Huge Asteroid to Whiz By Earth Today at 6:28 PM
Astronomers are tracking an asteroid about the size of an aircraft carrier that on Tuesday will pass by Earth, within the moon’s orbit, in the closest approach of such an object in a generation.
The 1,300-foot-wide asteroid, known as 2005 YU55, poses no hazard, experts at NASA’s Jet Propulsion Laboratory said.
They are monitoring the spinning space rock by radar as it nears and eventually speeds past Earth at a distance of 201,000 miles. The asteroid is going 29,000 miles per hour, according to astronomers at the University of Arizona.
It is the first time since 1976 that an asteroid has come so close to Earth, and the first time astronomers have ever had this much advance notice.
By astronomers’ calculations, the asteroid is expected to make its closest approach to Earth at 6:28 pm EST Tuesday. The asteroid is too dim to be seen with the naked eye and its gravity is too weak to affect tides or earthquake activity, said experts at the National Aeronautics and Space Administration.
Its most important effect may be the adrenaline it has generated this week among the planetary astronomers tracking it through NASA’s Deep Space Network antennas, the Arecibo radio-telescope in Puerto Rico and hundreds of telescopes world-wide.
“This is an extraordinary opportunity to look at an extremely important type of asteroid,” said Donald K. Yeomans, head of NASA’s Near-Earth Object Program Office, which tracks these objects. “A small army of astronomers are pretty excited about it.”
Among the oldest objects in the solar system, such carbon-rich asteroids may hold water and important ores, as well as clues to the molecular origins of life on Earth. They also may become humankind’s next destination in space, if current plans by NASA for a manned mission to an asteroid come to fruition.
“These objects may one day be the fueling stations and watering holes for interplanetary travel,” Dr. Yeomans said.
The solar system harbors millions of asteroids, but only a few are known to cross Earth’s path, like the gigantic object that struck the planet some 65 million years ago, part of a chain of events that led to the demise of the dinosaurs. That impact left a crater 110 miles wide in Mexico’s Yucatan Peninsula, suggesting the original object was six miles or more in diameter.
By that standard, 2005 YU55 is a medium-size asteroid, among about an estimated 19,500 comparable space rocks between 330 feet and 3,300 feet wide believed to have orbits around the sun intercepting Earth’s, according to NASA’s most recent tally released in September. Some, like 2005 YU55, are rich in organic chemistry, but many are stony or more metallic. Only about a third of them have been located so far.
The asteroid 2005 YU55 was first detected six years ago and until now, researchers knew little more than its precise orbit. Previous observations suggest it is a fairly symmetrical stone sphere, darker than the color of charcoal, and rotates once every 18 hours.
NASA radar astronomers picked up its track on Friday and were immediately able to narrow its position to within one kilometer—50 times better than their previous best estimate.
“We pinged it,” said Marina Brozovic, a planetary radar astronomer who is leading the Jet Propulsion Laboratory’s team at NASA’s Goldstone radar installation that is following the asteroid. “It’s there.”
During the next 48 hours or so, the astronomers expect to map the asteroid’s surface and refine their knowledge about its orbit enough to predict its precise path well into the future. “We will probably know centuries ahead where it is going to be,” said Dr. Brozovic. “We don’t want any surprises.”
It will be 2028 before another asteroid comes so close to Earth, when the asteroid 2001 WN5 passes at a distance of about 143,000 miles.
The fly-by of 2005 YU55 offers astronomers an opportunity to rehearse their target acquisition and tracking techniques, in the event that an asteroid is ever discovered on a collision course with Earth. “We would like to know more about them in case one was found on an Earth-threatening trajectory,” Dr. Yeomans said.
CR
JPL and astronomers around the world can easily explain this phenomenon according to modern helio-centric astrophysics. However, halachos of z’manim are predicated on the universe being geo-centric, i.e. the Earth is the center of creation. How do we explain these phenomena in accordance with that model? Speeds and orbits cannot be calculated in the same manner.
reader
May be it will hit Iran’s nuclear plant.
to #2
If it hits iRAN it might me to close to iSRAEL
To #1
Read the Rebbe’s letter about the effect of general relativity on the Helli-centered vs Geo-centered models, anything that can be explained by one model can be explained in the other one, the calciulations might just be a bit (or more then a bot) more complicated but thats it
CRr
I have read that letter. The Rebbe’s argument stems from special relativity in which objects in different vectors of motion perceive themselves to be “at rest” while the others are “in motion”. And both are right.
However, according to relativity this is true for inertial bodies only, i.e. moving in a straight line. It is not true for accelerating bodies like planets in orbit around a star. So Chazrah Kasha LeDuchtah; how do we reconcile the halachic requirements with the current state of observation?
To CR
Great response. Also the Geo-centric model is the Ego-centric model.
Emess L-amito
Regardless of the model one ‘prefers’, zmanim wouldnt change.
According to the theory of relativity, the planets are relative to each other equally whether the “relative stationary (center) point” is earth or the sun.
So no, the question does not remain, ‘sunrise’ and ‘sunset’ etc would be at the same moment according to both models, as would all other calculations.
Fyi, in American high-schools students are taught that the universe ‘is’ helio-centric, and only in advanced college corses is this admitted to be a misrepresentation, and that both helio-centric and geo-centric models are equally possible. Basically they lie to most youth in school to make it sound like science has something as basic as planetary movement figured out, which they don’t.
For example, expose working watch gears, hang the watch by any one gear. and everything will move the same, with the time being the same. This can be done with any gear, the only difference is the movement of the watch assembly, not the gears relative to each other. (Bear in mind these gears also move at different speeds relative to each other. (footnote: gears in watches accelerate and decelerate, for one’s that tick vs sweep, as well as with date modifying gears.)
Choosing to falsely promote the helio-centric model as ht only valid possibility is sun-worship, since of the two, geo-centrism is at-least relative to the observer, us earthlings.