A Grand Time to Observe Mars
The 2007-2008 apparition of Mars will be one of the most favorable of the twenty first century for two reasons: Mars will be close to Earth, and. it will be above the celestial equator in our sky.
While the orbit of Earth around the Sun is very nearly circular, the orbit of Mars is not. During opposition, when the Earth and Mars lie in line with the Sun, the distance between the two planets may vary considerably from year to year depending on Mars' position in its orbit. If Mars comes to opposition when it is farthest from the Sun (at aphelion), then it will lie 61 million miles from Earth. But, if Mars reaches opposition when it is closest to the Sun (at perihelion), it will lie only 34.6 million miles from Earth. Perihelic oppositions occur every fifteen to seventeen years; the last two were in 2001 and 2003. In December of this year Mars will be six months past Perihelion and will be considered an Aphelic apparition.
The 2007-2008 apparition of Mars will be one of the most favorable of the twenty first century for two reasons: Mars will be close to Earth, and. it will be above the celestial equator in our sky.
While the orbit of Earth around the Sun is very nearly circular, the orbit of Mars is not. During opposition, when the Earth and Mars lie in line with the Sun, the distance between the two planets may vary considerably from year to year depending on Mars' position in its orbit. If Mars comes to opposition when it is farthest from the Sun (at aphelion), then it will lie 61 million miles from Earth. But, if Mars reaches opposition when it is closest to the Sun (at perihelion), it will lie only 34.6 million miles from Earth. Perihelic oppositions occur every fifteen to seventeen years; the last two were in 2001 and 2003. In December of this year Mars will be six months past Perihelion and will be considered an Aphelic apparition.
Figure 1. Graphs showing the relative positions of Earth and Mars in their respective orbits around the Sun. Left: show the seasons for each planet. Right: Shows the relative posits of each planet as it relates to cardinal points in each orbit.
Because of the way Mars' orbit is located in space, the very closest oppositions occur when we see Mars against the stars of Sagittarius and Scorpius, the southernmost constellations on the ecliptic. Thus the very best oppositions occur when Mars is too far south for good viewing in the Northern Hemisphere. This is what happened in 2003: the opposition was closest it had been in nearly 60,000 years, but Mars was low in the sky in the Northern Hemisphere. In 2007 Mars will reach opposition in the constellation Taurus just 26.5 degrees north of the celestial equator. For northern observers, Mars will be 11 degrees higher in the sky than it was for the 2005 opposition. Because the light from Mars will reach us via a shorter path through Earth's atmosphere, we will have a better, sharper view of the planet. http://www.tnni.net/~dustymars/Article_2007.htm
Focus and Cogitate: Mars Spectacular was in 2003
Mars viewing for 2007 has begun, but the red planet doesn't rise before midnight and is best seen in the hours just before morning twilight.
Here's some 2007 viewing information about the 2007 -2008 apparition of Mars.
Don't believe the Mars in August hoax! There is a message which has been floating around the internet for years about the amazingly close opposition of Mars, but the email omits the year, which was 2003. This year the text of the hoax email has changed to say Mars will look as big as the moon during the August 28th Eclipse. If you don't believe me, then wait up to see the eclipse in the wee hours of August 28th and see tiny Mars nearby. For more information on the Mars in August hoax, see the Snopes.com hoax page. If you receive the email (which maybe is why you are here), just send this link to the person who sent you the hoax. Maybe they'll send it on to everyone on their email lists. Otherwise we can all look forward to receiving the Mars in August email again every August!
This Hubble image depicts Mars in its orbit around the sun, showing the apparent relative size of the red planet. There is another great size comparison image on this page. As soon as these are updated for 2007, I'll update my links here. This year's close encounter will compare in distance to the 1999 Opposition. Mars will be 54 million miles from Earth at opposition on December 19th, 2007 and will appear as a 16 arc second diameter disk. Look on the Hubble images and see the 1999 size of Mars as compared to the 2001, 2005 planet size and distance. http://www.otastro.org/Mars2005/
Hoax or No: Mars is a Cool puzzle to think about...
Picture of Earth looking from Mars: Earth as seen from Mars by the Global Surveyor/ Credit: NASA/JPL/MSSS"Keep your eyes pealed, hold onto your teeth, it gets closer to home:"
In the year 2003, Mars was closer to Earth than any previous time in recorded human history. On August 27, 2003, Earth and Mars were a short 34,647,658 miles (55,760,000 kilometers) apart.
The two planets had not been that close in some 60,000 years. It was great news for astronomers because the Red Planet appeared unusually large in diameter. That made it relatively easy to resolve features on the martian surface with a large telescope.
In fact, Mars appeared very bright and its red-orange color was quite conspicuous. One frustration for astronomers, however, was a huge dust storm that happened to be raging over a third of Mars' surface, obscuring some features.
NASA CONCEPTION OF MARS WITH WATER FOUR BILLIONS YEAR AGO
http://www.spacetoday.org/SolSys/Mars/MarsThePlanet/MarsClosestEarth.html
No comments:
Post a Comment