wave speed a bomb and blact speed
// point on siin, uurida mis vahenditega, milliseid maal kiirusena mõõdetavaid lained või võnkeid nad on mõõtnud. Teada saada kellaajad ja kohad
// kirjutada selleks neile org tuleb, uurida vene a pommi ajastuse mootmist ja metreoriidi oma.
// org nimed siia koos kontaktidega
// kirjad mis kellele kirjutatud, vastused, oleks ka hea siia lingitud eraldi lehele panna
// kui need kiirused paika eipea, siis jällegi väga huvitav
// otsida üles sellle aja ajalehed ja võrrelda aegu, võrrelda vahemaa ja ajaga (punkt 23)
// võrrelda linnade ja mõõtmispunktide vahel reporteeritud aegasi
The meteor that exploded over Chelyabinsk, Russia on February 15, 2013 was so powerful that it sent out ultra-low frequency soundwaves that traveled around the world at least twice.
The meteor was estimated to be 17 meters (56 feet) in diameter and it weighed about 10,000 metric tons. It entered Earth’s atmosphere and approached Russia traveling at speeds near 20 kilometers per second (45,000 miles per hour). The meteor eventually exploded 19 to 24 kilometers (12 to 15 miles) above Earth’s surface. The shockwave from the explosion shattered windows and damaged buildings in nearby cities.
On 15 February 2013, a large Earth-impacting fireball disintegrated over the Ural Mountains. This extraordinary event is, together with the 1908 Tunguska fireball, among the most energetic events ever instrumentally recorded. It generated infrasound returns, after circling the globe, at distances up to ~85,000 km, and was detected at 20 infrasonic stations of the global International Monitoring System (IMS). For the first time since the establishment of the IMS infrasound network, multiple arrivals involving waves that traveled twice round the globe have been clearly identified. A preliminary estimate of the explosive energy using empirical period-yield scaling relations gives a value of 460 kt of TNT equivalent. In the context of the future verification of the Comprehensive Nuclear-Test-Ban Treaty, this event provides a prominent milestone for studying in detail infrasound propagation around the globe for almost 3 days as well as for calibrating the performance of the IMS network.
The approximate effective diameter of the asteroid when it penetrated the atmosphere was estimated to be 17 m and its mass about 10,000 t. Traveling northwest over Russia at a velocity of about 20 km/s
This fireball is the most energetic event reported since 1908, when a meteor broke up over Siberia's Tunguska River. It is also the largest event ever registered by the CTBTO network [Schiermeier, 2013; Showstack, 2013]. The 8 October 2009 meteor that exploded over Indonesia is the most recent similar event detected by 17 IMS stations with an explosive energy estimated at about 50 kt of TNT equivalent
The International Data Centre (IDC) of the CTBTO in Vienna processes automatically and in near real time continuous recordings from the globally deployed IMS infrasound stations. The IDC automatic system is designed to detect explosion-like signals. Station detections are associated to form events. The system can associate signal detections at distances up to 6700 km from the source location. The Russian fireball was automatically detected by the IDC automatic system. The reviewed analysis carried out in the hours following the event provided an extended list of infrasound signals associated with the meteor as well as a refined source location.
At most stations, substantial energy is found at periods larger than 20 s, which is consistent with high explosive energy. Of specific interest are arrivals involving waves that traveled along the minor and major great circle arcs (referred to as Ig1 and Ig2, respectively). For example, arrival Ig1 is observed at IS27 in Antarctica after a propagation over a distance of 14,948 km, while arrival Ig2 that traveled over a distance of 25,127 km is detected about 9 h later in the antipodal direction.
//siin kiiruseks 2 791.89 Kilometers per hour (km/h)
// sound: 1234.8 kilometers per hour
// Seismic wave, velocity tends to increase with depth and ranges from approximately 2 to 8 km/s in the Earth's crust, up to 13 km/s in the deep mantle. (13 km/s 46 800.0 Kilometers per hour , 2 km/s on 7 200.0 (km/h)
// Typical values for P-wave velocity in earthquakes are in the range 5 to 8 km/s. The precise speed varies according to the region of the Earth's interior, from less than 6 km/s in the Earth's crust to 13 km/s through the core
// Infrasonic waves travel with the sound speed which is 340 m/s for air of 20°C.
//Gamma rays, gamma radiation, travel faster than visible light. 2. All electromagnetic waves travel at the same speed in a vacuum. https://chemistry.stackexchange.com/questions/20157/do-radio-waves-or-gamma-radiation-have-a-faster-speed
//To produce a shock wave, an object in a given medium (such as air or water) must travel faster than the local speed of sound. In the case of an aircraft travelling at high subsonic speed, regions of air around the aircraft may be travelling at exactly the speed of sound, so that the sound waves leaving the aircraft pile up on one another, similar to a traffic jam on a motorway. When a shock wave forms, the local air pressure increases and then spreads out sideways. Because of this amplification effect, a shock wave can be very intense, more like an explosion when heard at a distance (not coincidentally, since explosions create shock waves) https://en.wikipedia.org/wiki/Shock_wave
Additional arrivals, Ig3 and Ig5, which circled once and twice round the globe are also clearly observed up to a maximum distance of 86,663 km. Overall, 14 propagation paths are identified as Ig2, Ig3, and Ig5. Such arrivals have not been observed since the last major eruption of Mount Saint
http://onlinelibrary.wiley.com/doi/10.1002/grl.50619/abstract / moned extra lingid, lood all
(muidugi "25,127 km is detected about 9 h " on paar korda kiirem kui helikiirus vist)