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Space Industry
Space industry refers to economic activities related to manufacturing components that go into outer space (Earth's orbit or beyond), delivering them to those regions, and related services. Owing to the prominence of satellite-related activities, some sources use the term satellite industry interchangeably with the term space industry. The term space business has also been used. A narrow definition of the space industry typically encompasses only hardware providers (primarily those that manufacture launch vehicles and satellites). This definition does not exclude certain activities, such as space tourism. Therefore, more broadly, the space industry can be described as the activities of the companies and organizations involved in the space economy, and providing goods and services related to space. The space economy has been defined as "all public and private actors involved in developing and providing space-enabled products and services. It comprises a long value-added chaini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Starlink Mission (47926144123)
Starlink is a satellite internet constellation operated by Starlink Services, LLC, an international telecommunications provider that is a wholly owned subsidiary of American aerospace company SpaceX, providing coverage to around 130 countries and territories. Timestamp 12:00. It also aims to provide global mobile broadband. Starlink has been instrumental to SpaceX's growth. SpaceX began launching Starlink satellites in 2019. , the constellation consists of over 7,600 mass-produced small satellites in low Earth orbit (LEO) that communicate with designated ground transceivers, and Starlink comprises 65% of all active satellites. Nearly 12,000 satellites are planned, with a possible later extension to 34,400. SpaceX announced reaching over 1 million subscribers in December 2022 and 4 million subscribers in September 2024. The SpaceX satellite development facility in Redmond, Washington, houses Starlink research, development, manufacturing, and orbit control facilitie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World War II
World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the world's countries participated, with many nations mobilising all resources in pursuit of total war. Tanks in World War II, Tanks and Air warfare of World War II, aircraft played major roles, enabling the strategic bombing of cities and delivery of the Atomic bombings of Hiroshima and Nagasaki, first and only nuclear weapons ever used in war. World War II is the List of wars by death toll, deadliest conflict in history, causing World War II casualties, the death of 70 to 85 million people, more than half of whom were civilians. Millions died in genocides, including the Holocaust, and by massacres, starvation, and disease. After the Allied victory, Allied-occupied Germany, Germany, Allied-occupied Austria, Austria, Occupation of Japan, Japan, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorine
Chlorine is a chemical element; it has Symbol (chemistry), symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate between them. Chlorine is a yellow-green gas at room temperature. It is an extremely reactive element and a strong oxidizing agent, oxidising agent: among the elements, it has the highest electron affinity and the third-highest electronegativity on the revised Electronegativity#Pauling electronegativity, Pauling scale, behind only oxygen and fluorine. Chlorine played an important role in the experiments conducted by medieval Alchemy, alchemists, which commonly involved the heating of chloride Salt (chemistry), salts like ammonium chloride (sal ammoniac) and sodium chloride (common salt), producing various chemical substances containing chlorine such as hydrogen chloride, mercury(II) chloride (corrosive sublimate), and . However, the nature of fre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ozone Layer
The ozone layer or ozone shield is a region of Earth's stratosphere that absorption (electromagnetic radiation), absorbs most of the Sun's ultraviolet radiation. It contains a high concentration of ozone (O3) in relation to other parts of the atmosphere, although still small in relation to other gases in the stratosphere. The ozone layer peaks at 8 to 15 parts per million of ozone, while the average ozone concentration in Earth's atmosphere as a whole is about 0.3 parts per million. The ozone layer is mainly found in the lower portion of the stratosphere, from approximately above Earth, although its thickness varies seasonally and geographically. The ozone layer was discovered in 1913 by French physicists Charles Fabry and Henri Buisson. Measurements of the sun showed that the radiation sent out from its surface and reaching the ground on Earth is usually consistent with the spectrum of a black body with a temperature in the range of , except that there was no radiation below a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2009 Satellite Collision
On February 10, 2009, two communications satellites—the active commercial Iridium 33 and the derelict Russian military Kosmos 2251—accidentally collided at a speed of and an altitude of above the Taymyr Peninsula in Siberia. It was the first time a hypervelocity collision occurred between two satellites; previous incidents had involved a satellite and a piece of space debris. Spacecraft Kosmos 2251 was a Russian Strela military communications satellite owned by the Russian Space Forces. Kosmos 2251 was launched on a Russian Cosmos-3M carrier rocket on June 16, 1993. This satellite had been deactivated prior to the collision, and remained in orbit as space debris. The other spacecraft, Iridium33, was a U.S.-built commercial satellite that was part of the Iridium constellation for satellite phones. It was launched on September 14, 1997, atop a Russian Proton rocket. Conjunction and collision Events where two satellites approach within several kilometers of each othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kessler Syndrome
The Kessler syndrome, also known as the Kessler effect, collisional cascading, or ablation cascade, is a scenario proposed by NASA scientists Donald J. Kessler and Burton G. Cour-Palais in 1978. It describes a situation in which the density of objects in low Earth orbit (LEO) becomes so high due to space pollution that collisions between these objects cascade, exponentially increasing the amount of space debris over time. This proliferation of debris poses significant risks to satellites, space missions, and the International Space Station, potentially rendering certain orbital regions unusable and threatening the sustainability of space activities for many generations. In 2009, Kessler wrote that modeling results indicated the debris environment had already become unstable, meaning that efforts to achieve a growth-free small debris environment by eliminating past debris sources would likely fail because fragments from future collisions would accumulate faster than atmospheric d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Debris
Space debris (also known as space junk, space pollution, space waste, space trash, space garbage, or cosmic debris) are defunct human-made objects in spaceprincipally in Earth orbitwhich no longer serve a useful function. These include derelict spacecraft (nonfunctional spacecraft and abandoned launch vehicle stages), mission-related debris, and particularly numerous in-Earth orbit, fragmentation debris from the breakup of derelict rocket bodies and spacecraft. In addition to derelict human-made objects left in orbit, space debris includes fragments from disintegration, erosion, or collisions; solidified liquids expelled from spacecraft; unburned particles from solid rocket motors; and even paint flecks. Space debris represents a risk to spacecraft. Space debris is typically a negative externality. It creates an external cost on others from the initial action to launch or use a spacecraft in near-Earth orbit, a cost that is typically not taken into account nor fully accoun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Remote Sensing
Remote sensing is the acquisition of information about an physical object, object or phenomenon without making physical contact with the object, in contrast to in situ or on-site observation. The term is applied especially to acquiring information about Earth and other planets. Remote sensing is used in numerous fields, including geophysics, geography, land surveying and most Earth science disciplines (e.g. exploration geophysics, hydrology, ecology, meteorology, oceanography, glaciology, geology). It also has military, intelligence, commercial, economic, planning, and humanitarian applications, among others. In current usage, the term ''remote sensing'' generally refers to the use of satellite- or airborne-based sensor technologies to detect and classify objects on Earth. It includes the surface and the atmosphere and oceans, based on wave propagation, propagated signals (e.g. electromagnetic radiation). It may be split into "active" remote sensing (when a signal is emitted b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ka-band
The Ka band (pronounced as either "kay-ay band" or "ka band") is a portion of the microwave part of the electromagnetic spectrum. The designation "Ka-band" is from Kurz-above, which stems from the German word ''kurz,'' meaning "short". There is no standard definition of Ka-band. IEEE Standard letter designations for Radar Bands define the nominal frequency range for Ka band in the range 27–40 gigahertz (GHz) in Tables 1 and 2 of IEEE Standard 521 i.e. wavelengths from slightly over one centimeter down to 7.5 millimeters. The ITU however approves Ka-band satellite networks in the 17.3-31 GHz frequency range, with most Ka-band satellite networks having uplinks in the 27.5–31 GHz and downlinks in the 17.7–21.2 GHz range. The band is called Ka, short for "K-above" because it is the upper part of the original (now obsolete) NATO K band, which was split into three bands because of the presence of the atmospheric water vapor resonance peak at 22.24 G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2008 Financial Crisis
The 2008 financial crisis, also known as the global financial crisis (GFC), was a major worldwide financial crisis centered in the United States. The causes of the 2008 crisis included excessive speculation on housing values by both homeowners and financial institutions that led to the 2000s United States housing bubble, exacerbated by predatory lending for subprime mortgages and deficiencies in regulation. Cash out refinancings had fueled an increase in consumption that could no longer be sustained when home prices declined. The first phase of the crisis was the subprime mortgage crisis, which began in early 2007, as mortgage-backed securities (MBS) tied to U.S. real estate, and a vast web of Derivative (finance), derivatives linked to those MBS, collapsed in value. A liquidity crisis spread to global institutions by mid-2007 and climaxed with the bankruptcy of Lehman Brothers in September 2008, which triggered a stock market crash and bank runs in several countries. The crisis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mobile-satellite Service
Mobile-satellite service (MSS, or mobile-satellite radiocommunication service) is – according to Article 1.25 of the International Telecommunication Union's Radio Regulations – "A radiocommunication service * between mobile earth stations and one or more space stations, or between space stations used by this service; or * between mobile earth stations by means of one or more space stations. This service may also include feeder links necessary for its operation." Details Most commercial voice and some data mobile satellite services are provided by systems operating in the L-band by Iridium, Inmarsat, Globalstar and Thuraya. The L-band spectrum allocated for MSS is between 1.5 and 2.5 GHz, with the upper portion often referred to as the S-band. Constellations of low earth orbiting (LEO) satellites are used by Iridium (66 satellites) and Globalstar (48 satellites). Inmarsat and Thuraya currently use 4 (i4) and 2 geostationary satellites respectively, their L-band services ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fixed Service Satellite
Fixed-satellite service (FSS, or fixed-satellite radiocommunication service) is – according to ''article 1.21'' of the International Telecommunication Union, International Telecommunication Union's (ITU) ITU Radio Regulations, Radio Regulations (RR) – defined as ''A radiocommunication service between earth stations at given positions, when one or more satellites are used; the given position may be a specified fixed point or any fixed point within specified areas; in some cases this service includes satellite-to-satellite links, which may also be operated in the inter-satellite service; the fixed-satellite service may also include feeder links for other space radiocommunication services.'' Classification This ''radiocommunication service'' is classified in accordance with ''ITU Radio Regulations'' (article 1) as follows: Fixed service (article 1.20) * Fixed-satellite service (article 1.21) *Inter-satellite service (article 1.22) *Earth exploration-satellite service (article 1.5 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
