Thursday, 10 July 2014

Missions past low Earth circle leave the assurance of the geomagnetic field

Missions past low Earth circle leave the assurance of the geomagnetic field, and travel the Van Allen cinchs. In this manner they may need to be protected against presentation to infinite beams, Van Allen radiation, or sun oriented flares. The locale between two to four Earth radii lies between the two radiation cinchs and is off and on again alluded to as the "safe zone". 

Sun oriented cells, coordinated circuits, and sensors might be harmed by radiation. Geomagnetic storms every so often harm electronic parts on rocket. Scaling down and digitization of gadgets and rationale circuits have made satellites more powerless against radiation, as the aggregate electric charge in these circuits is presently little enough in order to be practically identical with the charge of approaching particles. Hardware on satellites must be solidified against radiation to work dependably. The Hubble Space Telescope, in addition to different satellites, regularly has its sensors turned off when passing through areas of serious radiation. A satellite protected by 3 mm of aluminum in an elliptic circle (200 by 20,000 miles (320 by 32,190 km)) passing the radiation cinchs will get about 2,500 rem (25 Sv) for every year. Just about all radiation will be gotten while passing the internal cinch 

A hole between the inward and external Van Allen sashs, in some cases called safe zone or safe space, is brought on by the Very Low Frequency (VLF) waves which dissipate particles in contribute plot which comes about the increase of particles to the environment. Sunlight based upheavals can pump particles into the hole however they empty again in a matter of days. The radio waves were initially thought to be created by turbulence in the radiation cinchs, however late work by James L. Green of the Goddard Space Flight Center analyzings maps of lightning action gathered by the Microlab 1 rocket with information on radio waves in the radiation-cinch crevice from the IMAGE space apparatus recommends that they are really created by lightning inside Earth's climate. The radio waves they create strike the ionosphere at the right point to pass through it just at high scopes, where the lower finishes of the crevice approach the upper climate. These results are still under logical open deliberation. 

High Voltage Orbiting Long Tether, or Hivolt, is an idea proposed by Russian physicist V.v. Hoyt and Robert L. Forward for emptying and evacuating the radiation fields of the Van Allen radiation belts that encompass the Earth. A proposed setup comprises of an arrangement of five 100 km long leading ties conveyed from satellites, and charged to a huge voltage. This would result in charged particles that experience the ties to have their pitch plot changed, hence about whether dissolving the internal sashs. 

"A general depiction of trapped radiation is as takes after. Charged particles move in spirals around attractive field lines. The pitch point (the edge between the course of the movement of the molecule and bearing of the field line) has a low esteem at the equator and builds while the molecule moves down a field line in the heading where the attractive field quality expands. At the point when the pitch plot turns into 90 degrees, the molecule must move in the other bearing, up the field lines, until the methodology rehashes itself at the flip side. The molecule is consistently reflected at the two mirror focuses — it is trapped in the field. On account of asymmetries in the field, the particles additionally float around the earth, electrons towards the east. Accordingly, they structure a shell around the earth comparable fit as a fiddle to the surface shaped by a field line pivoted around the attractive dipole pivot." 

The United States Defense Threat Reduction Agency issued a report that had been composed in backing of the United States Commission to Assess the Threat to the United States from Electromagnetic Pulse Attack. The report, qualified "Inadvertent blow-back for Satellites from an EMP Attack," talks about in extraordinary subtle element the authentic occasions that brought on simulated radiation cinchs and their consequences for some satellites that were then in circle. The same report likewise ventures the impacts of one or more present-day high height atomic blasts upon the arrangement of manufactured radiation sashs and the likely coming about consequences for satellites that are right now in circle.

Thursday, 14 February 2013

Van Allen radiation belt

The NASA Van Allen Probes mission will go further and gain scientific understanding (to the point of predictability) of how populations of relativistic electrons and ions in space form or change in response to changes in solar activity and the solar wind. NASA Institute for Advanced Concepts–funded studies have proposed magnetic scoops to collect antimatter that occurs naturally in the Van Allen belts of Earth, although it is estimated only about 10 micrograms of antiprotons exist in the entire belt.

The Van Allen Probes mission was successfully launched on August 30, 2012.[5] The primary mission is scheduled to last 2 years, with expendables expected to last for 4 years. NASA's Goddard Space Flight Center manages the overall Living with a Star program of which Van Allen Probes is a project, along with Solar Dynamics Observatory (SDO). The Applied Physics Laboratory is responsible for the overall implementation and instrument management for the Van Allen Probes.

Van Allen radiation belts do exist on other planets in the solar system, whenever a planet or moon has a magnetic field that is powerful enough to sustain a radiation belt. However, many of these radiation belts have been poorly mapped. The Voyager Program (namely Voyager 2) only nominally confirmed the existence of similar belts on Uranus and Neptune.

Friday, 10 August 2012

Van Allen radiation belt

The Van Allen radiation belt is a torus of energetic charged particles (plasma) around Earth, which is held in place by Earth's magnetic field. It is thought that most of the particles that form the belts come from solar wind, and other particles by cosmic rays.

It is named after its discoverer, James Van Allen, and is located in the inner region of the Earth's magnetosphere. It is split into two distinct belts, with energetic electrons forming the outer belt and a combination of protons and electrons forming the inner belts. In addition, the radiation belts contain lesser amounts of other nuclei, such as alpha particles. The belts pose a hazard to satellites, which must protect their sensitive components with adequate shielding if their orbit spends significant time in the radiation belts.

Tuesday, 16 August 2011

Flame-colored Tanager

The Flame-colored Tanager, Piranga bidentata, formerly known as the Stripe-backed Tanager, is a medium-sized American songbird. Formerly placed in the tanager family (Thraupidae), it and other members of its genus are now classified in the cardinal family (Cardinalidae).

The species's plumage and vocalizations are similar to other members of the cardinal family. A tropical passerine bird, the Flame-colored Tanager is found in the mountains of Mexico, and throughout Central America to northern Panama; it is occasionally seen in the United States in the mountains in the southeast corner of Arizona, the southwest of New Mexico and Sonora (the Madrean sky islands of the northern portion of the western Mexican mountain range, Sierra Madre Occidental), and also the southwest corner of Texas.