum cascade lasers (ECQCLs) in the mid-infrared band have a series of unique spectral properties, which can be widely used in spectroscopy, gas detection, protein detection, medical diagnosis, free space optical communication, and so on, especially wide tuning range, the tuning range up to hundreds of wavenumbers; therefore, ECQCLs show great applications potential in many fields. 
  • 512
  • 29 Nov 2022
Topic Review
Low-energy electron Damage to DNA
The complex physical and chemical reactions between the large number of low-energy (0-30 eV) electrons (LEEs) released by high energy radiation interacting with genetic material can lead to the formation of various DNA lesions such as single strand breaks (SSBs), crosslinks (CLs), base modifications, double strand breaks (DSBs) and other clustered lesions.
  • 512
  • 29 Jul 2021
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