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The Webmaster is only able to use one hand to type. Because of that, a dictation program is frequently used. The program continually scans the dictation and often makes random changes in the text after final (pre-publication) proofreading has been made.
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Comets How do comets effect radio communication? Summary: When solid materials (meteors) enter Earth's atmosphere they heat up to temperatures that ionize columns of air. Hams are able to bounce radio signals falling between 50 and 432 MHz off of some of these ionized columns. This form of propagation is known as meteor scatter. As mentioned some comets seed solid materials in Earth's solar orbital path. Halley's Comet is responsible to two annual meteor showers - Orionids and Eta Aquarids . Amateur radio operators can use meteor showers to enhance propagation on several ham bands. 6 meters is the band of choice for meteor scatter because the reflected radio signals are of longer duration and greater signal strength than at higher frequencies. Details on using meteor scatter for amateur communications can be found on the " Meteor Scatter " page. 19
Oct 2001 :
Orionid Radiant : Above: Observers at mid-northern latitudes can find the radiant of the Orionid meteor shower in the southeastern sky at 3 a.m. local time on October 21st. Click here for a southern hemisphere sky map. _____________________________________________ Looking for Information concerning Sharon Lombardi's cosmic discovery. Original information welcomed. _______________
" SOHO is a unique satellite operating from a permanent vantage point 1.5 million kilometers ahead of the Earth in a halo orbit around the L1 Lagrangian point. SOHO Will observe the Sun continuously for at least two years. Previous satellites functioning as solar observatories were periodically interrupted as Earth `eclipsed' the Sun." NASA Coronagraph images at the SOHO web site are updated every 30 minutes. You get to see the solar images at the same time that the scientists at NASA and the European Space Agency do. Amateurs are in the lead for discovering new comets in real-time. Approximately one new comet a week is discovered using the SOHO images.
If you think you've found something, first review the basic criteria for a discovery before forwarding the details to scientists at the Goddard Space Flight Center. Send your discovery to: doug@sungrazer.nascom.nasa.gov Will I win a prize and have the comet named after me? Well .... By convention, comets discovered in SOHO data are named after the spacecraft rather than the astronomer. Both real-time and archival images are accessible at the SOHO web site _______________ The SOHO Mission SOHO is designed to study the internal structure of the Sun, its extensive outer atmosphere and the origin of the solar wind. Structure of the Sun " Solar Atmosphere "This image of the solar atmosphere
at a temperature of about 100,000 Solar Wind and Corona
The Sun continuously blows off a magnetized plasma known as the solar wind which results from heating." Photo and text NASA Images including the Sun and comets are found on the "Photo Album" page. _______________
Where did all these sungrazing comets come from ? "The origin of these sungrazing comets appear to be fragments of a single giant comet that broke apart near perihelion (closest approach to the Sun) long ago. It is speculated that the parent might have been a bright comet seen by the Greek astronomer Ephorus in 372 BC. Ephorus reported that the comet split in two." " Splits may have occurred again and
again, producing the Kreutz sungrazer family (named after the nineteenth-century
German astronomer who studied them in some detail). The sungrazers share an
elliptical orbit that brings some of the fragments less than 50,000 km from the
Sun." Return to top of Page Home Go to Photo Album page
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