Today Tuesday and Wednesday Discovery Enterprise will join the rest of the world in observing the last transit of the planet Venus for this century. After June 5/6th, 2012, the next transits of Venus will be in December 2117 and December 2125.
Join us for the live coverage for this spectacular celestial event.
Join us for the live coverage for this spectacular celestial event.
The transit or passage of a planet across the face of the Sun is a relatively rare occurrence. As seen from Earth, only transits of Mercury and Venus are possible. On average, there are 13 transits of Mercury each century. In contrast, transits of Venus occur in pairs with more than a century separating each pair.
The last Venus transit was in June 8th, 2004 so the second event of the pair will occur on Wednesday, June 6 (Tuesday, June 5 from the Western Hemisphere).
The entire event will be widely visible from the western Pacific, eastern Asia and eastern Australia as shown in figure below.
Most of North and Central America, and northern South America will witness the beginning of the transit (on June 5) but the Sun will set before the event ends. Similarly, observers in Europe, western and central Asia, eastern Africa and Western Australia will see the end of the event since the transit will already be in progress at sunrise on June 6th from those locations.
Much of the world will be able to witness a rare celestial event on June 5-6, as Venus crosses the face of the sun in a spectacle that will not be visible again for more than a century. But for anyone who is not able to see the so-called transit of Venus in person, there are other ways to catch the historic event online.
While observers in many parts of the world, including North America, Europe, Asia and eastern Africa, will be well-placed to see at least part of the transit in person, several organizations are planning to broadcast live views using footage from various observatories and telescopes around the globe. See Space.com for a guide to online webcasts and an excellent infographic concerning this rare celestial event.
NASA, in particular will be hosting a live Sun-Earth Day webcast on June 5 that will last the entire length of the Venus transit. The footage will stream live from the summit of Mauna Kea, Hawaii, with accompanying commentary from various experts. Times are subject to change, but the webcast is currently scheduled to begin at 5:45 p.m. EDT (21:45 GMT).
Another major first for this transit will occur high above Earth, when astronaut Don Pettit becomes the first human to witness and photograph a transit of Venus from space. His images and commentary will be streamed to Earth during the crossing.
The 2012 transit will give scientists a number of research opportunities. These include:
Measurement of dips in a star's brightness caused by a known planet transiting a known star (the Sun). This will help astronomers when searching for exoplanets. Unlike the 2004 Venus transit, the 2012 transit occurs during an active phase of the 11-year activity cycle of the Sun, and is likely to provide practice in detecting a planet's signal around a "spotty" variable star.
Measurement of the apparent diameter of Venus during the transit, and comparison with its known diameter. This will give information on how to estimate exoplanet sizes.
Observation of the atmosphere of Venus simultaneously from Earth-based telescopes and from the Venus Express spacecraft. This will give a better opportunity to understand the intermediate level of Venus's atmosphere than is possible from either viewpoint alone, and will provide new information about the climatology of the planet.
Spectrographic study of the atmosphere of Venus. The results of analysis of the well-understood atmosphere of Venus will be compared with studies of exoplanets with atmospheres that are unknown.
The Hubble Space Telescope will use the Moon as a mirror to study the light reflected from Venus to determine the makeup of its atmosphere. This may provide another technique to study exoplanets.
Join us for this fantastic event:
Join us for this fantastic event:
Venus Transit: Live from Keck Observatory
Streaming live video by Ustream
NASA Webcast of the June 5/6th 2012 Transit of Venus.
Video streaming by Ustream
Science Casts: The 2012 Transit of Venus
Science Casts: ISS Transit of Venus
No comments:
Post a Comment