Comet Siding Spring – Big Hype, Little Show

by Alan Eggleston

What was that blotch on my computer screen Sunday?

There was a lot of excitement in the air Sunday, October 19, 2014. Comet Siding Spring was approaching within 86,000 miles of Mars (roughly a third of the distance from the Earth to the Moon); it was once even thought to be destined to collide with Mars, although refinements to its orbit finally showed that wouldn’t happen. Once astronomers realized it would simply be a close encounter, however, the buzz amped up, because although we couldn’t be eyewitnesses to the event itself, humans had equipment at Mars that would let it be the next best thing to being there.

Let the imaginations soar!

Comet Siding Spring is traveling at 125,000 mph – 56 km/sec – and spewing out 220 lbs of dust particles per second (around 800,000 lbs per hour!). If you were on Mars you would see a tail and if you stood still long enough, you could see it inch along among the stars above you. NASA Curiosity Rover would be able to look up and catch a glimpse, although as of now I haven’t seen pictures. Mars orbiter and MAVEN are among the assets in orbit around Mars in position to take pictures above Mars’ atmosphere – they were moved behind Mars to protect them as comet Siding Spring passed by, then moved back in place again to take images. Again, nothing has been published yet. A lot of what you will see online so far are artist impressions of what the comet might look like and animations or infographics explaining the comet’s movements.

I read the Twitter thread at #SloohComet and watched the Slooh Comet Siding Spring live coverage. Once again, the astronomical community got excited about something for which there was very little return. Slooh gives citizen scientists – everyday people who want access to professional-grade telescopes – access to major events, and yet, what they saw was little more than looking at a distant comet out your backyard view through binoculars. It reminded me of the hype and excitement over the aurora borealis that never pans out or meteor showers that don’t meet expectations or the grand-show comet that doesn’t quite make it.

(I’m not posting an image this time – why bother?)

I suspect that when the actual photos from Mars rovers and Mars orbiters  come in, that’s when the actual excitement will meet expectations.  And it’s my suggestion that when an event like this comes we all be patient and wait till the scientists finish their work. For now, we have little to show for the hype.

Update: “Opportunity Rover Spots Comet Siding Spring from the Surface of Mars!” (Universe Today.) Not as spectacular as I’d hoped, but still better than we saw from Earth!

Update II: “Wow! This Hubble Telescope Photo of Mars with a Comet is Amazing” ( Now, this is more like it. Definitely not hyperbole from these science writers and editors.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s