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Earth's Nonexistant Second Moon

While this isn't a dreary polemic against the Internet, there are times that relying on Internet information not only leaves a bit egg on your face but an entire gooey cheese omelet. Last year we had a doomsday scenario about an asteroid which passed so close to the Earth that it might hit the Earth on its next pass in 2028. Well it turns out that if the astronomers had taken the time to check earlier pictures of this asteroid and had calculated the orbit using all of the known information instead of just a few data points that it would become obvious that the asteroid was no danger to the Earth. However hysterical statements were all over the Internet before cooler wiser heads had a chance to do their deliberative thing.

Well, this week somebody let toddlers make Sunday brunch again and eggs have coated everybody head to foot. An observatory with a grant from NASA to watch near Earth orbit asteroids announced "Breaking News - the Earth has a Second Moon" to all and sundry. Once again the source seemed creditable (and indeed it was from a reputable observatory) but the Internet moves so fast that the retractions never catch up with the initial statement.

What the observatory detected was a school bus sized object in an orbit about 1.7 times as far from the Earth as the Moon. They came up with calculations based on five days of observations which allowed them to "determine" that the new moonlet must have been an asteroid which passed too close to the Moon last August and was captured by the Earth. The object was given the designation 2001-DO47. Further calculations "determined" that in a subsequent encounter with the Moon this upcoming August that the asteroid would be accelerated until it left the vicinity of the Earth.

Everyone jumped on the bandwagon but at the end of a week 2001-DO47 had been demoted from a second moon to a spacecraft. It seems 2001-D)47 was nothing more nor less than the solar wind monitoring station "WIND". Far from being in an unstable orbit, the spacecraft is at the so-called L1 point where the Sun's and the Earth's gravity balance. This allows the spacecraft to stay put down wind of the Earth without using excessive amounts of fuel.

The real problem with this stuff is that it has a life of its own. This misinformation is tucked away in a thousand places on the Internet. Sure as you're born, it will show up in some science report by some student sometime in the not too distant future. It isn't just 14 year old boys playing the stock market who fill the Internet up with bogus information, it is reputable organizations who forget that public messages far outstrip retractions. So about all I can suggest is to remember Sportin' Life's ironical song from Porgy and Bess - It Ain't Necessarily So! Remembering that may allow you to avoid some of the egg omelet that astronomers are busily washing off their faces.

Spring brings several new types of objects into view. In the triangle formed by the constellations of Leo (Lion), Virgo (Maiden) and Coma Bernices (Bernice's Hair) is the great Virgo super cluster of galaxies. These range from small galaxies less than a hundredth the size of our own Milky Way Galaxy to huge galaxies with over a thousand times as many stars. Venus will begin to set earlier every evening as it catches the Earth from behind. Jupiter and Saturn will remain high enough to be easily seen, but don't wait until too late in the evening because they set before midnight now.

If you are hardy enough to stay up very late, or you rise while it is still dark, look in the southern sky for two reddish points of light in the constellation Scorpio. One point is Mars (called Ares in the ancient Greek language) and the other is Antares which comes from the words "anti" and "Ares". Usually this is translated as "the rival of Mars", but I prefer the alternate explanation. "Anti" can mean opposed or not. I can imagine some ancient Greek saying to a friend "There is the planet Ares" only to have the friend say "That is not Ares." Today the title sticks.

Leslie Coleman
Leslie Coleman
Entry Date:
Mar 1, 2001
Published Under:
Leslie Coleman's Columns
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