The helium abundance varies and is usually well below the normal solar abundance. The wind is mostly hydrogen, with a small percentage of helium by number, and smaller percentages of heavier elements. Those measurements established the theoretical prediction from the hydrodynamics of the solar corona that the expansion of the corona produces an ongoing supersonic wind blowing outward through the solar system.
SOLAR WIND RAM PRESSURE VERIFICATION
The first unambiguous verification of the existence of the solar wind was made from the Venus Mariner, or Mariner II, in 1962. Instruments carried on spacecraft give direct measures of the speed, density, temperature, and atomic composition of the solar wind.
The region dominated by the solar wind is called the heliosphere. The solar wind spreads out as it races off into space, eventually being halted at distances of the order of 10 2 AU by the feeble pressure of the interstellar wind and magnetic field. But even during a month of inactivity at the Sun, the geomagnetic activity never ceases, and there is always an aurora to be seen on any cloudless night at high latitude, implying a continuing wind. Were it not for the wind, that part of the field should quiet down between outbursts from solar flares. Another indication of the solar wind is the ongoing rattling of the magnetic field of Earth, particularly at high geomagnetic latitudes, from where the lines of force extend far out into space. This fact was one of the principal clues leading to recognition of the wind as a simple hydrodynamic phenomenon. The solar wind blows the gaseous tails of comets into the antisolar direction, regardless of the existence or absence of flares or the general level of magnetic activity of the Sun. The solar wind sweeps out through the solar system, ruffling the magnetic fields of the planets and sweeping back the interstellar gas and magnetic field. The million degree outer atmosphere of the Sun (the corona) continually expands to produce the supersonic solar wind. 8 Interaction with the interstellar wind.4 Heat input and the origin of coronal expansion.The press release noted that revolutionaries “are not afraid to break boundaries and change the game. “This is an exciting day for the George Washington University Revolutionaries,” University President Mark Wrighton said in a statement, adding that the moniker “broadly reflects our community - and our distinguished and distinguishable GW spirit.” NBC’s Chuck Todd, an alumnus of the school, announced that “Revolutionaries” would be replacing the “Colonials” in a video posted by the university. The school’s trustees ultimately approved the new moniker among four finalists proposed by a committee of students, faculty, staff and alumni. Since making the decision to replace the school’s Colonials nickname last year, University officials said they received 47,000 points of feedback and 8,000 moniker suggestions, according to a press release. The new nickname, announced Wednesday, will take effect starting in the 2023-2024 academic year. ( The Hill) – George Washington University has selected “Revolutionaries” as its new moniker, after the school decided to scrap its former team nickname - Colonials - under growing student pressure.
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