... The Round Earth . ... Aristarchus around 270 BC derived the Moon's distance from the duration of a lunar eclipse (Hipparchus later found an independent method). ... Let R be the radius of that circle and T the time it takes the Moon to go around once, about one month. ... Viewed from Earth, a "new Moon" (occuring between the time a thin crescent is last seen before sunrise and the time one is seen shortly after sunset) happens when the Moon in its apparent motion around the sky overtakes the Sun. ...

... Shadow Cone of a Total Solar Eclipse . ... Credit Copyright: Oliver Staiger ( High Moon ) Explanation: Sometimes, during a total eclipse of the Sun, a strange shadow of darkness can be seen stretching off into the distance. Called a shadow cone, they are visible because the Earth's atmosphere is not completely transparent, scattering sunlight and hence appearing blue during the day. ... Visible above is a shadow cone caught during a total solar eclipse visible last month from South Australia . ...

... The greater the distance, the smaller the parallax. ... That triangle has the same proportions as the much larger triangle ABC, and therefore, if the distance B'C to the thumb is 10 times the distance A'B' between the eyes, the distance AC to the far landmark is also 10 times the distance AB. ... The most distant objects our eyes can see are the stars, and they are very far indeed: light which moves at 300,000 kilometers (186,000 miles) per second, would take years, often many years, to reach them. ...

... 2003 January 6 . Shadow Cone of a Total Solar Eclipse . ... Explanation: Sometimes, during a total eclipse of the Sun, a strange shadow of darkness can be seen stretching off into the distance. Called a shadow cone, they are visible because the Earth's atmosphere is not completely transparent, scattering sunlight and hence appearing blue during the day. ... Visible above is a shadow cone caught during a total solar eclipse visible last month from South Australia . ... About APOD | ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... Lightcurve of HW Vir from images obtained using the Faulkes Telescope South, operated by Las Cumbres Observatory . The blue triangles show the difference between two stars whose brightness is constant. ... This shows the value of the Faulkes Telescopes in the follow-up observations of eclipsing binaries with the aim to detect and characterise additional circumbinary companions. ...

Educator's Guide to Eclipses . ... In a solar eclipse you observe the Sun (using only safe methods, of course). ... In a lunar eclipse you observe the Moon. ... Because of the geometry described below, you can only view a solar eclipse when the Sun is up, and the Moon is nowhere to be seen. ... Eclipses occur when the Sun, Earth and Moon line up. ... In a solar eclipse the Moon passes directly in front of the Sun. ... In a lunar eclipse the Moon moves into Earth's shadow. ...

... On the morning of Thursday, 26 February, amid the Gal pagos Islands, the Sun will fade from view. Not the culmination of ancient prophecy, but none less mystical, Earth's small Moon will be executing a slow slide past the enormous Sun. ... And anyone living in southern North America, Central America, northern South America, or on islands and cruise ships in the Caribbean Sea will, weather permitting, have the opportunity to experience the wonder of a solar eclipse. ...

... Home eclipse_10_08_2014 . ... Lecture Series 2014-2015 . ... AAA Fall Astronomy Class: Astronomy Basics тАУ October-November 2015 . ... This Month's Sky . ... This Month's Sky - 2015 . This Month's Sky - January 2015 . ... Beyond New York City . ... Observing Resources for Amateur Astronomers - Part 1: Beginning Observers . ... A History of the First Forty Years of the Amateur Astronomers Association . ... 2016 Amateur Astronomers Association of New York Designed by Press Customizr Powered by . ...