4. 115 NAVY SPACE 115.2 a. The Sun. [ref. b] The sun has the biggest effect on the space environment. Fueled by nuclear fusion, the sun combines or “fuses” 600 million tons of hydrogen each second. Two by-products of the fusion process that impact space systems are: Electromagnetic Radiation and Electrically Charged Particles.
5. 115 NAVY SPACE 115.2 b. Solar Wind. [ref. b] Solar wind is electrically charged particles that stream continuously from the Sun. This excited state of atmospheric molecules degrades radar performance in the auroral zones, including ballistic missile warning radar. It can also adversely affect satellites at altitudes to 600 miles, to include polar orbiting satellites.
6. 115 NAVY SPACE 115.2 c. Solar Cycle. [ref. b] Solar activity is cyclic in nature, following an 11-year cycle which is called the Solar Cycle. Generally there is a 4-year rise to a solar maximum, followed by a gradual 7-year decline to solar minimum.
7. 115 NAVY SPACE Largest Solar Flare on record. Off the chart coronal mass ejection.
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9. 115 NAVY SPACE VAN ALLEN RADIATION BELTS ATMOSPHERIC DRAG
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12. 115 NAVY SPACE POES 115.3 (CONT.) Polar Orbiting Environmental Satellites (POES) are two polar-orbiting satellites constantly circling the Earth in an almost north-south orbit, passing close to both poles.
The Rapid Service/Prediction Center of the International Earth Rotation and Reference Systems Service (IERS), located at the U.S. Naval Observatory (USNO), monitors the Earth's orientation and disseminates this information to many organizations on a continuous basis. Geodetic Very Long Baseline Interferometry (VLBI) is a space-based technique which allows for accurate measurement of the Earth and its orientation in inertial space. An inertial frame is defined by compact radio sources, billions of light years from Earth, called quasars. The Earth’s orientation in this inertial reference frame is measured. The quasars are observed with a global network of radio telescopes. Telescopes in the network simultaneously record signals from quasars together with signals from local atomic clocks onto hard disks. At the correlator, data are played back to determine differential time delays. From these differences in arrival times of signals at the various telescopes, the baselines between the telescopes can be determined with an accuracy of a few millimetres. In addition, VLBI data allows us determine the CRF and TRF and to measure Earth orientation parameters (EOP) as well as tropospheric parameters.