materiały: Ring system

Evidence: 100 • authority: 72

A ring system is a disc or torus orbiting an astronomical object that is composed of numerous solid chunks of ice, rock, and dust. In the case of giant ring systems like Saturn's, it may also contain moonlets. Ring systems are also known as planetary rings, common components of satellite systems around giant planets such as the rings of Saturn, or circumplanetary disks. But they can also occur as around other objects or as rings of interplanetary dust, such as around the Sun at distances of Mercury, Venus, and Earth, in mean motion resonance with these planets. Evidence suggests that ring systems may also be found around other types of astronomical objects, including moons and brown dwarfs.…

Evidence: 67 • authority: 72

The zodiacal light (also called false dawn when seen before sunrise) is a faint glow of diffuse sunlight scattered by interplanetary dust. Brighter around the Sun, it appears in a particularly dark night sky to extend from the Sun's direction in a roughly triangular shape along the zodiac, and appears with less intensity and visibility along the whole ecliptic as the zodiacal band. Zodiacal light spans the entire sky and contributes to the natural light of a clear and moonless night sky. A related phenomenon is gegenschein (or counterglow), sunlight backscattered from the interplanetary dust, which appears directly opposite to the Sun as a faint but slightly brighter oval glow. Zodiacal lig…

Evidence: 63 • authority: 72

Evidence: 51 • authority: 92

Evidence: 51 • authority: 72

The interplanetary dust cloud, or zodiacal cloud (as the source of the zodiacal light), consists of cosmic dust (small particles floating in outer space) that pervades the space between planets within planetary systems, such as the Solar System. This system of particles has been studied for many years in order to understand its nature, origin, and relationship to larger bodies. There are several methods to obtain space dust measurement. In the Solar System, interplanetary dust particles have a role in scattering sunlight and in emitting thermal radiation, which is the most prominent feature of the night sky's radiation, with wavelengths ranging 5–50 μm. The particle sizes of grains characte…

Evidence: 46 • authority: 72

Cosmic dust – also called extraterrestrial dust, space dust, or star dust – is dust that occurs in outer space or has fallen onto Earth. Most cosmic dust particles measure between a few molecules and 0.1 mm (100 μm), such as micrometeoroids (<30 μm) and meteoroids (>30 μm). Cosmic dust can be further distinguished by its astronomical location: intergalactic dust, interstellar dust, interplanetary dust (as in the zodiacal cloud), and circumplanetary dust (as in a planetary ring). Information on the nature of dust in locations beyond the Solar System is mostly obtained by methods of observational astronomy, such as photometry, polarimetry and infrared spectroscopy. Direct methods are also ava…

Evidence: 46 • authority: 92

Interstellar Mapping And Acceleration Probe: The NASA IMAP Mission.. NASA's Interstellar Mapping and Acceleration Probe (IMAP) mission provides extensive and well-coordinated new observations of the inner and outer heliosphere and scientific closure on two of the most important topics in Heliophysics: 1) the acceleration of charged particles and 2) the interaction of the solar wind with the local interstellar medium. These topics are intimately coupled because particles accelerated in the inner heliosphere propagate outward through the solar wind and mediate its interaction with the very local interstellar medium (VLISM). The IMAP mission is designed to address these topics, provide extensi…

Evidence: 46 • authority: 72

The rings of Uranus consist of 13 planetary rings. They are intermediate in complexity between the more extensive set around Saturn and the simpler systems around Jupiter and Neptune. The rings of Uranus were discovered on March 10, 1977, by James L. Elliot, Edward W. Dunham, and Jessica Mink. William Herschel had also reported observing rings in 1789; modern astronomers are divided on whether he could have seen them, as they are very dark and faint. By 1977, nine distinct rings were identified. Two additional rings were discovered in 1986 in images taken by the Voyager 2 spacecraft, and two outer rings were found in 2003–2005 in Hubble Space Telescope photos. In the order of increasing dis…

Evidence: 40 • authority: 72

Evidence: 40 • authority: 92

Increased and varied radiation during the Sun's encounters with cold clouds in the last 10 million years.. Recent research raises the possibility that 2-3 and 6-7 million years ago, the Sun encountered massive clouds that shrank the heliosphere -the solar cocoon protecting our solar system- exposing Earth to its interstellar environment, in agreement with geological evidence from 60 Fe and 244 Pu isotopes. Here we show that during such encounters Earth was exposed to increased radiation in the form of high-energy particles. During periods of Earth's immersion in the heliosphere, it received particle radiation that we name Heliospheric Energetic Particles (HEPs). The intensity of < 10 MeV pr…

Evidence: 35 • authority: 92

Impact Ionization Properties of Polypyrrole Nanoparticles.. Upcoming space missions flying dust impact ionization mass spectrometers will detect and analyze dust grains that are partially organic in composition. These organic components are expected to include mixtures of polycyclic aromatic hydrocarbons, heterocyclic compounds (containing oxygen, sulfur, and nitrogen), and additional functionalized condensed species. Dust impact ionization is a strongly velocity-dependent process that produces atomic and molecular ions reflective of the composition of the impacting particle. In this work, we characterize the impact ionization response of the nitrogen-bearing heterocyclic polymer polypyrrol…

Evidence: 35 • authority: 92

Biocidal Conditions in Low-Mars-Orbit Can Inactivate Bioburden on External Mars Spacecraft Surfaces and Dust Particles Within a Few Sols.. Mars Sample Return Program planning includes a series of spacecraft staged both on the Martian surface and in low-Mars-orbit (LMO). During the transfer of samples into orbit, external spacecraft surfaces might be exposed to Mars dust carried on the sample container exterior and possibly extant microbiota (if present). This study was designed to characterize the synergistic effects of LMO ultraviolet irradiation, vacuum, and solar heating on the survival of two UV-resistant and heat-tolerant bacteria, one yeast, and one fungus. The species tested were Bac…