From the results of the fear of the end of the world * Prepare the binoculars
Avishai Gal-Yam
In the last week of July, a mirror may be revealed to astronomy enthusiasts
Rare: in the evening hours a comet, whose full name is supposed to appear in the western sky
"Comet 1999 S@4 Linar" (and its nickname, for short, "Comet Linar").
Because this is probably the first time this comet has come close to us
In its orbit around the sun, it is difficult to accurately predict how bright it will be in the sky,
But there are many chances that Linar will be the first possible comet
to notice it without a telescope since the Hale-Bopp comet passed our name before me
More than three years: Astronomers specializing in observations of comets
It is estimated that viewers who will be located in particularly dark areas will be able to distinguish
in the comet with the help of binoculars, on the days when its brightness will be greatest,
Around July 23rd.
The appearance of comets in the sky was one of the astronomical phenomena
which have received much attention since the dawn of human civilization. Comets are
Small bodies that are mostly composed of ice and spend most of their time in orbits
are very far from the sun, so that they cannot be noticed at all. the assumption
It is accepted today that the comets are a remnant of the disc of primordial material
from which the planets were formed.
The famous Dutch astronomer Jan Ort showed that it is probable that the origin of
The comets in a distant region on the outskirts of the solar system (now named after him -
"Ort cloud"), where there are millions of blocks of ice "dirty" in dust.
The gravitational pull of a passing star occasionally results in one of these bodies
fall towards the sun - and this is how a comet is formed.
When a comet approaches the sun, the sun's heat causes the trapped gases to be released
inside his body, and thus a "halo" of gas is formed around him. Some of the gas in the halo
is affected by the flow of particles emitted from the sun, known as the "solar wind", and becomes
to the tail of the comet which gives it its characteristic appearance.
Since comets contain large amounts of water it has been hypothesized,
Because the impact of comets on planets, such as Earth or Mars, is
The source of water on these stars. If that's the case, then Comets made it possible
the creation of life on earth. On the other hand, the impact of a large comet
on Earth may lead to catastrophic results - earthquakes,
Floods, volcanic activity and severe impact on
Atmospheric. Some argue that the impact of celestial bodies such as stars
Comets have previously caused the mass extinction of animals on Earth (Mass
Extinction Events), including the dinosaurs.
Since then, the astronomer Sir Edmund Halley discovered that the comet, since then called
His name, which reappears in our name cyclically every 75 years or so, has changed
The search for comets is a popular occupation among professional astronomers
and lovers Until recent years, most comets were discovered by "hunters
Comets" - astronomers who specialized in the search
New comets in the night sky, an occupation that requires long and dedicated observations
And an unusual familiarity with the night sky. Since the days of Halley, the union
The International Astronomer usually names new comets after their discoverers.
This is how the bright comet is named after its discoverers - Bopp Hale and the comet
The famous Shoemaker-Levy, which hit the planet Jupiter in 1994
This state of affairs has changed in recent years: the number of new comets
Those who are discovered each year increases many times over, and most of them are no longer discovered
By the "comet hunters". Most new comets are discovered by a few
Large groups of scientists, using robotic telescopes and methods
Advances in digital image processing to computer-detect objects
Moving in the sky, like comets. The comet that will approach the Earth at the end of July
Discovered by one such computer robotics project: Project ..LINEAR
LINEAR, acronym for "Lincoln Program for Asteroid Research
"Research Lincoln Near Earth Asteroids", is
One of the most prominent and important projects of this kind, and is centered in the laboratories
Lincoln at the Massachusetts Institute of Technology in the USA. The project is funded by
by the American Air Force and uses a telescope, which the Air Force followed
using it in the past after Soviet satellites. Now the telescope follows me
Celestial objects such as asteroids and comets.
The project is one of a series of similar projects that started operating in the countries
The alliance in recent years, after the American House of Representatives recognized it,
That the danger that a celestial body will hit the earth and cause enormous damage - witness
To risk the continued existence of humanity - deserves the attention of the government,
and allocated millions of dollars to research that would allow early warning and prevent incidents
Such.
The goal of "Linar" and the other projects is to locate all the bodies
The small ones in the solar system that may pass near the earth and determine the
their routes. Most of the bodies that could hit the Earth are
Asteroids - blocks of rocks and metals, moving in the inner part of a system
The Sun, mainly between the orbits of the planets Mars and Jupiter. in a way
In principle, even a comet may endanger the earth, but such bodies
much rarer.
The Linar project has so far discovered about 60 new asteroids, of which 400
From which were defined "objects close to the Earth" (@Objects NEOs - Near
Earth), i.e. those whose orbit may pass dangerously close to the globe
Country. With the same means, the project personnel also discovered more than 40 comets
new ones Thus, as a byproduct of the project, the "Linar" researchers became
For the most prolific comet explorers.
Also at Tel Aviv University's Wise Observatory there are participants
In the global effort to locate and track near-Earth objects. Eran
Ofek and writes these lines, together with Ilan Manolis from the Israel Association
For astronomy, trying to locate pale asteroids to characterize the
The asteroid population that is not being monitored by the projects
The big ones, like "Linar", are only sensitive to brighter asteroids.
Comet Linar does not currently endanger the inhabitants of the Earth; Although he is supposed to
to pass relatively close to the earth, the only contact between the inhabitants of the earth
His understanding will take place through those of us who will observe at the end of the month, in the hours
Tonight, towards the northwest. Such viewers may gain a heavenly sight
Special and rare, which has thrilled mankind since the dawn of history - the appearance of a star
A comet passing in the sky.
