Total Lunar Eclipse Draws Attention Back to the Moon
Total Lunar Eclipse Draws Attention Back to the Moon08.21.07
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Image above: This picture of total lunar eclipse was capture January 20-21, 2000.Image credit: Mr. Eclipse/Fred Espanack, www.mreclipse.com.
As August draws to an end, watchers of the night sky will be in for atreat. In the early morning hours of August 28, sky watchers acrossmuch of the world can look on as the Moon crosses in to the shadow ofthe Earth, becoming completely immersed for one-hour and 30 minutes, aperiod of time much longer than most typical lunar eclipses. In fact,this eclipse will be the deepest and longest in 7 years.
The event begins 54 minutes past midnight PDT (3:54 a.m. EDT) on August28. At first, there is little change. The outskirts of Earth's shadoware as pale as the Moon itself; an onlooker might not even realizeanything is happening. But as the Moon penetrates deeper in to theEarth’s shadow, a startling metamorphosis occurs. Around 2:52 a.m. PDT(5:52 a.m. EDT) the color of the Moon changes from moondust-gray tosunset-red. This is totality, and it lasts for almost 90 minutes.
With the Sun blocked, you might expect utter darkness, but instead theground at your feet appears to be aglow. Why? Look back up at Earth.The rim of the planet seems to be on fire. Around the Earth'scircumference you will witness every sunrise and sunset in theworld—all at once. This incredible, colorful light beams into the heartof Earth’s shadow, transforming the Moon into a landscape of coppermoondust and golden hills.The eclipse will be visible from Australia, parts of Asia and most ofthe Americas, but not from Africa or Europe. The view is different fromeach location on the planet. Here in the United States, Pacificobservers are favored. For them the entire eclipse will unfold high inthe post-midnight sky. However, on the East Coast, totality will be cutoff early by sunrise.
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Image above: This map shows the start times for viewing the eclipse for the time zones of the United States.Image credit: NASA.
Here is some of what you can expect to see from various locations across the country:
[*]Viewers on the West Coast will get the best show. For them theentire eclipse will be visible from start to finish before moonset inthe early morning hours of Tuesday, August 28, 2007.[*]Hawaiians will be able to see the full eclipse, or totality, around midnight.[*]For viewers on the East Coast and in the Great Lakes States, theeclipse will start around dawn and will still be occurring when the Sunrises and the Moon sets that morning.[*]Finally, across the Mid-West, Plains, and Rocky Mountain States thetotality has already ended before the Moon sets and viewers there willonly see a partial eclipse as the Moon emerges from the shadow of theEarth.While sky watchers focus their attention on the eclipse, NASAscientists and engineers are looking at the Moon for a differentreason. NASA is getting ready to take its first steps back to the Moon,nearly 40 years after the first human Moon landing.
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Image above: Totality is embraced by the partial phases of the 2000 total lunar eclipse. Image credit: Mr. Eclipse/Fred Espanack, www.mreclipse.com.
Next year NASA will launch the Lunar Reconnaissance Orbiter (LRO) tocompile the first all digital, next generation maps of the Moon, whichwill measure topography, temperature, resources, and hazards. Althoughit is the Earth’s closest neighbor, scientists still know relativelylittle about the Moon, aside from the six Apollo human landing sites.LRO will dramatically change all that by acting like a "chart-making"Renaissance-era explorer. It will reveal the mysteries of the lunarpolar regions while also evaluating from above the changes that havetaken place since humans left the lunar surface in December 1972, whenApollo 17 blasted off to return to Earth.
LRO is the first mission in an endeavor to extend a human presence intothe solar system, starting with a return to the Moon. Returning to theMoon will enable the pursuit of scientific activities that address ourfundamental questions about the history of Earth, the solar system andthe universe - and about our place in them, including aspects of thesearch for life beyond our home planet.
http://www.nasa.gov/images/content/187109main_eclipse-lro_250px.jpgImage right: Image of the LRO spacecraft in orbit around the Moon Image credit: NASA.
LRO is a robotic mission designed to create a boldly new type ofcomprehensive, digital map of the Moon's features and resources,necessary to cost-effectively engineer a human outpost on the Moon. LROfollows in the footsteps of the robotic predecessors to the Apollohuman missions - missions designed in part to search for the safestpossible human landing sites (such as the Ranger, Lunar Orbiter andSurveyor missions). However, the goals of LRO go far beyond therequirements of these previous missions.
LRO focuses on the selection of safe landing sites, identification oflunar resources, and the study of how the Moon’s environment willaffect humans. In particular, LRO will explore the nearly unknown lunarpolar regions, which may prove ideal settings for a sustainable humanoutpost thanks to nearly constant sunlight and potential resources.LRO’s topographic mapping of the Moon will usher in a new era of Earthand planetary remote sensing, and potentially catalyze solutions ofbenefit here on Earth, as scientists measure the signatures of climatechange.
LRO is scheduled for launch in fall of 2008 on an Atlas V 401 rocket.The spacecraft’s final orbit will be a circular polar orbitapproximately 50 km above the Moon's surface (just over 30 miles),closer than any other lunar mission. Indeed, the LRO "vantage point"will be somewhat like flying in a high-altitude airplane around Earth,mapping as it goes.The August 28 eclipse will be a spectacular site, drawing the attentionand curiosity of people around the world to the Moon. While there isstill much to learn about this planetary body, NASA is taking the firststeps to uncover the Moon’s remaining mysteries. The Moon will foreverbe linked to the history of Earth and, thanks to events such as thisyear’s enthralling eclipse and the upcoming LRO mission, we can allparticipate in a new era of lunar exploration.
Information extracted from NASA website
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