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| | [sci.astro] Time (Astronomy Frequently Asked Questions) (3/9) |
 | | The 24h notation is the official international standard time notation (ISO 8601) and displayed by almost all digital clocks outside the U.S.A. The 24h notation is also recommended by the U.S. Naval Observatory in Washington, which defines official time in the U.S.) MEAN SOLAR TIME: True Solar Time isn't a uniform time. | | | SIDEREAL TIME: Closely connected with the Mean Solar Time is the Sidereal Time, which is defined as the RA (Right Ascension) of the Local Meridian: when the Vernal Point passes the meridian it is 00:00 Sidereal Time. | | | The Sidereal Time at a particular place and location is the same as the local Mean Solar Time, plus 12 hours, plus the Right Ascension of the Mean Sun (which is the same as the Mean Longitude of the true sun). |
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http://www.faqs.org/faqs/astronomy/faq/part3
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| | fUSION Anomaly. Time |
| | The length of the day according to solar time is not the same throughout the year, however, because the apparent motion of the sun varies throughout the year. | | | A system by which such intervals are measured or such numbers are reckoned: solar time. | | | Neither mean solar time nor mean sidereal time is precisely accurate, because the motion of the earth on its axis is not regular. |
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http://fusionanomaly.net/time.html
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| | Z-Time - by Harold F. Maybeck |
| | It had been well understood by navigators that there being 24 hours in a solar day (23h 56m 4.091s in a sidereal day), and since there are 360° of longitude around the earth, that each 15° of longitude constituted another 1 hour time-zone. | | | This notation, "Z", is appended to times on most navigational, meteorological, and astronomical charts today to indicate that the time of the chart is in "Greenwich Mean Time". | | | In most handwritten and non-technical writings, the time is usually just appended with the notation "Z". |
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http://www.maybeck.com/ztime
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| | Time scale |
| | Solar time is based on the solar day, which is the period of time between one solar noon and the next. | | | Universal Time (UT) is a time scale based the mean solar day, defined to be as uniform as possible despite variations in the rotation of the Earth. | | | The internationally recognized time interval is the second. |
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http://www.brainyencyclopedia.com/encyclopedia/t/ti/time_scale.html
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| | [sci.astro] Time (Astronomy Frequently Asked Questions) (3/9) |
| | The 24h notation is the official international standard time notation (ISO 8601) and displayed by almost all digital clocks outside the U.S.A. The 24h notation is also recommended by the U.S. Naval Observatory in Washington, which defines official time in the U.S.) MEAN SOLAR TIME: True Solar Time isn't a uniform time. | | | SIDEREAL TIME: Closely connected with the Mean Solar Time is the Sidereal Time, which is defined as the RA (Right Ascension) of the Local Meridian: when the Vernal Point passes the meridian it is 00:00 Sidereal Time. | | | The Sidereal Time at a particular place and location is the same as the local Mean Solar Time, plus 12 hours, plus the Right Ascension of the Mean Sun (which is the same as the Mean Longitude of the true sun). |
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http://www.faqs.org/faqs/astronomy/faq/part3
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| | fUSION Anomaly. Time |
| | The length of the day according to solar time is not the same throughout the year, however, because the apparent motion of the sun varies throughout the year. | | | A system by which such intervals are measured or such numbers are reckoned: solar time. | | | Neither mean solar time nor mean sidereal time is precisely accurate, because the motion of the earth on its axis is not regular. |
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http://fusionanomaly.net/time.html
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| | daylight saving time - Columbia Encyclopedia article about daylight saving time |
| | Civil time may be formally defined as mean solar time plus 12 hr; the civil day begins at midnight, while the mean solar day begins at noon. | | | The length of a solar day varies during the course of a year, so for purposes of time measurement an average, or mean, solar day is used (see solar time), equal to exactly 24 hr. | | | In 1987 federal legislation fixed the period of daylight saving time in the United States as the first Sunday (previously the last Sunday) in April to the last Sunday in October. |
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http://columbia.thefreedictionary.com/daylight+saving+time
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| | The truth on Summer time |
| | That it indicates 5 at summer time or 7 solar time changes nothing. | | | 59% are for solar time, but german time has still supporters (33%). | | | The problem of large countries which cover several time zones was well managed in the USA, where the legal time zones were set as close as possible of the true solar time zones, accounting with the state limits. |
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http://www.shedrupling.org/activist/heure/heure.php?lang=en
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| | Sunbathing at Solar Maximum |
| | There are more sunspots, solar flares and UV rays from the Sun than at any time since 1989. | | | Extreme ultraviolet photons from the Sun are at least 10 times more energetic than UV-A and UV-B and they vary 100 times more [between solar minimum and solar maximum]. | | | In 1996, near solar minimum, the extreme ultraviolet Sun was nearly featureless. |
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http://science.nasa.gov/headlines/y2000/ast05sep_1.htm?list
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| | Eyes on the Sky, Feet on the Ground: Chapter Three |
| | As mentioned earlier, this lunar measuring was not consistent with the solar year; thus it was 11 1/4 days shorter than the 365 1/4 days which comprise a solar year. | | | As a result, governments often keep precise time and provide signals to navigators, astronomers, and anyone else who wants to "listen in". | | | Repeat this measurement and make a chart of this time difference for each week. |
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http://hea-www.harvard.edu/ECT/the_book/Chap3/Chapter3.html
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| | Solar Wind - Reviews |
| | If this is only the second outing from Solar Wind and company, we can expect the jazz world to be refreshed for a long time to come. | | | While many of the tracks on Solar Wind's sophomore CD, Blue Horizon (Solar One), bear warm, sunny titles and are as sparkling and easy to enjoy as a bright summer day on the beach, this is not a lightweight album. | | | Solar Wind's new release won't suffer the fate of many solo albums, played once or twice and then shelved. |
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http://www.solar-wind.com/reviews.html
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| | Astronomical Time Keeping |
| | TCB is the proper time of the barycentre of the solar system. | | | Since the time reading at the Sun's passage through the meridian should be 12 h, though, the true solar time comes out as the hour angle of the anti-sun (which is the fictitious point on the ecliptic opposite to the Sun). | | | With these definitions, Ephemeris Time is equivalent to the time values in Newcomb's tables of the solar position. |
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http://www.maa.mhn.de/Scholar/times.html
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| | [sci.astro] Time (Astronomy Frequently Asked Questions) (3/9) |
| | The 24h notation is the official international standard time notation (ISO 8601) and displayed by almost all digital clocks outside the U.S.A. The 24h notation is also recommended by the U.S. Naval Observatory in Washington, which defines official time in the U.S.) MEAN SOLAR TIME: True Solar Time isn't a uniform time. | | | SIDEREAL TIME: Closely connected with the Mean Solar Time is the Sidereal Time, which is defined as the RA (Right Ascension) of the Local Meridian: when the Vernal Point passes the meridian it is 00:00 Sidereal Time. | | | A shorter and more obvious time notation is the modern 24h notation in which the hours in the day range from 00:00 to 23:59. |
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http://www.faqs.org/faqs/astronomy/faq/part3
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| | NASA - Tuesday/Wednesday Solar Punch |
| | The also-powerful CME, which solar scientists think was accelerated by the eruption of the flare, is headed toward us at 2,000 kilometers per second (1,250 miles per second), nearly five times faster than a normal CME, says Bernhard Fleck, ESA SOHO Project Scientist. | | | SOHO is the SOlar and Heliospheric Observatory satellite, a joint NASA/ESA mission, one instrument with which scientists observed this event. | | | The third most-powerful solar flare ever observed in X-ray wavelengths erupted from Sunspot 486 early October 28, 2003, at approximately 6 a.m. |
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http://www.nasa.gov/vision/universe/solarsystem/10.28Flare.html
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| | Time zone - encyclopedia article about Time zone. |
| | Apparent solar time is based on the apparent solar day, which is the interval between two successive returns of the Sun to the local meridian. | | | Solar time can be measured by a sundial. | | | These were to be vocalized using a phonetic alphabet which included Zulu for GMT, leading sometimes to the use of the term 'Zulu Time'. |
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http://encyclopedia.thefreedictionary.com/Time+zone
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| | Time Scales |
| | There is little dispute that it is far more important for everyone to be able to agree on the value of civil time to within 100 nanoseconds than it is for civil time to have a value that tracks mean solar time to within 100 milliseconds. | | | In the sexagesimal notation used for these subdivisions the time tag 12:00:00 has long been understood to indicate that the sun is nearly overhead. | | | This time scale is an effort to ascertain corrections to the values of TAI based on retrospective studies of the behavior of the clocks which have contributed to TAI. |
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http://www.ucolick.org/%7Esla/leapsecs/timescales.html
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| | Equation of Time · Astrological definition of Equation of Time · Astrology Encyclopedia |
| | The moment the Sun is exactly on the Midheaven of any place is apparent noon at that place; hence an apparent solar day is the interval between two consecutive passages of the Sun across the Midheaven, or the elapsed time from one apparent noon to the next. | | | The difference between mean solar time and apparent solar time. | | | War Time · Watchers of the Heavens · Water-bearer, Waterman · Water Signs · Wave Length · Weak Signs · Whole Signs |
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http://www.astrologyweekly.com/dictionary/equation-of-time.php
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| | AAS Biographical Memoirs - Richard van der Riet Woolley 1906-1986 |
| | The two papers he did rather surprisingly manage to publish during that time were quite properly on solar astronomy because he was directing a still nominally 'solar' observatory. | | | About the same time, another significant excursion in Woolley's scientific concerns was into radio astromony. | | | Although he and D.F. Martyn remained in close touch and Martyn had some collaboration with some of Woolley's colleagues after this one ionospheric interlude Woolley himself switched back to studying, along with some of these colleagues, what goes on at the solar end of the business. |
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http://www.asap.unimelb.edu.au/bsparcs/aasmemoirs/woolley.htm
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| | Leap Seconds |
| | Modern studies have indicated that the epoch at which the mean solar day was exactly 86,400 SI seconds was approximately 1820. | | | That is, the length of the mean solar day is at present about 86,400.002 seconds instead of exactly 86,400 seconds. | | | Definitions of these time scales are given in Systems of Time. |
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http://tycho.usno.navy.mil/leapsec.html
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| | europe |
| | Previously, local mean solar time was used in different parts # of Iceland, the almanak had been based on Reykjavik mean solar time which # was 1 hour and 28 minutes behind GMT. | | | The end of # daylight saving time is performed on the last Sunday of September at 03:00 # (GMT 00:00), turning the hands of the clock 1 hour backward. | | | # Specified a one hour offset from GMT (DMT in Ireland), dates of # Sunday 21 May and Sunday 1 October and times of 02:00 (GMT/DMT). |
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http://www.cis.temple.edu/~ingargio/software/glibc-2.1.2/timezone/europe
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| | Telling Time by the Stars - Sidereal Time |
| | Estimate the sidereal time at 3:00 pm solar time on November 29 of the same year. | | | Let the vernal equinox occur at noon solar time on March 21 of a certain year. | | | (i.e., a sidereal clock at noon solar time on November 29 reads 4 hr 21 min ahead of a solar clock). |
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http://www.grc.nasa.gov/WWW/K-12/Numbers/Math/Mathematical_Thinking/telling_time_by_the_stars.htm
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| | The Time |
| | Geocentric Coordinate Time, or TCG, is the same as Barycentric Coordinate Time, except that it uses the Earth's center, rather than the barycenter of the solar system (and an “asymptotic” observer is one free from the gravitational field of the Earth rather than that of all the solar system). | | | More precisely, it is the time coordinate of a space-time coordinate system that is centered in space on the barycenter of the solar system, that is nonrotating with respect to distant galaxies, and that tends asymptotically to the proper time of an observer at rest with respect to the coordinate system. | | | The metre is the length of the path traveled by light in vacuum during a time interval of 1/299792458 of a second. |
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http://www.madore.org/~david/misc/time.html
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| | Solar Storms |
| | Long uninterrupted pipelines also can bring solar storms "down to Earth." Magnetic storm currents acting on pipelines are known to enhance the rate of corrosion over time, with potentially catastrophic cumulative effects. | | | Already, we are well on the way to the next solar maximum, expected to peak next year. | | | When the solar wind hits the Earth's magnetic field, electrons and protons inside the field are accelerated into currents that flow along the gossamer-thin magnetic field lines and converge on the polar regions. |
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http://solar.physics.montana.edu/press/WashPost/Horizon/196l-031099-idx.html
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| | Shuttle Columbia Disaster; Wrong Place, Wrong Time! |
| | The solar shock wave hitting the atmosphere at approximately this time would pump energy into the ionosphere, particularly the current sheets which follow the dawn and dusk, the shuttle happened to be passing through from darkness into the dawn at the time of the out-of-family (not consistent with past flights) communication drop outs. | | | The symbol used for points from the trajectory data file is a red dot at 0.96 second time intervals, GPS data dropouts are areas between the track missing the red dots. | | | They said at the end of the research that I had saved them 10-15 years of time with the material I provided them. |
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http://www.superforce.com/shuttle
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| | Scandinavian Indie Digest Vol.3 Issue #28 |
| | This time it is a Solar Lodge contest, and you better answer the simple questions in a hurry at: http://www.lysator.liu.se/~chief/beatcont.html. | | | Unfortunately I will not have the time to make a cover, as promised before, before I send the tape, but I will make one, and post it to the list and put it on the Web-pages so if you want one, just grab it when it is ready and print it out. | | | I can tape any of that stuff for ya....I've got all the original Icelandic vinyl by Tappi, Kukl & Theyr (except for the VERY first Theyr album, "Pagad i Hel"....which is kinda rare (understatement). |
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http://www.lysator.liu.se/~chief/SID/sid-328.html
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| | 1994 Total Solar Eclipse |
| | In a total solar eclipse, the end of the moon's conical shadow (umbra) usually moves rapidly across the earth from west to east. | | | Those inside the shadow will see a total solar eclipse. | | | A total solar eclipse occurs when the moon moves directly between the earth and the sun, and when the moon is close enough to the earth that its apparent diameter is larger than that of the sun. |
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http://www.eclipsechaser.com/eclink/ecjrnl/ecj94p1.htm
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| | : Million Solar Roofs |
| | The Million Solar Roofs Initiative is a unique public-private partnership, aimed at overcoming barriers to market entry for selected solar technologies. | | | Million Solar Roofs (MSR) is helping increase the market for solar energy. | | | Eligible technologies include photovoltaics (PV), solar water heating, transpired solar collectors, solar space heating and cooling and pool heating. |
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http://www.millionsolarroofs.org
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| | Time determination by stars, Sun, and Moon (from calendar) -- Encyclopædia Britannica |
| | Information on this star around which the earth and other planets of the solar system revolve.Includes details of photosphere, chromosphere, corona, and solar winds. | | | Known since prehistoric times, it is the brightest object in the sky after the Sun. | | | More results on "Time determination by stars, Sun, and Moon (from calendar)" when you join. |
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http://www.britannica.com/eb/article-59344
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| | GPS, UTC, and TAI Clocks |
| | The Times of your Life Solar Time, Julian Days, Sidereal Time | | | A brief history of time scales Steve Allen, UCO/Lick Observatory | | | Some basic information about the different time scales by Paul Schlyter |
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http://www.leapsecond.com/java/gpsclock.htm
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