Astronomers monitoring 埃琳宁彗星have noticed the 彗星 has decreased in brightness the past week, and the coma is now elongating and diffusing. Some astronomers predict the 彗星 will disintegrate and not survive perihelion, its closest approach to the Sun.
On August 19, a massive solar flare and coronal mass ejection hit the 彗星, which may have been the beginning of the end for the much ballyhooed lump of ice and dirt.
澳大利亚业余天文学家伊恩·穆斯格雷夫（Ian Musgrave）说：“我们一直在STEREO航天器图像中追踪它，许多业余爱好者也在他们的望远镜中追踪它。” 天文博客网站。 “Shortly after the coronal mass ejection the 彗星 flared up and you could see some beautiful details in the tail, with the tail was twisting about in the solar wind. But shortly after that Earth- bound amateurs reported a huge decrease in the intensity of the 彗星. We think it may presage a falling apart of the 彗星.”
“It really has been a beautiful little 彗星 and it deserves a better fate than to be overhyped 通过 doom-sayers,” said Musgrave.
Elenin is a long period 彗星 originating from the outer edges of our solar system, and Musgrave noted that 彗星s coming from the Oort cloud which are making their first pass through the solar system tend to be under-performers in terms of brightness. “They don’t brighten as quickly as 彗星s that come around more than once,” he said, “and in looking at the relationship between the brightness and the distance from the Sun, we find empirically that 彗星s that brighten on roughly the same speed as Elenin tend to be likely to fall apart at perihelion.”
However, Musgrave added, each 彗星 is unique. “Some 彗星s will survive and some won’t. The fact that this 彗星 decreased in brightness after the CME, possibly indicates that the 彗星 will not survive. Another possibility is that merely the CME wiped away the coma — the bright cloud of particles around the 彗星 — and the volatiles of the 彗星 might take awhile to come back and recreate the coma, if it does survive.”
Another Australian amateur Michael Mattiazzo has been taking images of the 彗星 (看到他的网站，南方彗星) and he has noticed that the nucleus appears to be elongating. When that occurs, usually the 彗星 disintegrates or splits apart. Above is an animation Mattiazzo created from images he took of 埃琳宁彗星on August 19, 22, 23, 27 & 29.
You can see a wide-field view of the 彗星 通过 astrophotographer Rob Kaufmanns, comparing the view from August 19, 23 and 26 在此链接.
A similar process took place just a few weeks ago with another 彗星, 213P Van Ness.
Do 彗星s break apart often?
“You don’t see it it that often, but it happens surprisingly more than people think,” Musgrave said. “Van Ness just happened, but ever couple of years there is a 彗星 that visibly breaks up into fragments, maybe about 6 彗星s in the last 10 years — excluding the Kreutz-sun-grazer family of 彗星s which split and vaporize on a regular basis.”
Unfortunately, the likely demise of 埃琳宁彗星hasn’t put a lid on the doomsdayers who have predicted earthquakes or three days of darkness or a collision with Earth.
“The doomsdayers are just saying that more bad things will happen!” laughed Musgrave. “But you have to remember that when a 彗星 breaks up, the fragments stay in the same orbit. If it evaporates, you’ll have a mass of rubble and gas on the same orbit. People don’t seem to get that space is big, really big, and when a 彗星 breaks up it follows Newtons Laws and the fragments will slowly draw apart, but over the timescale that we see them, the difference will be so miniscule.”