You are here
Comet ISON – How to Talk about it like a Boss. Nature Space and Nature 

Comet ISON – How to Talk about it like a Boss.

Comet ISON is one of the best comets to observe in recent memory.  I’ve been excited about for a while now.

Not since my original article on P/17 Comet Holmes have I written or cared to explore other comets.

In the coming weeks, lots of non-space geeks will talk about it, and even have the chance to see it with the naked eye.  In fact, some speculation exists that once the comet makes it’s way around the “back” of the Sun and shoots into the reaches of space, the tail could be as long as a horizon.  Neat.

So I’m writing this article, not to delight in the scientific minutia and make some kind of insight to the scientific and intellectual community, I’m writing this for the lay-person.  Someone who might gander up at the stars at night, or marvel in “big boy toys” or the moon-shot of the late 60’s.

Straight-up Questions about Comet ISON

Here’s the questions, ranging from basic to intermediary.  Enjoy!

What is a comet exactly?

A huge chunk of ice and rock zipping through space.  Usually they have a tail, which is a cloud of melting ice trailing behind the object.  The tail gets longer as it approaches the Sun.

What about this comet, comet ISON?

This comet was discovered in 2012 by a group called “ISON”.  They discovered it, they get to name it.  The true name is C/2012 S1 ISON.  It’s about 2km’s wide.  There’s a method to this naming, which i won’t go into here.  The comet is hyperbolic, meaning it has more energy given to it than it needs to orbit the sun, obviously it was formed by something knocking into something else.  Also, this explains why it is new.

What makes this comet special?

This is a relatively young comet that has the predictions of becoming a wonderful sight.  It has an orbit that brought it very close to Mars, and will most likely have a fantastic tail if it survives the melting when it gets close to the Sun.  We’ve known about this comet for a while, and it’s exciting to watch the close pass by the Sun.

How do I describe the orbit?

The orbit is Hyperbolic, also the orbit has it swinging precariously close to the sun.  We’re just not sure if it’s going to make it through the ordeal.  If it does, the burn-off tail will probably be HUGE.

Will it make it around the Sun?  New projections from NASA indicate that the comet will skim the solar surface of the Sun at perihelion.

In general, the comet should pass above earth’s North Pole around New Year’s Eve.

When will I be able to see it?

You can see it now, wait for it to wrap around the sun, and see it after (way better, brighter).

Also known as the “Christmas Comet 2013”, the best time to view this comet, if it survives it’s brush with the Sun, will be right around December 25th.

In astronomy, we use a measurement to describe how bright it is.  Right now it’s “magnitude” is just bright enough for some larger amateur astronomer backyard telescopes.   It’s visible now in the early dawn, but will soon enter a period of weeks when it’s too close to the Sun to observe (it will be daylight for us then!).



Great Links

Heavens Above.

Love this site.  Here’s a real-time information overview on the specifics of exactly where the comet is, how bright it is, and where to look in the sky for it.  Remember to set you location on Earth to get accurate information!

Comet ISO from


Right ascension 11h 11.0m
Declination 6° 32′
Constellation Leo
Distance from Earth 1.238 AU
Last observed magnitude 13.7
Date of last reported observation 30/10/2013
Altitude -43.0°
Azimuth 279° (W)
Angular separation from Sun 52.1°
Ecliptic latitude 1.5°
Distance from Sun 1.003 AU
Perihelion 0.012 AU
Eccentricity 1.000002
Inclination to ecliptic 62.4°
Speed relative to Sun 42.053 km/s

See the above table?  You only really need to know a few “sciency” phrases

  • Altitude – how high up you need to look to see it.  0 degrees is the horizon, 90 degrees is straight above.  Minus means it’s below the horizon currently.  Make an “inclinometer” to help you guage the altitude.
  • Azimuth – cardinal direction.  0 degrees is north, 180 is south… etc.
  • Distance from … – expressed in “AU’s”, which means distances from the earth to the sun.  Right now it’s almost 1, meaning, about the same distance away from the sun as we are.
  • Last observed magnitude – how bright.  The lower the number the better.  Most telescopes can start seeing objects around 13 or 14, and the numbers can get down to 0, or even in the negatives (-2.2 etc.) , for example, the ISS is visible clearly with the naked eye around 2.0 and is dazzling around -2.

Great photo site.  Lots of user submissions, sometimes with just normal backyard photography (point and shoot zoom lense, etc.).  Sign up for their alerts!


NASA has a great timeline of when all of their instrumentation will be able to see the comet.  Already, we’re seeing some amazing photos come back from Hubble, MESSENGER, and STEREO satellites.

Great time-lapse of the projected “fly-by”.



Related posts

3 thoughts on “Comet ISON – How to Talk about it like a Boss.

  1. G47

    How many comets have been visible to the naked eye in the last ten years vs. how man in the next ten years?

    Just thinking… is this going to be a better decade than the last? I think that public astronomy was on a downer for the last ten years.

    1. realworldnumbers

      What a fantastic idea. I sense another article coming on. Quantifying the downer of the last ten years of astronomy.

  2. […] weather has been just terrible to me.  I’ve been trying to check out Comet ISON, but it’s sitting so low in the horizon, and those clouds from Lake Ontario keep everything […]

Leave a Comment