Eros is coming! 433 Eros, the asteroid that allowed astronomers to measure the distance of the Sun, makes its closest approach since 1975 in January/February 2012
A mosaic image of 433 Eros made by the NEAR Shoemaker spacecraft on 29 February 2000 while circling the asteroid. The asteroid is roughly a cylinder in shape with a length of 34 km and a diameter of 11 km. Image courtesy NASA/JPL/JHUAPL
The asteroid 433 Eros is of great historical significance for its close approaches to Earth enabled astronomers to make an accurate measurement of its distance and hence the distance of the Sun to Earth. The value of the solar distance provided by observations of Eros, ended two centuries of effort to determine that distance using observations of theTransit of Venus.
The asteroid is making its closest approach to Earth in 37 years in late January and early February in 2012. Having this event in the same year as a rare transit of Venus is a fortuitous historical coincidence.
The minor planet or asteroid 433 Eros was discovered by two astronomers, Gustav Witt at Berlin and Auguste Charlois at Nice, on the night of 13 August 1898. When astronomers calculated the path of the newly discovered asteroid around the Sun they realised that the path has the shape of a somewhat elongated oval and the asteroid’s average distance from the Sun is less than that of the planet Mars. These two factors mean that that Eros can on occasion come relatively close to Earth providing an opportunity for its distance to be measured accurately.
The approach of Eros in January/February 1931 was a particularly favourable one with a minimum distance from Earth of about 25 million km. Before the event the Royal Greenwich Observatory astronomer Harold Spencer Jones explained in the Astronomical Journalwhat kind of observations were necessary to secure the distance of Eros:
1. Observations taken at a single observatory in the evening and in the morning or
2. Observations secured simultaneously at two observatories in approximately the same
latitude but differing several hours in longitude or
3. Observations secured simultaneously at two observatories at approximately the same
longitude but differing as widely as possible in latitude.
2. Observations secured simultaneously at two observatories in approximately the same
latitude but differing several hours in longitude or
3. Observations secured simultaneously at two observatories at approximately the same
longitude but differing as widely as possible in latitude.
The position and path of 433 Eros on 1 February 2012 with respect to the Earth, Mercury, Venus and Mars. Courtesy JPL Small-Body Database Browser
In 2012 Eros will not approach quite as closely as 81 years earlier, but at a distance of 26.7 million km it is still a fairly close approach. Of course, there is nothing to fear and there is no risk whatsoever to the planet Earth.
In late January and in early February 2012 amateur astronomers should easily be able to find Eros with a small telescope. Its magnitude at that time is expected to be 8.6 which should be bright enough to ensure visibility despite a bright Moon that ranges in phase from first quarter on 31 January to full on 8 February 2012. In the early evening after dusk Eros is low in the eastern sky.
For those with setting circles on their telescopes, the coordinates on 31 January (from the BAA 2012 Handbook) are 10 hours 33 minutes 19.0 seconds RA and -4° 48’ 23” declination. On 10 February the RA is 10 hours 20 minutes 27.6 seconds and the declination is -14° 38’ 49 seconds.
To those with small telescopes, good luck in finding and observing Eros!
Postscript: There is now a good finding chart, created by Sky and Telescope magazine, that will help you locate 433 Eros in the sky. For Australian use invert the chart and look due east in the evening around 10:00pm to see Leo rising. Each dated tick-mark shows the position at 11:00am EAST for that date. Use these tick-marks to estimate the asteroid’s position, then look through your telescope for the extra ‘star’ -Andrew Jacob
Abandon
all your possessions and run for the hills: It has been foretold
that the world is coming to an end sooner than you think, in the year
2012. It seems that you can't pick up any newspaper or magazine
without reading that the apocalypse is almost upon us.
What
really is going to happen in 2012? Asteroid 433 Eros is going to pass
within 17 million miles of the Earth in January; the United States
will hand over control of the Korean military back to the Koreans in
April; there will be an annular solar eclipse in May and a solar
transit of Venus in June; the Summer Olympics will take place in
London; the Earth's population will officially pass 7 billion people
in October; the United States will elect a new President in November;
construction of the new Freedom Tower will be complete in New York
City; the sun will flip its magnetic poles as it does at the end of
every 11-year sunspot cycle; and, as I'm sure you've heard by now,
the Mayan calendar completes its 5,125 year cycle, presumably
portending the End of Days.
Mayans
had three calendars. They had a solar calendar that was 365 days
long, and a ceremonial calendar that was 260 days long. These two
calendars would synchronize every 52 years. To measure longer time
periods, they developed the "long count" calendar, which
expressed dates as a series of five numbers, each less than twenty;
something like the way we measure minutes and seconds as a series of
two numbers each less than sixty. And, just in case this might seem
too simple, for some reason the second to last number was always less
than eighteen. The first day in the Mayan long count calendar was
expressed as 0.0.0.0.0, and by our calendar, this was August 11, 3114
BC. Every 144,000 days (or about every 395 years, which they called
a baktun),
the first number would increment, and a new baktun would
start. Recall how we all got to enjoy the excitement on the
millennium of watching the digital displays roll over from 12/31/1999
to 1/1/2000? Well, that's what's going to happen on December 21, 2012
to the Mayan calendar. It's going to roll over from 12.19.19.17.19 to
13.0.0.0.0, just as it has done each of the previous twelvebaktuns.
There's no archaeological or historical evidence that the Mayans
themselves expected anything other than a New Year's Eve party to
happen on this date: Claims that this rollover represents a Mayan
prediction of the end of the world appear to be a modern pop-culture
invention. It's true that the Mayan carvings of their calendar only
depicted 13 baktuns,
but what did you expect them to do? Carve an infinitely long calendar
every time they wanted to express a date? The explanation could be as
simple as they didn't expect people in the 21st century to still be
obsessed with their archaic calendar.
Another
story predicting doom in 2012 says that a new planet, variously
described as Planet X, a planet/comet (which makes no sense), or the
planet "Nibiru" is going to pass so close to the Earth as
to cause earthquakes and tidal waves and all kinds of destruction,
possibly even flipping the Earth completely upside down. This is an
urban legend that's been around for a long time, but for most of the
story's history, this was supposed to happen in May of 2003, as any
Internet search for "Planet X" will reveal. Apparently what
happened is that the Planet X advocates, perhaps embarrassed or
disappointed that 2003 passed without incident, heard about the much
more popular Mayan calendar story, and decided that 2012 is close
enough to 2003 that it must be the correct date and that the Planet X
destruction is probably what the Mayans were foretelling. The Planet
X legend got started by misinterpretations of astronomical
observations combined with an ancient Sumerian carving that has been
erroneously interpreted to depict a solar system with ten planets.
Why the craftsmen who made carvings in ancient Sumeria should be
presumed to have planetary knowledge superior to that of modern
astronomy is not convincingly argued. If you're interested in all of
the actual science behind the Planet X story, there's no better
source than Phil
Plait's "Bad Astronomy" blog, which goes into all the
facts, rumors, and sources in detail.
Here's
one more reason people are frightened about 2012. About 500 years
ago, Copernicus confirmed what Hipparchus had observed in 2200 BC:
that the axis of the Earth, which leans over at 23.5°, completes one
full rotation every 25,765 years. This means that in 12,000 years,
Christmas will come to Australia in winter and the northern
hemisphere will depict Santa in Bermuda shorts. Astrologers call this
period a Great Year, and they divide it into 12 Great Months or
astrological "ages", each about 2,147 years long. Each age
corresponds to one of the signs of the zodiac. We are currently in
the Age of Pisces, and like the song says, we're soon going to enter
the Age of Aquarius. According to modern official delineations of the
edges of the constellations, we'll move into the new age in the year
2600. But there's some disagreement, and some astrologers place it at
2595, 2654, or 2638. A few put it much earlier, as soon as 2150 or
even 2062. However, once the news of the Mayan calendar broke, a
large segment of the astrological community abandoned the official
constellation definitions and stated that the Age of Aquarius will
begin in 2012. So, you can call this a third major reason why the
world will end in 2012, but you have to be awful loose with your
astrology, and you also have to think of some reason why the dawning
of the Age of Aquarius might bring on the end of the world. I have
not found any plausible claims for how it might have this effect.
So
that's a lot of reasons, weak though they might be, to predict that
the we're all going to die in 2012. However, there's one significant
fact that the 2012 doomsayers all seem to forget: Despite all the
various 2012-ish predictions for the end of the world, there are
far more stories
of apocalypse with different dates.
For example, popular interpretations of Nostradamus found predictions
for the end of the world in July of 1999, December of 1999, June of
2002, and October of 2005. It's also been said that his writings
could mean the dead will rise from their graves in either 2000, 2007,
or the year 7000. Nostradamus never said anything about 2012.
Many
Protestant Christians believe that the end of the world will come in
the form of what they call the Rapture, when the righteous will all
be whisked away to heaven. Shakers believed the Rapture would come in
1792. Seventh Day Adventists first calculated it would happen in
1843, then when nothing happened, they found an error in their
calculations and corrected it to 1844. The Jehovah's Witnesses made
firm predictions for 1918, 1925, 1941, 1975, 1984, and 1994. A book
was published in 1988 called 88
Reasons the Rapture is in 1988.
A number of Bible scholars found firm scriptural evidence that the
Rapture would happen in October of 2005. Thousands of Koreans gave
away all their money and possessions in preparation for the Rapture
on October 28, 1992. Even Sir Isaac Newton made a calculation based
on scripture that showed the Rapture could not happen before 2060.
Some Jewish scholars place the "end of days" via Armageddon
in the year 2240. I couldn't find 2012 mentioned in any of these
stories.
In
fact, James Randi's magnum opus publication An
Encyclopedia of Claims, Frauds, and Hoaxes of the Occult and
Supernatural lists
44 distinct end of the world predictions that all came and went
unfulfilled. Why should we think that the 2012 legends are any
different? Any examination of the science behind any of the stories,
even a glib examination, reveals a complete absence of plausible
foundation. Only the Planet X story, which is the most easily
falsified as it depends on concrete astronomical observations that
are demonstrably false, offers a proposed mechanism for exactly how
this "end of the world" is to be accomplished, the alleged
gravitational destruction. Neither the Mayan calendar people, nor the
Age of Aquarius people, have offered any claims for how or why the
world will end, only that their particular legend points to a
rollover in some ancient calendar. My calendar rolls over every time
the ball drops in New York, and I've yet to see this cause any
planetary cataclysm, except for the guy who has to mop out the drunk
tank at the NYPD.
Many
people tend to place more trust in ancient neolithic traditions than
in the observations of modern science. There's nothing wrong with
studying and respecting our predecessors' history for what it was,
but when you turn things over and start believing that scientific
knowledge of the natural world has only decreased over time, you're
not doing anyone any favors. Source:
This is March 18 2012 & we are still here, Homer!
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