Matthew Knight's blog

Your chance to ask the experts about Comet ISON (Part 2)

Comet ISON made headlines as it had a spectacular (and apparently fatal) close encounter with the Sun last week. Here is your chance to find out the latest about the comet from the scientists who have been studying ISON since its discovery just one year ago.

Your chance to ask the experts about Comet ISON

As Comet ISON nears its very close encounter with our sun in the early afternoon (EST) on Nov. 28, there are two chances to find out the latest about the comet from the scientists who have been studying ISON since its discovery just one year ago.

What might happen to Comet ISON from here on out?

This post was written by Matthew Knight with input from Dr. Carey Lisse.

November is here and Comet ISON is just a bit over three weeks from it closest approach to the Sun (astronomers call this “perihelion”). As we’ve said from the beginning, it is impossible to predict exactly what ISON will do. However, given numerous observations of previous comets, we do have a pretty good idea of the range of possible outcomes. Now that ISON has almost completed its journey from the Oort Cloud to within a million miles of the Sun’s photosphere, it seems like a good time to go over what might happen.

Why does ISON look green?

The first papers about Comet ISON are beginning to appear

We quietly rolled out a new page on the CIOC website recently: publications. You can navigate to it from anywhere on the site from the “Comet ISON” tab then selecting “Publications” from the drop down menu. Why am I bringing your attention to this page? Well, for one, I have a paper there that I want people to read ☺ But also, because there are already some interesting ideas about what has been going on with ISON and what will happen soon.

How Bright is Comet ISON?

The CIOC frequently gets asked how bright Comet ISON will be at a particular time in the future. Our standard response is that comets, especially ones entering the inner solar system for the first time (like ISON), behave unpredictably and it is therefore impossible to reliably predict what ISON will do. What we don’t often mention is that it is actually rather difficult to say conclusively how bright ISON or any other comet is right now!

You are probably saying to yourself “That’s ridiculous. Just take an image and measure how bright it is!” If only it were that easy…

Why I’m *still* not worried about ISON’s brightness

As you have probably heard, Comet ISON was recovered last week as it emerged from solar conjunction. This was big news because it was the first time ISON had been observed since June and there has been a lot of speculation about how bright it would be. So how bright is ISON now? About what we expected it to be!

Why I’m not particularly worried about ISON’s brightness

Comet ISON is currently hiding behind the Sun and, with no observations of it since early June, there has been a fair bit of speculation recently about what it has been doing. Unfortunately, much of this has been has been of the negative variety, and I’d like to address it clearly here.

It’s premature to write ISON off.

How unique is Comet ISON?

A journalist asked me recently “When is the last time there was a dynamically new Oort Cloud comet that was also a sungrazer? In other words, how long has it been since the last Comet ISON?” It is an interesting question that other people will likely ask, so I thought it was worth discussing here.
Subscribe to RSS - Matthew Knight's blog