Комета C/2012 S1 (ISON) (А. Новичонок, В. Невский) -- 2013

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Комета пройдет в поле зрения камер аппаратов Stereo:

Anticipated STEREO observations of Comet ISON

 Comet C/2012 S1 was discovered in September 2012 by Russian astronomers Vitali Nevski and Artyom Novichonok using data from the International Scientific Optical Network (ISON). For that reason, it is also known as Comet ISON. This comet is on a close encounter with the Sun on November 28, 2013 (Thanksgiving day in the U.S.), when it will pass at a distance of only 2.7 solar radii from the center of the Sun. Since Comet ISON was discovered so far out, beyond the orbit of Jupiter, and will pass so close to the Sun, many think that this could turn out to be a major comet. A number of NASA missions, including STEREO, are planning an observing campaign to observe the comet as it passes by the Sun.
 If Comet ISON works out as expected, the STEREO spacecraft should have a spectacular view. The movie below shows the geometry of the STEREO Ahead (red) and Behind (blue) spacecraft during the passage of Comet ISON (orange). The top panel shows the view from above looking down on the orbital plane of the planets (the ecliptic plane), while the bottom panel shows the view from the side. Note that the comet's orbital path is highly inclined to the ecliptic plane. As the comet approaches the Sun, it comes in at a fairly shallow angle, but leaves at a much steeper one, carrying it well above the ecliptic plane. If one only looked at the top-down view, it looks like the comet passes close to the Earth around the end of December, but the view from the side shows that this is not really the case.

 An even better way to examine the orbit of Comet ISON is to use this three-dimensional JAVA orbit tool provided by the STEREO SECCHI team.
 The first STEREO telescope to see Comet ISON will be the large angle Heliospheric Imager #2 on the Ahead spacecraft (HI2-A). The first image below shows the projected day-by-day location of the comet in the HI2-A field-of-view from October 10, 2013, when it is expected to enter on the left side of the field, through November 23, 2013, when it is expected to leave on the right side of the field. Next to this is the comet's passage through the smaller HI1-A field-of-view November 21-28, 2013. Click on each image for a larger version.
 

Predicted day-by-day position of Comet ISON in the HI2-A    field-of-view from October 10, 2013 on the left, to November 23, 2013    on the right.Predicted day-by-day position in the HI1-A field-of-view from    November 21-28, 2013, moving from left to right.
 
 Both STEREO spacecraft will have a view of the comet in the COR1 and COR2 coronagraphs in the hours around closest approach on November 28. This is shown for the Ahead and Behind spacecraft respectively in the images below. Click on each image for an enlarged view. In each case, the comet enters from the lower left and exits near the top of the image. The coronagraphs on STEREO Ahead will be able to see the comet for about a day and half between about 04:00 UT on November 28, and 14:00 UT on November 29. The Behind coronagraphs will have a longer look at the comet, from about 06:00 UT on November 26 until the end of the day on November 29. During the period when Comet ISON is closest to the Sun, it will actually pass in front of the Sun as seen from Behind. This opens up the exciting possibility that we might see extreme-ultraviolet emission from the comet, as was seen recently with the bright sungrazing Comet Lovejoy.



Predicted hour-by-hour position of Comet ISON in the COR2-A    (blue) and COR1-A (green) fields-of-view between 04:00 UT on November 28,    and 14:00 UT on November 29.Predicted hour-by-hour position of Comet ISON in the COR2-B    (blue), COR1-B (green), and EUVI-B (orange) fields-of-view between    06:00 UT on November 26, and 00:00 UT on November 30.
 



Predicted position of Comet ISON in the EUVI-B field-of-view in    ten-minute intervals between 18:10 UT and 20:10 UT on November 28,    2013.
 

 The LASCO C2 and C3 coronagraphs on the Solar and Heliospheric Observatory (SOHO) satellite will also have a view of the comet as it passes through their fields-of-view, as shown below. From SOHO's viewpoint the comet enters from the lower right early on November 27 and exits towards the top near the end of November 30. There's also a possibility that the Solar Dynamics Observatory (SDO) satellite might be able to observe Comet ISON in extreme-ultraviolet when it's closest to the Sun. However, at the currently estimated apparent distance of 1.8 solar radii, SDO would have to point away from the Sun to see the comet.

Спойлер

Predicted hour-by-hour position of Comet ISON in the LASCO C3    (blue) and C2 (red) fields-of-view on SOHO, November 27-30, 2013.    Click on the image for a larger version.
 
 After the comet swings around the Sun, it passes once again through the HI1-A field-of view during the first week in December, as shown below. At this point, the comet is leaving at such a steep angle that the nucleus never passes through the HI2-A field-of-view without rolling the spacecraft, though a tail might be visible.


Predicted day-by-day position of Comet ISON on the outbound    journey in the HI1-A    field-of-view from December 1-7, 2013, moving from right to left.    Click on the image for a larger view.
 

 All the plots on this page are based on preliminary estimates of Comet ISON's orbit. As more observations of the comet are collected, these orbital estimates will be improved over time.

[свернуть]

http://stereo-ssc.nascom.nasa.gov/comet_ison/

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Hubble Captures Comet ISON
04.23.13


NASA's Hubble Space Telescope provides a close-up look of Comet ISON (C/2012 S1), as photographed on April 10, when the comet was slightly closer than Jupiter's orbit at a distance of 386 million miles from the sun. Credit:NASA, ESA, J.-Y. Li (Planetary Science Institute), and the Hubble Comet ISON Imaging Science Team
  › Larger image

 This NASA Hubble Space Telescope image of Comet (C/2012 S1) ISON was photographed on April 10, when the comet was slightly closer than Jupiter's orbit at a distance of 386 million miles from the Sun (394 million miles from Earth).

 Even at that great distance the comet is already active as sunlight warms the surface and causes frozen volatiles to sublimate. A detailed analysis of the dust coma surrounding the solid, icy nucleus reveals a strong, jet blasting dust particles off the sunward-facing side of the comet's nucleus.

 Preliminary measurements from the Hubble images suggest that the nucleus of ISON is no larger than three or four miles across. This is remarkably small considering the high level of activity observed in the comet so far, said researchers. Astronomers are using these images to measure the activity level of this comet and constrain the size of the nucleus, in order to predict the comet's activity when it skims 700,000 miles above the sun's roiling surface on November 28.

 The comet's dusty coma, or head of the comet, is approximately 3,100 miles across, or 1.2 times the width of Australia. A dust tail extends more than 57,000 miles, far beyond Hubble's field of view.

 More careful analysis is currently underway to improve these measurements and to predict the possible outcome of the sungrazing perihelion passage of this comet.

 This image was taken in visible light. The blue false color was added to bring out details in the comet structure.

 ISON stands for International Scientific Optical Network, a group of observatories in ten countries who have organized to detect, monitor, and track objects in space. ISON is managed by the Keldysh Institute of Applied Mathematics, part of the Russian Academy of Sciences.

Space Science Telescope Institute

http://www.nasa.gov/mission_pages/hubble/science/ison-view.html

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"Хаббл" сделал фотоснимки потенциально самой яркой кометы десятилетия

МОСКВА, 24 апр — РИА Новости. Космический телескоп "Хаббл" впервые провел "фотосессию" кометы ISON — потенциально самой яркой кометы десятилетия; обработка снимков показала, что ядро кометы имеет размер около 5-6 километров, а газовая оболочка простирается на 5 тысяч километров, что в 1,2 раза шире Австралии, сообщает НАСА.

Комета C/2012 S1 (ISON) была открыта 21 сентября 2012 года российским астрономом Артемом Новичонком и его коллегой из Белоруссии Виталием Невским на обсерватории в районе Кисловодска, входящей в сеть ISON. Комета в ноябре 2013 года пройдет на расстоянии в 0,012 астрономической единицы (среднего радиуса земной орбиты) от Солнца. В это время яркость кометы может достичь яркости полной Луны, и она, возможно, станет самой яркой в десятилетии.

Как и все кометы, C/2012 S1 (ISON), представляет собой "кусок грязного льда" — смесь водяного льда, замерзших газов и пылевых частиц. При приближении к Солнцу лед начинает испаряться, вокруг ядра появляется газопылевая оболочка — кома, и хвост, который может простираться на миллионы километров, а сама комета становится значительно ярче.

Сейчас комета ISON еще не видна невооруженным глазом — она находится на расстоянии чуть ближе радиуса орбиты Юпитера. Однако на снимках, которые "Хаббл" сделал 10 апреля, видно, что даже на такой дистанции комета довольно активна — выбрасывает пылевые струи (джеты), а ее пылевой хвост тянется на 92 тысячи километров. Предварительные оценки показали, что размер ядра кометы ISON составляет от 4,8 до 6,4 километра, что сравнительно немного — одна из ярчайших в истории комета Хейла-Боппа имела ядро размером в 60 километров, а комета Галлея — 15 на 8 километров. В то же время одна из очень ярких комет — комета Лавджоя, которая в декабре 2011 году сравнилась по яркости с Венерой, имела ядро размером лишь 500 метров.

В течение ближайшей недели специалисты намерены продолжить наблюдения с помощью "Хаббла", чтобы выяснить, в частности, химический состав кометы.

http://ria.ru/science/20130424/934266618.html

[Димитър]

instml пишет:
 Сейчас комета ISON находится на расстоянии чуть ближе радиуса орбиты Юпитера. Однако на снимках, которые "Хаббл" сделал 10 апреля, видно, что даже на такой дистанции комета довольно активна — выбрасывает пылевые струи (джеты), а ее пылевой хвост тянется на 92 тысячи километров.

А пылевые и газовые струи вполне могут отклонить комету и еще неизвестно, на каком расстоянии от Марса она пойдет...

[ronatu]

К Марсу эту другая - Комета C/2013 A1 (Siding Spring)

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Обе они к Марсу, только на разных расстояниях пролетят

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Димитър пишет:

instml пишет:
 Сейчас комета ISON находится на расстоянии чуть ближе радиуса орбиты Юпитера. Однако на снимках, которые "Хаббл" сделал 10 апреля, видно, что даже на такой дистанции комета довольно активна — выбрасывает пылевые струи (джеты), а ее пылевой хвост тянется на 92 тысячи километров.
 http://ria.ru/science/20130424/934266618.html

А пылевые и газовые струи вполне могут отклонить комету и еще неизвестно, на каком расстоянии от Марса она пойдет...

11 млн км

[Димитър]

instml пишет:
Обе они к Марсу, только на разных расстояниях пролетят
эта - 11 млн км

Значит, все таки я правильно ошибся?
       :oops:

[Сергио]

после перигелия комета развалится.

[Димитър]

Если развалится, тогда осколки разлетаются в разные стороны. Точно часть осколков врежется в Марс!

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Через неделю комета пролетит в 11 млн км от Марса!

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Димитър пишет:
Если развалится, тогда осколки разлетаются в разные стороны. Точно часть осколков врежется в Марс!

Нет, Марс до Солнца!

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Текущая оценка яркости кометы: около +12m

[Bizonich]

instml пишет:
Через неделю комета пролетит в 11 млн км от Марса!

Ждем снимков!!!

[LL_]

До 30 сентября этого года, если повезет с погодой или тучки вдруг разойдутся, на аппаратуре ГАИШ любой желающий бесплатно может сам посмотреть на эту комету.

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LL пишет:
До 30 сентября этого года, если повезет с погодой или тучки вдруг разойдутся, на аппаратуре ГАИШ любой желающий бесплатно может сам посмотреть на эту комету.

Из Москвы ни хрена не увидеть, даже при наличии хорошей погоды.

[ZOOR]

http://www.nasa.gov/content/goddard/six-minute-journey-to-study-comet-ison/#.UoTzY_msiSr

A Six-Minute Journey to Study Comet ISON
Nov. 13, 2013


Comet ISON streams through space in this image captured on Oct 9, 2013, by the Hubble Space Telescope. The NASA-funded FORTIS sounding rocket will launch in mid-November to join the dozens of observatories studying the comet.


In an example of an extremely tight turnaround, a NASA-funded team has spent six months preparing for a mid-November launch to observe Comet ISON during a six-minute sounding rocket flight. The Far-ultraviolet Off Rowland-circle Telescope for Imaging and Spectroscopy, or FORTIS, was originally designed – and flew for the first time in May 2013 -- to measure the presence of different atoms in far away galaxies. However, the telescope happens to also be well-tuned to study carbon monoxide, hydrogen, oxygen, and other interesting atoms expected on Come ISON as well, so the team sought funding fr om NASA to quickly launch it again.

"FORTIS took its first flight in May," said Stephan McCandliss, the Fortis Principal Investigator at The Johns Hopkins University in Baltimore, Md. "We knew we were going to rebuild the instrument and fly it again, regardless – it was just a question of how fast. When our proposal to use FORTIS to look at ISON in November was accepted, we started working our tails off."

Catalogued as C/2012 S1, Comet ISON was first spotted 585 million miles away in September 2012 and it is now travelling toward the sun at a whopping 48,000 mph. The comet will make its closest approach to the sun on Nov. 28, 2013. This is the comet's very first trip around the sun. It is thought to be made of pristine matter fr om the earliest days of the solar system's formation, its top layers never having been lost by a trip near the sun. Scientists have been pointing as many ground-based observatories as they can and at least 15 space-based assets towards the comet along the way, in order to learn more about this time capsule fr om when the solar system first formed.


NASA will launch FORTIS on board a two-stage Black Brant IX suborbital sounding rocket to study Comet ISON fr om the White Sands Missile Range, N. M.


FORTIS will be able to look at the molecules and atoms inside the comet by taking advantage of the fact that, as the comet moves toward the sun and warms, its rate of sublimation (a process similar to evaporation in which solid matter transitions directly into gas) increases. FORTIS will observe that gas with an instrument called a spectrograph, which can separate incoming light into its component wavelengths. The intensity of light at each wavelength, in turn, corresponds to the sublimation rate of certain atoms. A series of shutters open and close throughout flight to allow the instrument to gather information from several areas at once: different parts of a galaxy, for example, or in this case different parts of the comet.

"Hubble has an instrument that could look for these same atoms, but Hubble can't look this close to the sun," said McCandliss. "So we are in a really unique situation wh ere we can capture observations of this material coming off the comet at a point wh ere heating from the sun is getting stronger and stronger."

FORTIS will launch from White Sands Missile Range in New Mexico, and will soar up above 60 miles high, wh ere it will be above much of Earth's atmosphere, which would interfere with the detection of cometary emissions at far-ultraviolet wavelengths. FORTIS is flying an autonomous targeting system that will locate the center of the comet on the fly and then deploy a pre-programed array of the instrument's microshutters, in order to observer 43 different locations in the comet. Overall, FORTIS will sample a region approximately 625,000 miles in diameter. This system, designed by former Johns Hopkins University graduate student Brian Fleming, uses a prototype of the microshutter arrays built by NASA's Goddard Space Flight Center in Greenbelt, Md. for the Near Infrared Spectrograph on the James Webb Space Telescope. When the instrument comes back down to the ground, the team will recover it and should be able to use it again down the road.

Such short flights are a signature of NASA's sounding rocket program, which launches inexpensive missions to gather robust science results while providing the chance to build and improve newer scientific instruments. Such flexibility of timing and cost is what allowed the FORTIS team to fly on such a short turnaround after its first flight – which included a bumpy landing leading to some needed repairs.

The window for the FORTIS launch begins on Nov. 19, 2013, just nine days before ISON sling shots around the sun to travel back out into space, unlikely to ever return. Indeed, the comet may not even survive the trip around the sun wh ere it could break up and fizzle out completely. But before that happens, FORTIS will join a world-wide contingent of observatories trying to understand this early bit of our solar system's history.

Karen C. Fox
NASA's Goddard Space Flight Center, Greenbelt, Md.

[vaitek]

В москве/подмосковье вообще без шансов увидеть?

[Александр Ч.]

Блеск на уровне 8-й звездной величины, т.е. невооруженным глазом не видно.

[Сергио]

Александр Ч. пишет:
Блеск на уровне 8-й звездной величины, т.е. невооруженным глазом не видно.

я уже вооружился в честь 25летия ьурана.