American comet finder Alan Hale spent more than 400 hours of observation time searching for new “tailed stars.” And all to no avail. But then, on July 22, 1995, while waiting for the rise of Comet D'Arre, he decided to admire the numerous objects of the Sagittarius constellation. And the incredible happened - a diffuse object 10.5 was discovered not far from M70 magnitude, which was not here before. Alan Hale managed to discover a comet at a time when he was not looking for them!
Half an hour later, the comet was independently found by Thomas Bopp (USA). At the time of discovery, it had a small condensation in the center and a coma measuring about 2 arcminutes. She was also seen to have a small tail mark pointing north.
The first calculation of the comet's orbit was made four days after the discovery. It turned out that during these days she was located more than 6 AU. from the Sun, that is, behind Jupiter, and, nevertheless, already had such a fairly high brilliance. According to the calculated orbit, the comet was found on plates taken back in April 1993 at the Anglo-Australian Observatory. It had a magnitude of 18 m and a coma size of 0.4". Then the comet was separated from the Sun by 13.1 AU.
Soon other old photographs of the comet were discovered, which made it possible to quickly clarify its orbit. It turned out that it orbits in a highly elongated ellipse (eccentricity 0.997), and the orbital period is approximately 4000 years! In any case, a very rare and special “guest” is now flying towards Earth. Indeed, the fairly high brightness of the comet at a distant distance indicates its high absolute brightness. And if you believe the calculations, the comet will pass perihelion on April 1-2, 1997, and during the first four months of 1997 it will attract the attention of not only astronomers, but also all residents northern hemisphere Earth.
Throughout 1996, the comet will move around celestial sphere to the north, while its brightness will increase. In November, the comet will pass through the northern part of the constellation Ophiuchus, near the globular star clusters M10 and M12, and will become visible to the naked eye in the evening hours.
From January 1997, the comet, already very bright (2 m), can be observed both in the evening and in the morning (the comet will rise significantly before the Sun, and come in later). It will cross the constellations Eagle, Chanterelle, Cygnus, and Lizard and enter the Andromeda constellation in March. At this time, its visibility conditions will be the best, and the brightness is predicted to reach -1.7 m!
Thus, the comet will be almost equal in brilliance to Jupiter, and will be second only to the Sun and Moon! (Venus is not visible at this time). The comet will be a magnificent sight, but the residents will see a truly unique sight Eastern Siberia March 9, 1997, during the observation of a total solar eclipse. At the moment of totality, high above the eclipsed Sun and its brilliant corona, Comet Hale-Bopp will appear before observers in all its splendor. Spectacle terrifying and admiration! Screaming astrologers will probably predict at least the end of the world for this day.
We emphasize, however, that the brightness estimates presented here are based on preliminary data. There are indications that the comet experienced an outburst before its discovery. Therefore, it is now quite bright, and its brightness during its approach to the Sun is overestimated. However, it is obvious that this will be the “main” astronomical object of the beginning of 1997.
At the beginning of April 1997, the morning visibility and evening visibility of this beautiful comet will cease at the beginning of May. She will leave the Earth, and if she returns, it will not be very soon.
For those who want to independently calculate the coordinates of the comet, we present the elements of its orbit. Time of passage of perihelion, T per. =1997, March, 31.71081; eccentricity, e=0.9972029; perihelion argument, ω= 130.34251°; longitude sunrise, knot, Ω=282.47093°; orbital inclination, i=88.89915°; perihelion distance, q=0.9180262 a.u.
How it was
Alan Hale: - As a rule, I observe known comets about once a week, making estimates of their brightness. That night was the first after a week and a half bad weather, I planned to observe two comets: Clark and D'Arre. After determining the brightness of Comet Clark, I had more than an hour to wait for Comet D'Arre to rise to a sufficient height above the horizon. There was nothing to do and I decided to admire the deep sky objects in the constellation Sagittarius. Looking through the telescope at M70, I immediately discovered an object in my field of view that had never been there...
Thomas Bopp: - On the evening of July 22, my friends and I went out of town in search of a darker place for observations. My friend Jim Stevens took a 45cm Dobson with him. After observing several objects in Swan, Jim suggested, "Let's take a look globular clusters in Sagittarius." After M22 and M28, we pointed the telescope at the M70 cluster. Jim went to get a map to select the next object, and I continued to admire M70, shaking the telescope tube back and forth a little. And then I noticed a diffuse object. Attempts to identify it was not successful according to the atlas. In addition, the object discovered its movement relative to the stars...
Comet Hale-Bopp (C/1995 O1) belongs to the class long-period comets. It is one of the most popular sights of the 20th century. The comet is also one of the brightest in the last few decades. The discoverers are two independent amateur astronomers, namely Alan Hale and Tom Bopp. The discovery occurred on July 23, 1995, at that moment Hale was at home and looking at evening sky through his telescope, then he noticed a strange blurry point among the stars. Bopp was spending time with friends in the Arizona desert, one of them brought a homemade telescope to the meeting, and suddenly a bright spot flashed in the eyepiece. After checking with the ephemeris of all known at that time space objects, Bopp concluded that he had found something new. Then he simply sent a telegram to the same place as Hale.
Interestingly, the comet was found at a great distance from Earth, 7.2 AU. This made it possible to put forward the assumption that when approaching the Earth it would be clearly visible in the sky. Also, C/1995 O1 could be observed with the naked eye for record long periods, namely, more than 18 months, anyone could see this space object. At the same time, the comet caused some confusion among people, as rumors began to actively spread that there was a UFO in its tail. They also became the main cause of mass suicides committed by followers of the “Gates of Heaven” movement.
As the comet approached the Sun, astronomers began to actively study the materials from which it consisted. Managed to do several important discoveries. The most important of these was the observation of the third type of tail. Typically, such objects have only two tails - ion and dust, but in this case there was a third - sodium, which astronomers were able to notice only by using a complex system of filters and special optics. Sodium streams have been found in other comets, but they never created a tail. IN in this case the sodium tail was made of neutral atoms and extended over 50 million km.
The main source of sodium was located inside the comet, but not in the nucleus. There are known theories according to which such a source can form, for example, it could be collisions of dust particles, or sodium is “squeezed out” from particles under the influence of ultraviolet rays. However, it is not yet known exactly how this tail was created. In addition, scientists have found that the comet contains the following substances:
Also in 1999, disputes arose between researchers that the comet could have two nuclei at once. According to this theory, the secondary core has a diameter of about 30 km, while the main one is 70 km, while there was more than 180 km of empty space between the cores, and mutual circulation takes three days. Given that the results of this assumption were based purely on theoretical knowledge, the theory about the second nucleus was subject to a barrage of criticism from practicing astronomers, since their equipment could not detect it. Previously observed comets that had two nuclei were extremely unstable and quickly disintegrated under the influence of the gravity of neighboring stars or planets.
Already in May 1996, the comet could be seen with the naked eye, although the increase in brightness became slower closer to the second half of the year. Scientists still suggested that it would become one of the brightest. On March 23, the comet passed at a minimum distance from, only 196.7 million km. Perihelion arrived on April 1, becoming a real spectacle for all observers. The comet shone brighter than all the stars except Sirius, and it could be seen closer to evening.
The next perihelion will not come soon, since it takes about 2,400 years for the comet to pass through its orbit.
Conclusion
Comet Hale-Bopp is unique phenomenon, which humanity will not soon forget. Thanks to active work The media and some sites on the Internet learned about the comet great amount of people. In terms of popularity, it was able to surpass Halley's comet and broke several records at once: in detection range, nucleus size and brightness. It was observed approximately 2 times longer than the previous object of this type. IN total, the discovery of this comet allowed us to make several important discoveries that allowed us to better understand the mechanisms by which the Cosmos functions.
And one of the brightest in several last decades. Was visible naked eye the record duration is 18 months, twice the previous record set by the Great Comet of 1811.
Opening
The comet was discovered independently by two American observers, Alan Hale and Thomas Bopp. Hale had spent many hundreds of fruitless hours searching for comets, and near his home in New Mexico he was observing known comets when, around midnight, he suddenly encountered a nebulous object measuring 10.5 m near the globular star cluster M70 in the constellation Sagittarius. Hale first determined that there were no other deep space objects near this cluster. Next, he discovered that the object was moving noticeably against the background of stars (and therefore was in the solar system), and wrote email to the Central Bureau of Astronomical Telegrams, which tracks astronomical discoveries.
Bopp did not have his own telescope. He was out with his friends near Stanfield, Arizona, observing star clusters and galaxies when a speck of light flashed before his eyes through the eyepiece of his friend's telescope. Checking the ephemeris famous objects solar system, Bopp realized that this speck was a new object, and sent a telegram to the same place as Hale.
The next morning, the discovery of a new comet was confirmed, which was given the name Comet Hale-Bopp and the designation C/1995 O1. The discovery was announced in Circular No. 6187 of the International Astronomical Union. At the time of discovery, the comet was at a distance of 7.1 AU. e. from the Sun.
The formation of the "Great Comet"
Approaching the Sun, comet Hale-Bopp became brighter: in February it reached 2nd magnitude, and one could already distinguish its tails - bluish ion tails directed in the direction opposite to the Sun, and yellowish dust tails curved along the comet's orbit. A solar eclipse in Eastern Siberia and Mongolia on March 9 made it possible to see the comet during the day. On March 23, 1997, comet Hale-Bopp approached the Earth at a minimum distance of 1.315 AU. e. (196.7 million km).
At perihelion on April 1, 1997, the comet presented a stunning spectacle. Co average size−0.7 it shone brighter than any star (excluding Sirius), and its two tails stretched across the sky by 15-20 degrees (and their parts invisible to a simple observer - by 30-40 degrees). The comet could be observed just after dusk; and although many “large” comets, passing perihelion, were close to the Sun, Comet Hale-Bopp could be observed in the northern hemisphere all night.
Comet Hale-Bopp could be even more impressive. If it approached the Earth at the same distance as comet Hyakutake in 1996 (0.1 AU), it would exceed Venus in brightness, reaching −5th magnitude.
Comet removal
After passing perihelion, the comet moved to the southern celestial hemisphere, and its brightness began to weaken. The comet looked much less impressive to southern observers, but they were able to see its brightness gradually decrease throughout the second half of 1997. The last known observation of the comet with the naked eye was in December 1997, meaning it was visible for about 18 and a half months. This time frame broke the previous record of 9 months, set by the Great Comet of 1811.
Now Comet Hale-Bopp is moving away, and its brightness continues to decrease. In August 2004, it flew beyond the orbit of Uranus, and as of mid-2008 it was located at a distance of about 26.8 AU. e. from the Sun. However, it is still being tracked by astronomers. The reason for this is the unusually long activity of the comet. Recent observations (October) indicate that the comet still has a coma with a brightness of about 20 m. It is assumed that the reason for the unusually long activity lies in the slow cooling of the giant comet nucleus.
It is expected that the comet will be observable with large telescopes until about 2020, until its brightness drops to 30 m. The comet will return to Earth around 4390. It is estimated that in one of its next returns, Comet Hale-Bopp has a 15% chance of becoming circumsolar, and serving as the progenitor of a new family, such as the Kreutz family of comets.
Orbital changes
Scientific research
As the comet approached the Sun, it was intensively studied by astronomers. In doing so, some important and interesting discoveries were made.
One of the most significant results was the discovery of a third type of tail on the comet. In addition to the usual gas (ion) and dust tails, there was also a weak sodium tail, visible only with the help of powerful tools And complex system filters Sodium streams have previously been noticed in other comets, but in none of them did they form a tail. At comet Hale-Bopp, it consisted of neutral atoms and stretched almost 50 million kilometers in length.
Excess deuterium
The comet was found to contain high levels of deuterium in the form of heavy water: almost twice as much as found in Earth's oceans. This means that while comet impacts with Earth could be an important source of water on the planet, they could not be the only source (unless, of course, such a concentration is typical for all comets).
The presence of deuterium in other hydrogen compounds was also discovered. The ratio of these elements varied in different structures, so astronomers suggested that the comet's ices formed not in a protoplanetary disk, but in an interstellar cloud. Theoretical models ice formations in nebulae show that comet Hale-Bopp formed at a temperature of 25-45.
Organic compounds
Observations of comet Hale–Bopp using a spectroscope revealed the presence of a group of organic compounds, some of which had never been found in comets. These complex molecules, such as acetic and formic acids and acetonitrile, could be part of the core or obtained during chemical reactions.
Argon detection
Comet Hale-Bopp was also the first comet to contain the noble gas argon. Noble gases chemically inert and extremely volatile, and different gases have different boiling points. The latter property helps when tracking temperature changes cometary ices. Thus, krypton evaporates at a temperature of 116-120 K, and it was found that its content in the comet is 25 times lower than in the sun; on the contrary, the sublimation temperature of argon is 35-40 K, and its content is higher than that of the sun.
It was found that the temperature inland ice comets Hale-Bopp never exceeded 40 K, and at the same time at some point their temperature was above 20 K. Unless the formation of the Solar system occurred at temperatures lower than currently assumed, and at a higher initial content of argon, then the presence of argon in the comet means that Comet Hale-Bopp formed beyond the orbit of Neptune somewhere in the Kuiper belt, and then moved to the Oort cloud.
Rotation
Ejection of matter from the comet's nucleus.
The comet's activity and gas emissions were not equally distributed over the entire surface of the nucleus, but manifested themselves in the form of strong emissions from certain points. From observations of them, it became possible to calculate the rotation period of the comet's nucleus. It was found that the nucleus of Comet Hale-Bopp actually rotates, but at different times different meanings period: from 11 hours 20 minutes up to 12 hours 5 minutes The superposition of rotations with several periods suggests that the comet's nucleus had more than one axis of rotation.
Another period (called the “super period”), calculated from dust emissions from the surface, turned out to be equal to 22 days. And in March 1997, it suddenly became clear that between February and March the comet changed its direction of rotation to the opposite. The exact reasons for this behavior remain a mystery, although it seems that it was due to strong non-periodic gas emissions.
Sputnik controversy
In 1999, a work appeared, the author of which was for full explanation The observed nature of the dust emission suggested the presence of a double nucleus in the comet. The work was based on theoretical research and did not refer to any direct observations of the secondary nucleus. It was stated, however, that it should have a diameter of 30 km, with a main core of 70 km, a distance between them of 180 km, and a period of mutual circulation of 3 days.
The provisions of this work were disputed by practicing astronomers, who argued that even high-resolution images of the comet taken by the Hubble telescope did not contain traces of the double nucleus. In addition, in previously observed cases of comets with double nuclei, they did not remain stable for long: the orbit of the secondary nucleus was easily disrupted by the gravity of the Sun and planets, tearing the comet apart.
A few months later, in March 1997, religious cult, who called himself "Gates of Heaven" ("Heaven's Gate"), chose the appearance of a comet as a signal for mass cult suicide. They stated that they were leaving their earthly bodies to travel to a ship following the comet. 39 cult followers committed suicide at Rancho Santa Fe (English)Russian.
Legacy of the Comet
Notes
- Nakano, S. NK 1553 - C/1995 O1 (Hale-Bopp)(English) . OAA computing section circular (February 12, 2008). Retrieved November 10, 2008. Archived August 20, 2011.
- Calculated from the value of future 1/a (undefined) . OAA computing section circular NK 1553. Retrieved December 27, 2015.
- Kidger, M. R.; Hurst, G; James, N. The visual light curve of comet C/1995 O1 (Hale-Bopp), from discovery to the end of 1997 = The Visual Light Curve Of C/1995 O1 (Hale-Bopp) From Discovery To Late 1997 // Earth, Moon, and Planets . - 2004. - T. 78, issue. 1-3. - pp. 169-177.- DOI : 10.1023/A:1006228113533
- IAU Circular 6187: 1995 O1(English) (inaccessible link - story) . International Astronomical Union (23 July 1995). Retrieved November 10, 2008.
- Lemonick, Michael D. Comet of the decade. Part II, Time magazine (March 17, 1997). Retrieved November 8, 2008.
- Thomas Bopp. Amateur Contributions in the study of Comet Hale-Bopp // Earth, Moon, and Planets. - 1997. - T. 79, issue. 1-3. - pp. 307-308.
- Kronk, Gary W. Comet C/1995 O1 (Hale-Bopp)(English) . cometography.com. Retrieved November 10, 2008. Archived August 20, 2011.
- Browne, Malcolm R. Comet Holds Clues to Birth of Time, The New York Times (9 March 1997). Retrieved November 8, 2008.
- Seiichi Yoshida. Light curve of comet C/1995 O1 (Hale-Bopp)(English) (December 20, 2007). Retrieved November 10, 2008. Archived August 20, 2011.
- McGee, H. W.; Poitevin, P. Total solar eclipse March 9, 1997 = The total solar eclipse of 1997 March 9 // Journal of the British Astronomical Association. - 1997. - T. 107, issue. 3. - pp. 112-113.
- Ephemeris generator HORIZONS(English) . JPL. Retrieved November 10, 2008. Archived August 20, 2011.
- The Trail of Hale-Bopp(English) . Scientific American (March 31, 1997). Retrieved November 8, 2008. Archived August 20, 2011.
- Szabó, Gy. M.; Kiss, L. L.; Sárneczky, K. Comet activity at a distance of 25.7 AU. e.: comet Hale-Bopp 11 years after perihelion = Cometary Activity at 25.7 AU: Hale-Bopp 11 Years after Perihelion // The Astrophysical Journal. - 2008. - T. 677, issue. 2. - S. L121-L124.- DOI: 10.1086/588095. - arXiv:0803.1505.
- Gnedin Yu. N. Astronomical observations of the comet of the century. - Decree. ed.
- West, Richard M. Comet Hale-Bopp(English) . European Southern Observatory (7 February 1997). Retrieved November 8, 2008. Archived August 20, 2011.
- Bailey, M. E.; Emel'yanenko, V. V.; Hahn, G.; et al. Evolution of the orbit of Comet Hale-Bopp = Oribital evolution of Comet 1995 O1 Hale-Bopp // Monthly Notices of the Royal Astronomical Society. - 1996. - T. 281, issue. 3. - pp. 916-924.
- Yeomans, Don. Comet Hale-Bopp Orbit and Ephemeris Information(English) . NASA/JPL (April 10, 1997). Retrieved November 8, 2008. Archived August 20, 2011.
- Cremonese, G.; Boehnhardt, H.; Crovisier J.; et al. Neutral Sodium from Comet Hale-Bopp: A Third Type of Tail // The Astrophysical Journal Letters. - 1997. - T. 490. - S. L199-L202.- DOI: 10.1086/311040
- Meier, Roland; Owen, Tobias C. Cometary Deuterium // Space Science Reviews. - 1999. - T. 90, issue. 1-2. - pp. 33-43.- DOI: 10.1023/A:1005269208310
- Rodgers, S. D.; Charnley, S. B. Organic synthesis in the coma of Comet Hale–Bopp? // Monthly Notices of the Royal Astronomical Society. - 2002. - T. 320, issue. 4 . - S. L61-L64. -
The most remarkable discovery was the discovery of a comet in the head large quantity new molecules that have not previously been discovered in other comets. This happened thanks to the spectra high resolution, obtained by observers at large telescopes. B provides a list of all molecules found in the head of Comet Hale-Bopp; Those molecules that were discovered in comets for the first time are underlined. An analysis of the molecular composition of the comet's head allows us to conclude that it contains almost all the molecules that make up the large molecular clouds of our Galaxy, in which, according to current ideas, intense star birth occurs. This confirms the point of view of most astronomers, for which for a long time there was no necessary experimental evidence that comets are the remnants of the circumstellar matter from which our Sun and all the planets were born.
Other characteristic feature Comet Hale-Bopp is the unusually high productivity of molecules in the head of the comet, that is, the number of molecules that escape from the surface of the nucleus in one second. It can be said that even long distances from the Sun (7 AU), the productivity of the main cometary molecules (H 2 O, OH, CH 4, CO 2, NH 3, CN, C 2) in the head of Comet Hale-Bopp was significantly higher than that of any comet on any distance over the past 20 years, when intensive photometric and spectroscopic observations of comets began. The performance values of the main molecules in the head of comet Hale-Bopp at various distances from the Sun are presented.
Finally, the third feature of our comet of the century is its surprisingly strong dustiness.
ps/I personally observed this comet, it was visible even during the day, I wonder how the inhabitants of the whole world missed a comet the size of the Earth that crashed into the Sun, even if a comet 45 km in diameter was visible for 18 months?
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Entry: Comet Hale-Bopp: 18 months in the sky
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Tailed guest over the Valparola pass
Heila Boppa is one of those comets that appear above the Earth once every 2,500 years, and was discovered at the moment when it was already very close to the Earth.
History of Hale Bopp's discovery
It happened on July 23, 1995, when American astronomers named Alan Hale and Thomas Bopp at the same time noticed a very close celestial object moving relative to the stars.
Astronomers decided to report this to the American Central Bureau of Astronomy. It is this that decides whether something new has been discovered. heavenly body. The message was immediately sent, and already on July 24 the whole planet learned about the discovery of a new comet. It bears its name in honor of the discoverers Alan Hale and Thomas Bopp.
The comet they discovered appeared above the Earth in the spring of 1996, or rather in May, and it was possible to see it without special instruments until the winter of 1997; only in December did it leave the horizon of planet Earth. Heila Boppa was and to this day remains the brightest of all that have been observed by scientists. Using complex calculations, they found out that it would be possible to see it next time only in 4390.
Alien device? Or incredible abilities?
Heila - Boppa C/1995 O1
Comet Hale Bopp has been studied by various scientists for a year and a half, as a result of which many discoveries were made, some of which caused a number of heated debates and versions. Among other things, this comet had a tail of the third type, unique in its composition. Usually the tail consists of a gas and dust tail, but this time there was also a sodium tail, which scientists discovered using special complex technical instruments. How neutral atoms were able to form a tail remains a mystery.
Also, this comet had unique properties of its nucleus; when rotating, it changed not only the axis of rotation and period, but even the direction of rotation. As a result, scientists made the assumption that it has two cores, but they could not prove this, nor could they refute it. There was another theory, some researchers suggested that there could be an alien device inside the comet, but no one could prove it.
Signal for self-improvement
Undoubtedly, the comet will go down in history as the most unique celestial body that people were able to observe in the 20th century, as well as the cause of mass crazes on the mystical and apocalyptic wave. All possible legends, myths and strange stories associated with a comet. But the story didn’t end with stories alone.
A sect called “Heaven's Gate,” led by Marshall Applewhite, numbering 39 people, said goodbye to their lives, believing in his teachings. The mentor urged them to undergo a self-improvement program, after which the followers of his sect would leave their bodies and join the aliens. And the widely publicized legend about what exactly alien ship hidden behind a comet and became a signal for sect members. As a result, on March 22, 1997, the most mass case suicide in US history.
