[Vo]:Is a Comet on a Collision Course with Mars?
http://www.universetoday.com/100298/is-a-comet-on-a-collision-course-with-mars/ There is an outside chance that a newly discovered comet might be on a collision course with Mars. Astronomers are still determining the trajectory of the comet, named C/2013 A1 (Siding Spring), but at the very least, it is going to come fairly close to the Red Planet in October of 2014. “Even if it doesn’t impact it will look pretty good from Earth, and spectacular from Mars,” wrote Australian amateur astronomer Ian Musgravehttp://astroblogger.blogspot.com/, “probably a magnitude -4 comet as seen from Mars’s surface.” The comet was discovered in the beginning of 2013 by comet-hunter Robert McNaught at the Siding Spring Observatory in New South Wales, Australia. According to a discussion on the IceInSpace amateur astronomy forumhttp://www.iceinspace.com.au/forum/showthread.php?p=950710 when the discovery was initially made, astronomers at the Catalina Sky Survey in Arizona looked back over their observations to find “prerecovery” images of the comet dating back to Dec. 8, 2012. These observations placed the orbital trajectory of comet C/2013 A1 right through Mars orbit on Oct. 19, 2014. However, now after 74 days of observations, comet specialist Leonid Eleninhttp://spaceobs.org/en/tag/c2013-a1-siding-spring/ notes that current calculations put the closest approach of the comet at a distance of 109,200 km, or 0.00073 AU from Mars in October 2014. That close pass has many wondering if any of the Mars orbiters might be able to acquire high-resolution images of the comet as is passes by. But as Ian O’Neill from Discovery Spacehttp://news.discovery.com/space/astronomy/could-a-comet-hit-mars-in-2014-130225.htm points out, since the comet has only been observed for 74 days (so far), so it’s difficult for astronomers to forecast the comet’s precise location in 20 months time. “Comet C/2013 A1 may fly past at a very safe distance of 0.008 AU (650,000 miles),” Ian wrote, “but to the other extreme, its orbital pass could put Mars directly in its path. At time of Mars close approach (or impact), the comet will be barreling along at a breakneck speed of 35 miles per second (126,000 miles per hour).” Elenin said that since C/2013 A1 is a hyperbolic comet and moves in a retrograde orbit, its velocity with respect to the planet will be very high, approximately 56 km/s. “With the current estimate of the absolute magnitude of the nucleus M2 = 10.3, which might indicate the diameter up to 50 km, the energy of impact might reach the equivalent of staggering 2×10¹º megatons!” An impact of this magnitude would leave a crater 500 km across and 2 km deep, Elenin said. [image: Fragments of Shoemaker-Levy 9 on approach to Jupiter (NASA/HST)]http://ut-images.s3.amazonaws.com/wp-content/uploads/2008/12/shoemaker-levy_9_on_1994-05-17.png Fragments of Shoemaker-Levy 9 on approach to Jupiter (NASA/HST) While the massive Comet Shoemaker–Levy 9 (15 km in diameter) that crashed into Jupiter in 1994 was spectacular as seen from Earth orbit by the Hubble Space Telescope, an event like C/2013 A1 slamming into Mars would be off the charts. Read more: http://www.universetoday.com/100298/is-a-comet-on-a-collision-course-with-mars/#ixzz2M8XbWdrA
Re: [Vo]:Is a Comet on a Collision Course with Mars?
Just getting whacked by the either the ion tail or the dust/debris tail could be a terrible event. One of the twenty or so Shoemaker-Levy 9 nuclei left a dark spot on Jupiter the size of the Pacific Ocean. On Wed, Feb 27, 2013 at 4:21 PM, Mark Gibbs mgi...@gibbs.com wrote: http://www.universetoday.com/100298/is-a-comet-on-a-collision-course-with-mars/ There is an outside chance that a newly discovered comet might be on a collision course with Mars. Astronomers are still determining the trajectory of the comet, named C/2013 A1 (Siding Spring), but at the very least, it is going to come fairly close to the Red Planet in October of 2014. “Even if it doesn’t impact it will look pretty good from Earth, and spectacular from Mars,” wrote Australian amateur astronomer Ian Musgravehttp://astroblogger.blogspot.com/, “probably a magnitude -4 comet as seen from Mars’s surface.” The comet was discovered in the beginning of 2013 by comet-hunter Robert McNaught at the Siding Spring Observatory in New South Wales, Australia. According to a discussion on the IceInSpace amateur astronomy forumhttp://www.iceinspace.com.au/forum/showthread.php?p=950710 when the discovery was initially made, astronomers at the Catalina Sky Survey in Arizona looked back over their observations to find “prerecovery” images of the comet dating back to Dec. 8, 2012. These observations placed the orbital trajectory of comet C/2013 A1 right through Mars orbit on Oct. 19, 2014. However, now after 74 days of observations, comet specialist Leonid Eleninhttp://spaceobs.org/en/tag/c2013-a1-siding-spring/ notes that current calculations put the closest approach of the comet at a distance of 109,200 km, or 0.00073 AU from Mars in October 2014. That close pass has many wondering if any of the Mars orbiters might be able to acquire high-resolution images of the comet as is passes by. But as Ian O’Neill from Discovery Spacehttp://news.discovery.com/space/astronomy/could-a-comet-hit-mars-in-2014-130225.htm points out, since the comet has only been observed for 74 days (so far), so it’s difficult for astronomers to forecast the comet’s precise location in 20 months time. “Comet C/2013 A1 may fly past at a very safe distance of 0.008 AU (650,000 miles),” Ian wrote, “but to the other extreme, its orbital pass could put Mars directly in its path. At time of Mars close approach (or impact), the comet will be barreling along at a breakneck speed of 35 miles per second (126,000 miles per hour).” Elenin said that since C/2013 A1 is a hyperbolic comet and moves in a retrograde orbit, its velocity with respect to the planet will be very high, approximately 56 km/s. “With the current estimate of the absolute magnitude of the nucleus M2 = 10.3, which might indicate the diameter up to 50 km, the energy of impact might reach the equivalent of staggering 2×10¹º megatons!” An impact of this magnitude would leave a crater 500 km across and 2 km deep, Elenin said. [image: Fragments of Shoemaker-Levy 9 on approach to Jupiter (NASA/HST)]http://ut-images.s3.amazonaws.com/wp-content/uploads/2008/12/shoemaker-levy_9_on_1994-05-17.png Fragments of Shoemaker-Levy 9 on approach to Jupiter (NASA/HST) While the massive Comet Shoemaker–Levy 9 (15 km in diameter) that crashed into Jupiter in 1994 was spectacular as seen from Earth orbit by the Hubble Space Telescope, an event like C/2013 A1 slamming into Mars would be off the charts. Read more: http://www.universetoday.com/100298/is-a-comet-on-a-collision-course-with-mars/#ixzz2M8XbWdrA
Re: [Vo]:Is a Comet on a Collision Course with Mars?
ChemE Stewart cheme...@gmail.com wrote: Just getting whacked by the either the ion tail or the dust/debris tail could be a terrible event. I do not think so. I have heard that the tail of a comet is practically a vacuum. The whole volume of earth has only grams of mass. So, a miss is just a miss. The fundamental things apply. (Newtonian physics). One of the twenty or so Shoemaker-Levy 9 nuclei left a dark spot on Jupiter the size of the Pacific Ocean. The nucleus has all the mass. The UniverseToday article confirms that the energy release is estimated at 2*10E10 MT. (20 billion MT). - Jed
Re: [Vo]:Is a Comet on a Collision Course with Mars?
It really depends upon what you read and who you believe. Personally, I do not want to pass through one at close range. A comet has two or more tails, a dust tail and ion tails. The ion tail is gas and ionized or charged particles. As a result of outgassing, comets leave a trail of solid debris. If the comet's path crosses Earth's path, then at that point there are likely to be meteor showers http://en.wikipedia.org/wiki/Meteor_shower as Earth passes through the trail of debris. The Perseid meteor showerhttp://en.wikipedia.org/wiki/Perseids, for example, occurs every year between August 9 and August 13, when Earth passes through the orbit of Comet Swift–Tuttlehttp://en.wikipedia.org/wiki/Comet_Swift%E2%80%93Tuttle .[36] http://en.wikipedia.org/wiki/Comet#cite_note-showers-36 Halley's comet http://en.wikipedia.org/wiki/Halley%27s_comet is the source of the Orionid shower http://en.wikipedia.org/wiki/Orionids in October.[36]http://en.wikipedia.org/wiki/Comet#cite_note-showers-36 We do not even come very close to Swift-Tutle and it triggers meteor showers. Comets were found to emit X-rays http://en.wikipedia.org/wiki/X-rays in 1996.[14] http://en.wikipedia.org/wiki/Comet_tail#cite_note-14 This surprised researchers, because X-ray emission is usually associated with very high-temperature bodieshttp://en.wikipedia.org/wiki/Black_body_radiation. The X-rays are thought to be generated by the interaction between comets and the solar wind: when highly charged ionshttp://en.wikipedia.org/wiki/Ions fly through a cometary atmosphere, they collide with cometary atoms and molecules, ripping of one or more electrons from the comet. This ripping off leads to the emission of X-rays and far ultraviolethttp://en.wikipedia.org/wiki/Far_ultraviolet photons http://en.wikipedia.org/wiki/Photon.[15]http://en.wikipedia.org/wiki/Comet_tail#cite_note-15 I think you are right about the vacuum, vacuum energy that is, from comet nuclei. Stewart On Wed, Feb 27, 2013 at 4:42 PM, Jed Rothwell jedrothw...@gmail.com wrote: ChemE Stewart cheme...@gmail.com wrote: Just getting whacked by the either the ion tail or the dust/debris tail could be a terrible event. I do not think so. I have heard that the tail of a comet is practically a vacuum. The whole volume of earth has only grams of mass. So, a miss is just a miss. The fundamental things apply. (Newtonian physics). One of the twenty or so Shoemaker-Levy 9 nuclei left a dark spot on Jupiter the size of the Pacific Ocean. The nucleus has all the mass. The UniverseToday article confirms that the energy release is estimated at 2*10E10 MT. (20 billion MT). - Jed
Re: [Vo]:Is a Comet on a Collision Course with Mars?
On Wed, Feb 27, 2013 at 3:42 PM, Jed Rothwell jedrothw...@gmail.com wrote:
The UniverseToday article confirms that the energy release is estimated at
2*10E10 MT. (20 billion MT).
An interesting factoid:
This collision would be visible in the daylight sky:
(20e15ton_explosive/s)/(4*pi*(60e6km)^2)?W/m^2
([2E16 * ton_explosive] / second) / ([4 * pi] * [{6E7 * (kilo*meter)}^2]) ?
watt
/ (meter^2)
= 1849.7341 W/m^2
If this collision happened on the moon, it would be an extinction event on
Earth just from the fires it would set from radiant heat:
(20e15ton_explosive/s)/(4*pi*(.25e6mi)^2)?W/m^2
([2E16 * ton_explosive] / second) / ([4 * pi] * [{25 * mile}^2]) ? watt
/ (meter^2)
= 4.1137134E7 W/m^2
RE: [Vo]:Is a Comet on a Collision Course with Mars?
Hey... an icy comet, colliding with and ... whoa, you guessed it, reviving Mars by bringing in lots of water ... sounds like Sci-Fi and for good reason. This would be a much better ending than the original version ... Total Recall, that is - where Mars was brought back to life by some kind of lost alien reactor. Kinda lame... from a technical POV. For those who saw the 2012 version but may not have seen the 1990 cult classic (adaptation of Philip K. Dick's We'll Remember It For You Wholesale ) ... the ending was a let-down, and almost ruined the film. There were parts of the second version which were an improvement over the first, however, so maybe the next time around, sometime around 2020 they will get it all together with a comet ... which will have been predicted by the mutant prophet Kuato, of course. Too bad Phil will not be sharing in the fun ... unless maybe he hangs out at the turbinium mine these days... From: mark.gi...@gmail.com http://www.universetoday.com/100298/is-a-comet-on-a-collision-course-with-ma rs/ There is an outside chance that a newly discovered comet might be on a collision course with Mars. attachment: winmail.dat
Re: [Vo]:Is a Comet on a Collision Course with Mars?
Mars lost its magnetic field and atmosphere a long time ago, maybe it will get its mojo back On Wednesday, February 27, 2013, Jones Beene wrote: Hey... an icy comet, colliding with and ... whoa, you guessed it, reviving Mars by bringing in lots of water ... sounds like Sci-Fi and for good reason. This would be a much better ending than the original version ... Total Recall, that is - where Mars was brought back to life by some kind of lost alien reactor. Kinda lame... from a technical POV. For those who saw the 2012 version but may not have seen the 1990 cult classic (adaptation of Philip K. Dick's We'll Remember It For You Wholesale ) ... the ending was a let-down, and almost ruined the film. There were parts of the second version which were an improvement over the first, however, so maybe the next time around, sometime around 2020 they will get it all together with a comet ... which will have been predicted by the mutant prophet Kuato, of course. Too bad Phil will not be sharing in the fun ... unless maybe he hangs out at the turbinium mine these days... From: mark.gi...@gmail.com javascript:; http://www.universetoday.com/100298/is-a-comet-on-a-collision-course-with-ma rs/ There is an outside chance that a newly discovered comet might be on a collision course with Mars.
[Vo]:Is a Comet on a Collision Course with Mars?
(Sing to the tune As Time Goes By)
And so, it's come to this
A miss is just a miss
When a comet's passing by
The fundamental laws apply
Across the sky ...
[mg]
On Wed, Feb 27, 2013 at 1:42 PM, Jed Rothwell
jedrothw...@gmail.comjavascript:_e({}, 'cvml',
'jedrothw...@gmail.com');
wrote:
So, a miss is just a miss. The fundamental things apply. (Newtonian
physics).
Re: [Vo]:Is a Comet on a Collision Course with Mars?
Which includes quantum mechanics A comet is unpredictable like a cat. Schrödinger's cat with a tail On Wednesday, February 27, 2013, Mark Gibbs wrote: (Sing to the tune As Time Goes By) And so, it's come to this A miss is just a miss When a comet's passing by The fundamental laws apply Across the sky ... [mg] On Wed, Feb 27, 2013 at 1:42 PM, Jed Rothwell jedrothw...@gmail.comwrote: So, a miss is just a miss. The fundamental things apply. (Newtonian physics).
