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2001: A Total Lunar Eclipse
| Title |
2001: A Total Lunar Eclipse |
| Explanation |
The first and only total lunar eclipse for the year 2001 [ http://sunearth.gsfc.nasa.gov/eclipse/OH/OH2001.html ] occured on the evening of January 9/10 as the full Moon glided through Earth's shadow. Unlike [ http://antwrp.gsfc.nasa.gov/apod/ap970827.html ] a total solar eclipse, a total lunar eclipse is visible for anyone on the night side [ http://antwrp.gsfc.nasa.gov/apod/ap001127.html ] of the planet during the event. The night side for this geocentric celestial event [ http://antwrp.gsfc.nasa.gov/apod/ap010104.html ] included Europe, Asia, and Africa where the Moon [ http://www.lunaroutreach.org/ ] could be seen immersed in the umbra or dark portion of Earth's shadow for about 62 minutes as it passed just north [ http://sunearth.gsfc.nasa.gov/eclipse/extra/TLE010109/ TLE2001Jan09-GMT.GIF ] of the shadow's center. This dramatic telescopic photo of [ http://www.MrEclipse.com/MrEclipse.html ] the eclipsed Moon was made near Ankara, Turkey close to the time of midpoint of the total phase. The fact that the northern (top) portion of the eclipsed Moon is clearly brighter, even near mid-totality, demonstrates that Earth's shadow is not uniformly dark. |
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Venus' Evening Loop
| Title |
Venus' Evening Loop |
| Explanation |
From September 2000 through March 2001, astronomer Tunc Tezel patiently photographed the planet Venus on 25 different dates as it wandered [ http://zebu.uoregon.edu/~js/ast221/lectures/ lec06.html ] through the evening twilight. The pictures were taken from the same spot on the campus of the Middle East Technical University near Ankara, Turkey, and timed so that for each photo the Sun was [ http://aa.usno.navy.mil/data/docs/RS_OneYear.html ] 7 degrees below the horizon. Carefully registering and combining the pictures, he produced this composite image -- a stunning demonstration of Venus' grand [ http://stoner.eps.mcgill.ca/~bud/craters/ FaceOfVenus.html ] looping sky motion [ http://sunra.colorado.edu/david/ch1.html ] during its recent stint as planet Earth's evening star [ http://www.library.utoronto.ca/utel/rp/poems/ longfe10.html ]. As indicated, the first picture, taken September 28, 2000, finds Venus [ http://www.windows.ucar.edu/cgi-bin/tour_def/venus/ morning_star.html ] close to the western horizon [ http://antwrp.gsfc.nasa.gov/apod/ap990619.html ] and drifting south (left) with the passing days. By December however, Venus [ http://nssdc.gsfc.nasa.gov/planetary/planets/ venuspage.html ] was climbing well above the horizon after sunset and in January 2001 it reached its maximum apparent distance (elongation [ http://astrosun.tn.cornell.edu/courses/astro201/ planet_view.htm ]) from the Sun. March found Venus [ http://antwrp.gsfc.nasa.gov/apod/ap010308.html ] falling from the evening sky while moving rapidly north, finally appearing (far right) as a faint dot against the sunset glow on March 24. This month, Venus rises before dawn as the brilliant morning star [ http://stardate.utexas.edu/resources/ faqs/049.html ]. |
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Mysterious Streaks Over Turk
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| Title |
Mysterious Streaks Over Turkey |
| Explanation |
What are they? Five streaks near the bottom of the above image taken near Ankara [ http://en.wikipedia.org/wiki/Ankara ], Turkey [ http://en.wikipedia.org/wiki/Turkey ] on Sunday would be identified at first glance as meteors from the Perseids meteor shower [ http://science.nasa.gov/headlines/y2007/11jul_greatperseids.htm ] peaking just that night. Unexpectedly, however, these streaks do not point back to the Perseids radiant [ http://antwrp.gsfc.nasa.gov/apod/ap070812.html ] in Perseus [ http://chandra.harvard.edu/photo/constellations/perseus.html ]. Their origin is therefore somewhat unclear. The above image was captured over the time span of 40 minutes. Other visible celestial icons include the constellation Orion [ http://antwrp.gsfc.nasa.gov/apod/ap070203.html ] and the Pleiades star cluster [ http://antwrp.gsfc.nasa.gov/apod/ap060109.html ]. One hypothesis is that the streaks [ http://antwrp.gsfc.nasa.gov/apod/ap061023.html ] are part of a microburst from a much less active meteor shower known as the Alpha Ursae Majorids [ http://meteorshowersonline.com/showers/alpha_ursa_majorids.html ]. Another possibility is that they are parts of a satellite [ http://www.reentrynews.com/2007023b.html ] that broke up as it re-entered [ http://antwrp.gsfc.nasa.gov/apod/ap000603.html ] the Earth's atmosphere. A discussion of these possibilities can be found here [ http://bb.nightskylive.net/asterisk/viewtopic.php?p=87509 ]. This year's Perseids meteor shower [ http://www.imo.net/live/perseids2007/ ] was a good one, as it was particularly active and corresponded with the dark skies that come with a new moon [ http://antwrp.gsfc.nasa.gov/apod/ap050513.html ]. |
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Earthquakes Strike Turkey, I
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nasa, nasaimageofthedaygalle
…
Two of the world's most eart
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earthquakes_dtam
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2000 |
| creator |
NASA -- Images provided by Jacob Yates, NASA GSFC Laboratory for Terrestrial Physics. |
| identifier |
earthquakes_dtam |
|
Istanbul, Turkey
PIA02665
Sol (our sun)
ASTER
| Title |
Istanbul, Turkey |
| Original Caption Released with Image |
This June 16, 2000 image of Istanbul, Turkey show a full 60 by 60 km ASTER scene in the visible and infrared channels. Vegetation appears red, and urban areas blue-green. Bustling Istanbul, with its magnificent historical heritage, has spanned the divide between Europe and Asia for more than 2,500 years. Originally called Byzantium, the city was founded in the 7th century BC on the Golden Horn, an arm of the narrow Bosporus (also spelled Bosphorus) Strait, which connects the Sea of Marmara to the south, with the Black Sea to the north. Constantine I made it his capital of the Eastern Roman Empire in AD 330. As Constantinople, the strategically located city arose as the preeminent cultural, religious, and political center of the Western world. It reached the height of its wealth and glory in the early 5th century. After centuries of decline, the city entered another period of tremendous growth and prosperity when, as Istanbul, it became the capital of the Turkish Ottoman Empire in 1457. Although Turkey moved its capital to Ankara in 1923, Istanbul remains the nation's largest city with a population of over 8 million, its commercial center, and a major port. Two bridges spanning the Bosporus, and ships in the busy channel can be seen on the enlargement. On the image, the water areas have been replaced with a thermal image: colder waters are displayed in dark blue, warmer areas in light blue. Note the dark lines showing boat wakes, and the cold water entering the Sea of Marmara from deeper waters of the Bosporus. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, Calif., is the U.S. Science team leader, Moshe Pniel of JPL is the project manager. ASTER is the only high resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats, monitoring potentially active volcanoes, identifying crop stress, determining cloud morphology and physical properties, wetlands Evaluation, thermal pollution monitoring, coral reef degradation, surface temperature mapping of soils and geology, and measuring surface heat balance. |
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