In addition to the planets, satellites and asteroids, comets solar system hosts.
Comets roam deep space several light years from the Sun and from time to time one of them comes to visit us. For these small spheres of ice traveling between the stars, some are captured by the gravitational force of the Sun. The number of captured comets that periodically return is around 2000. We can say that comets are big stones wrapped in dirty snow mixed with dust, with a highly eccentric elliptical orbit around the Sun. The most famous periodic comet is Halley's comet approaches the Sun every 76 years. In 2013 we could see the most beautiful and brightest comet in history, two astronomers from Russian and Belarusian Artyom Novichonok and Vitali Nevsky. Their discovery made in September 2012 in Kislovodsk in Russia, called Ison.
In October 2012, the comet Ison is far from Earth, beyond the orbit of Jupiter whose aphelion is 816,620,000 km from the Sun. It is only when it plunges towards the Sun that we can observe the characteristic white trail of comets.
When a comet approaches the Sun, the outer layer vaporizes and forms a gaseous envelope (coma). Solar radiation exerts pressure on the coma and forces the particles and gases away from the Sun then forming a glowing tail of ionized particles. It seems that the comet will Ison very close to the Sun at only 2 million miles, it will be a beautiful sight for months.
According to astronomers, the comet Ison will be visible November 2013 to January 2014, with a maximum brightness of 29 November 2013.
Early October 2013, it will close to Mars and may be observable by the rovers and orbiters.
However, this cosmic journey to the comet Ison could be his first and last trip to the Sun, as we approach the Sun, it could disappear, according to NASA scientist and expert Karl Battams comets, "Coming from the cloud Oort, this could well be his first encounter with the Sun. If this is the case, surely it is full of ice intact highly volatile and could never have faced real gravitational or thermal stresses. it could therefore very well explode and evaporate weeks, even months, before brushing the Sun. "
Historically, comets shine with a brilliance scary in the memory of mankind because they have long been a misfortune and disaster.
They are also harbingers of upheaval.
In 2013 humanity will still economic crisis, Ison could ignite our imagination.
But for scientists, it is not the messenger of misfortune, it is the guardian of the past, which holds the keys of our origin.
Comets are wandering the sky, the messengers of interstellar space travel as dirty icebergs swarming primordial matter.
Ison comet was observed by Russian amateur astronomers in September 2012 and pass close to the Sun, to 1.17 million kilometers, 28 November 2013. Ison will be so close that it will reach a temperature of ≈ 2700 ° C, according to the Institute of Celestial Mechanics ( IMCCE ) of the Observatoire de Paris. If it resists this temperature we can observe even in daylight from early December. NASA announced that ISON increase to ≈ 64 million km from the Earth on December 26. But astronomers are struggling to confirm these predictions because they do not know if it will withstand the tidal forces of the Sun. Ignacio Ferrin , astrophysicist in Medellin (Colombia) said that the ISON light spectrum shows that it will break. "This disintegration will occur before it reaches perihelion, the closest point to the Sun," he said. Other astronomers say the comet ISON is likely to survive his encounter with the Sun.
And 9 October 2013, the Hubble Space Telescope, shows us still intact ice core of the comet (see image right). We still do not know precisely the diameter of the core, initially estimated at between one and four kilometers. It will be difficult for this small rock to resist the pressure and infernal heat of the Sun. That the comet broke up or not, we will see in our winter sky, the most magnificent end of 2013, that of melting ice, which produces the long comet tails.
On 29 November 2013 the comet Ison will pass very close to the surface of the Sun, 1.2 million km and will reach at this moment, its maximum brightness. The radius of the Sun is 700,000 km, this gives an idea of its proximity to the Sun. It will therefore suffer huge thermal and gravitational constraints and we don't yet known how the small comet will react. Its core will certainly "boil" and release gigantic jets of gas and dust that will feed its shining tail. If the comet does not disintegrate, it will pass closest to Earth on December 26, at ≈ 64 million km.
November 16 Ison is further away from the Sun, 88 million km and 133.7 million km from the Earth. But it approaches the Sun at a speed of 55 km/s, it traverses 4,750,000 km per day, it is in the sky, about 6 times the apparent diameter of the Moon. November 14, its magnitude is about 6 and should theoretically reach a maximum around the -12.5 magnitude (see table matching apparent magnitudes attached). The comet Ison at the end of 2013, is the star of many observations and a variety of telescopes on Earth eagerly await the remarkable shot. However November 16, 2013, the comet Ison is still fairly bright and blue tail is tapered. We can be seen it, in the northern hemisphere in the early morning over the horizon EAST.
Celestial object | Apparent magnitude (max) |
Sun | -26.7 |
Full Moon | -12.6 |
Venus | -4.6 |
Mars | -2.9 |
Sirius (α Canis Majoris) | -1.5 |
Canopus (α Carinae) | -0.7 |
Arcturus (α Bootis) | -0.04 |
Alpha Centori A (α Cen) | -0.01 |
Véga (α Lyrae) | 0 |
Rigel (α Ori) | +0.12 |
Procyon (α Canis Minoris) | +0.38 |
Achernar (α Eridani) | +0.46 |
Betelgeuse (α Ori) | +0.5 |
Hadar (β Cen) | +0.6 |
Capella A (α Ori) | +0.71 |
Altair (α Aql) | +0.77 |
Comet ISON comes closer to the Sun and it certainly will not survive one more day to its close encounter of November 28, 2013, with the Sun whose the diameter is 1,392,000 km.
Imagine this fragile ice ball 1.2 km in diameter, into a burning region of space just 1.17 million km from the Sun, less than a solar diameter. At this distance it is subjected to temperatures of 2700 ° C. It really has no chance to emerge intact, besides the scientific community believes less and less for its survival. Our Sun is an infernal nuclear pot, constantly shaken by huge explosions in space that send massive amounts of matter. This thermonuclear power plant is really monstrous, it produces a huge source of heat every second, energy is 380 billion billion megawatts, which corresponds to 3,800 billion times the power of all our global nuclear reactors. Our Earth, 150 million km, receives about 1000 watts for each square meter of its atmosphere and we can easily imagine that will receive the small comet in the solar furnace only 1 million km. Even its core rock should disappear. In this video the fragile comet can still be seen in the light of the Sun, gradually brightening morning sky. In a few hours the fate of one of the most unusual modern comets will be fixed. Telescopes such as the Canary Islands who took this video, can capture the decay of the comet flowing into the solar fire.
Comet ISON (C/2012 S1) was captured by the SOHO (Solar and Heliospheric Observatory) spacecraft at the precise moment the comet passes perihelion (closest to the Sun), November 28, 2013 at 18:37 UTC.
In this video of the satellite SOHO, the circumference of the Sun is drawn by a white circle and its dazzling crown is hidden, to see the small comet. This sequence between November 26, 11:30 and November 30, 2013 6:00, traces its course, second by second, as it delves into the hell that is the solar corona. This small icy body that flows into this hell, faces the heat of solar radiation at the cost of a considerable loss of weight. It has certainly lost much of its weight from the crown and yet we see ISON speed approaching the Sun and then miraculously out of the furnace (2500 ° C), on the other side of the mask. By carefully observing the trace of the comet, you can see the passage of perihelion, the comet nucleus stretch, suggesting that the core is broken. There appears to be more compact and like debris in sequence along the orbit of comet without dispersing. Over its trace appears stronger when spring behind the mask of the eclipse, as if a fraction of the comet had resisted.
But will it disappear completely?
We have an answer before January 2014, as NASA's STEREO use their cameras to search for all light fragments over the coming weeks. STEREO but will not be the only telescope trained on fragments ISON, the infrared telescope IRTF (Infrared Telescope Facility) NASA in Honolulu, Hawaii, will also use its large 3 meter telescope spectroscopy to analyze the comet. It is likely that radio telescopes around the world will also be able to tell us more about what exactly happened. Hubble and Chandra also go in mid-December 2013, the search for the remains of the comet. Then finally the Spitzer Space Telescope infrared biggest launched by NASA, which has already seen the carbon dioxide emissions from Comet ISON in July 2012, we provide the definitive answer on what remains of the small comet at early 2014.