ISON Image of the Week

A Backyard Comet  (Sep 30, 2013)

This beautiful photograph taken by Canadian amateur astronomer Malcolm Park on Sept.29, 2013, does not show comet ISON itself but illustrates exactly where in the sky it can be seen by backyard astronomers with only moderate-sized telescopes. [Image credit: Malcolm Park, NYAA]
We now have less than two months to go until comet C/2012 S1 (ISON) has its close brush with the solar corona and, at time of writing, it still seems to be a healthy Oort Cloud comet!

Accordingly, as word begins to spread among the astronomy community of ISON's increasing visibility, we at the CIOC are getting an increased number of questions from people asking us "where in the sky is the comet?". That's a great question, and we could reply by pointing to the MPC's ephemeris for the comet, which is essential for actual imaging of the comet. But numbers only tell part of the story, so this week we've chosen instead to actually show you where ISON is right now, courtesy of this beautiful image taken by Canadian amateur astronomer Malcolm Park.

The photo was taken by Malcolm in the early hours of September 29, 2013 from Oak Heights, Ontario, at the North York Astronomical Association's observatory. While comet ISON itself is far too faint to see in this photograph, it was successfully viewed through the eyepiece of a telescope and imaged by Malcolm and three of his friends that morning.

"We had phenomenal weather over the weekend, and last night was exceptionally clear for our area with good seeing and transparency.", Malcolm told the CIOC. "A group of four of us stayed up the whole night observing, imaging, and enjoying the views. Mars rose after 3:00 a.m. but wasn't high enough to find the comet until closer to 4:00 a.m.. We found it in my friend's 18" Starmaster dobsonian telescope. The views in this instrument are stunning!"

Comet ISON has been gradually brightening up over the past few weeks, and while reported magnitudes will always differ from observer to observer, an increasing number are now reporting values of magnitude 12 or brighter. If ISON continues to behave and brighten as we expect, it should become an increasingly easy target at least for the first few weeks of October before it begins to edge closer to the Sun in the sky. But for those of you with clear skies and a reasonable horizon right now, Malcolm offers these words of encouragement: "We have officially crossed over into new territory. Backyard astronomers can now see this comet!"

One final thing to note here is ISON's apparent proximity in the sky to the planet Mars. Often in astronomy, such events are simply line-of-sight effects, but here that's not the case: ISON really is close to Mars! Over the next few days, a fleet of NASA and ESA spacecraft at or on Mars will be attempting to image ISON as it passes just 0.07AU (10.8 million km, 6.7 million miles) from the Red Planet. If these attempted observations are a success, expect to see some Martian astrophotography appearing on this website in the coming weeks!

Every week this year we will put up a new image related to Comet C/2012 S1 (ISON). If you have a cool image you'd like us to consider, please send it to, along with a description and any credits you would want applied. We'll contact you if we choose to use your image on the CIOC Website.

See our ISON Image of the Week Archives for earlier picks!