On Friday, August 1, a total eclipse of the Sun took place within a narrow corridor that traverses half the Earth. We couldn't see it from the U.S. except via TV and the Web. The sight thrilled millions, however, seeing it with their own eyes or remotely, via electronic means.
On Friday, August 1, a total eclipse of the Sun will be visible from within a narrow corridor that traverses half the Earth but you won't be able to see it from Ohio! The path of the Moon's umbral (central) shadow begins in Canada and will speed across northern Greenland, the Arctic, central Russia, Mongolia, and China. A partial eclipse is seen within the much broader path of the Moon's penumbral shadow, which includes far northeastern North America, most of Europe and Asia. No portion of the eclipse will be visible from the United States that day!
It's summer time where the Phoenix lander sits at what would be the Martian arctic circle. Its mission is limited to only around 92 (Earth) days because, even as it sits there in Mars's summer season, the high temperature never exceeds something like 20 degrees (F) below zero and, at night, well, your ice cream would never melt. EVER! They tell us that, as winter sets in on Mars, the Phoenix lander will become entombed, yes completely covered in snow and ice --mostly frozen carbon dioxide-- effectively "killing" the immobile robot about three (Earth) months from now. When summer returns to the northern regions of Mars, the lander will be exposed again. The solar panels will generate electricity again. And NASA will listen. There is a small chance Phoenix will stir back to life and, if it does, her handlers don't want to miss it! In the mean time we sit and watch the show from the warmer climes of Earth and marvel.
We're landing on Mars this Sunday. Well, at least a mechanical emissary of ours is landing on the Red Planet this Sunday, May 25.
Saturday, May 10: Celebrate Astronomy Day by taking a look at the night sky. After dark, say around 9:30 to 10:00, under --we hope-- a clear sky, look in the direction of the first-quarter Moon. To the lower right of our pock-marked neighbor you will see three bright "stars" floating in the still darkening sky. The first of those isn't a star at all. That first reddish object is the planet Mars. To the right of that are two of the genuine article: stars Pollux and Castor, the "head" parts of the constellation Gemini. Higher in the sky, nearly overhead, the ringed planet Saturn can be seen to the east of the star Regulus; the pairing makes them easy to spot. Look carefully: can you see the slightly golden tint to Saturn's light compared with the star's cooler color?
"Live" eclipse webcasts
Too cold to stand outside? Clouds covering the Moon? Watch from the comfort of your keyboard! During the eclipse (see info at right margin) check out the following links recommended by SpaceWeather.com for "live" webcasts of the event. Of course, if the weather is clear be sure and take a look at the eclipse from your own back yard... there's nothing like seeing it with your own eyes! See my earlier post about the eclipse for more information and online resources. Note: there's an error in that post... the Moon will begin to brighten in the wee hours of Thursday morning, NOT Sunday!
Live webcasts: from the Canary Islands; from Norway; from Iran; from Columbus, Georgia; from the Netherlands; from Belgium; from Spain; and another from Spain.
The weather isn't looking promising but weather or not {get it?} the sky cooperates, there will be a total lunar eclipse Wednesday night, Feb. 20. Given clear skies, it's a show not to be missed and it's a "prime time" event!
You can get a great view of it from their own back yard without need of a telescope. If the sky is clear just step outside and look at the Moon at about 9 PM when the eclipse (technically already underway) should begin to become noticeable. Check back occasionally over the next hour or so as the Moon moves deeper into Earth's shadow. Adding to the spectacle will be the bright ringed planet Saturn which will shine like a golden star near the then-darkened Moon. By 10:00 the Moon will be in full eclipse. It won't begin to brighten again until about 11:00 and will be back to its full brilliance in the wee hours of Sunday morning.
The next total lunar eclipse visible from here will take place in the early morning hours of December 21, 2010.
An observing chart and more details are available via several online sources. Here are two very good resources:
Refined orbital calculations brought good news for Martians, disappointment to scientists...
From the NASA/JPL Near-Earth Object Program Office -- January 9, 2008 -- Since our last update, we have received numerous tracking measurements of asteroid 2007 WD5 from four different observatories. These new data have led to a significant reduction in the position uncertainties during the asteroid's close approach to Mars on Jan. 30, 2008. As a result, the impact probability has dropped dramatically, to approximately 0.01 percent or 1 in 10,000 odds, effectively ruling out the possible collision with Mars. Our best estimate now is that 2007 WD5 will pass about 26,000 km from the planet's center (about 7 Mars radii from the surface) at around 12:00 UTC on Jan. 30th. With 99.7 PERCENT confidence, the pass should be no closer than 4000 km from the surface.
You may have seen news headlines referring to an asteroid possibly to hit or "threatening" Mars. It is true that a space rock, about 164 feet across, could hit the Red Planet on January 30. The event isn't a certainty, however, and if it does happen Mars will survive relatively unscathed. At first the odds of an impact were said to be 1 in 75. Recent analysis of other observations has refined the asteroid's orbit and the odds are now at 1 in 25. Astronomers will continue to narrow the odds between now and the end of January and will know in advance and for certain whether Mars will take a hit.
If the asteroid were to hit Mars the result would be a large crater (perhaps half a mile in diameter) but the planet as a whole would be largely unaffected -- Mars is half the size of Earth but it's still much bigger than the house-sized asteroid (if you have a really big house). In fact many space scientists hope the collision takes place because it would provide insight into the makeup of Mars and the dynamics of such a large event. Several spacecraft are currently in orbit around Mars and could make unprecedented observations of the impact and/or its aftermath. The two still-functioning Mars rovers would also make observations. Only space-based and, perhaps, the largest of ground-based telescopes have any chance of seeing the collision, if it happens at all.
Better Mars than us: The energy released by a 164-foot asteroid hitting Earth would cause untold destruction if it impacted anywhere near a population center. In June of 1908 an object believed to be of about the same size as the one we are discussing exploded over Siberia with a yield equivalent to a 10- to 15-megaton nuclear device. The "Tunguska Event" felled an estimated 80 million trees over 830 square miles. Today's tracking of the Mars-bound rock reminds us that there are still dangers "out there" of which we need to be aware and with which we may one day need to cope.
Mars opposes Earth?
It's not really a rivalry. About every 26 months planet Earth passes between the Sun and sister planet Mars. It's also a time when the two worlds are closer together than normal. Because the orbits of the planets are not perfectly circular, the date of opposition and the date of closest approach aren't usually the same and the distance at its closest also varies.
This year the closest approach of Earth and Mars will take place on December 18 when they will be just shy of 55 million miles apart. Opposition takes place December 24 and Mars will be at its brightest for Earth-bound viewers. The close approach and brightness makes viewing the Red Planet its best during opposition and near-opposition periods.
