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The International Space Station (ISS) is a large space station assembled and maintained in low Earth orbit by a collaboration of five space agencies and their contractors: NASA (United States), Roscosmos (Russia), JAXA (Japan), ESA (Europe), and CSA (Canada). The ISS is the largest space station ever built. Its primary purpose is to perform ...
Dyson sphere. A hypothetical depiction of a Dyson swarm surrounding a star. Freeman Dyson, the first scientist to explore the concept. A Dyson sphere is a hypothetical megastructure that encompasses a star and captures a large percentage of its solar power output. [1] [2] [3] The concept is a thought experiment that attempts to imagine how a ...
Wireless LAN (WLAN) channels are frequently accessed using IEEE 802.11 protocols. The 802.11 standard provides several radio frequency bands for use in Wi-Fi communications, each divided into a multitude of channels numbered at 5 MHz spacing (except in the 45/60 GHz band, where they are 0.54/1.08/2.16 GHz apart) between the centre frequency of the channel.
Starlink is a satellite internet constellation operated by Starlink Services, LLC, a wholly-owned subsidiary of American aerospace company SpaceX,[3] providing coverage to over 70 countries. It also aims to provide global mobile broadband.[4] SpaceX started launching Starlink satellites in 2019. As of early March 2024, it consists of over ...
In mathematics, a spherical coordinate system is a coordinate system for three-dimensional space where the position of a given point in space is specified by three numbers, ( r, θ, φ ): the radial distance of the radial line r connecting the point to the fixed point of origin (which is located on a fixed polar axis, or zenith direction axis ...
The earliest datable record of an aurora was recorded in the Bamboo Annals, a historical chronicle of the history of ancient China, in 977 or 957 BC. An aurora was described by the Greek explorer Pytheas in the 4th century BC. Seneca wrote about auroras in the first book of his Naturales Quaestiones, classifying them, for instance, as pithaei ('barrel-like'); chasmata ('chasm'); pogoniae ...
Mount Fuji (富士山, Fujisan, Japanese: [ɸɯ (d)ʑisaɴ] ) is an active stratovolcano located on the Japanese island of Honshu, with a summit elevation of 3,776.24 m (12,389 ft 3 in).It is the tallest mountain in Japan, the second-highest volcano located on an island in Asia (after Mount Kerinci on the Indonesian island of Sumatra), and seventh-highest peak of an island on Earth.
