Wednesday, February 4, 2009

Comet Lulin disconnection event

Today we wanted to make some wide-field imaging of comet C/2007 N3 (LULIN), in search for large scale structural features. In our image (see below, details in the caption; click on it for a bigger version):

is clearly visible the characteristic dichotomy of this comet: a dusty anti-tail pointing toward the Sun (i.e. to South-East) and the highly structured ion (plasma) tail toward West,Northwest. This uncommon configuration, is due to the particular geometric circumstances occuring during these nights, with the comet seen nearly head-on as seen from Earth.

Moreover, we were lucky enough to capture an intriguing phenomena: in our images is clearly visible a nice disconnection event (DE) in the plasma tail of the comet (evidenced by a red circle in this rendition):

The DE indicates that the comet has recently passed through a disturbance in the magnetic field carried by the solar wind, that destroyed the original plasma tail, creating a new one. The separation of the two ion tails indentified by the DE, is visible in our image as a kind of elongated and diffuse "knot" along the plasma tail.

A 3x zoomed view of this feature is available here:

The "knot" is dragged tailward by the solar wind, and will dissipate soon. More events like this are expected in the near future, when comet LULIN will approah Earth. Comet aficionados, heads-up!

by Ernesto Guido, Giovanni Sostero and Paul camilleri


Juan Antonio HenrĂ­quez Santana said...

It's not a very frecuent event...

Another example of good job.

Congratulations and thank you for the show...

Anonymous said...

is this part of tail which is gone away made of cyanure like the coma of the comet? can we think it is possible that it will stay any time on the way of Earth because they said that comet Lulin walks on the same level than earth ? there is no wind in space . Thank you for answer.

Team said...

Normally cometary plasma tails are made of CO+ and H2O+; this one in particular, seems to be mainly constitute by CO+ (due to its blue color). In space there is no wind, in the sense we usually intend on Earh; however the Solar System is permeated by a flow of charged particles originating from our star, referred to by the astronomers as "solar wind". The solar wind is the main responsible of the evolution of cometary ion tails, like in this instance. Anyway, there is no risk of getting the stuff ejected by comet LULIN on Earth, since their orbits are not intersecting. Thanks for asking

by Remanzacco Team

Anonymous said...

thank you very much for your answer;
I often thougth that it had been possible that dinosaurus had been poisoned by that kind of comet. Because a lot of animals which lived in the sea had been killed too at the same time..
anonymous friend