You are here


Comet Dust in Mars' Atmosphere: How Do the Orbiter Observations Relate to the Siding Spring Dust Models?

NASA held a telecon/press conference on November 7 to announce the results from the MAVEN, Mars Express (MEX) and Mars Reconnaissance Orbiter (MRO) observations that were obtained during the encounter between Mars and comet Siding Spring. The broadcast can be found here: ( During this event, there were presentations that showed three fascinating pieces of evidence indicating that a significant amount of comet dust was deposited into Mars' atmosphere during the encounter.

A Few Days Later

Well, we've learned that the Comet, Mars, and the Mars spacecraft are all A-OK. We're seeing fantastic real time and time-lapsed monitoring from the Pro-Ams of the flyby. The Mars surface rover Opportunity has detected the comet in the Martian sky, despite relatively strong dust storms, adding to the long list of achievements for this amazing robotic explorer. We're finding out from MRO/HiRISE that Comet Siding Spring has a very small, sub-km radius nucleus, like its fellow Oort Cloud interloper Comet ISON last year, with which it shares a smiler long term lightcurve.

It’s 6 AM And All’s Well

It's now 6 AM EDT on the 20th of October 2014, 18 hrs after the close flyby of Comet Siding Spring, and by all accounts the Mars spacecraft are all fine, as is the Comet. Now we get to wait and listen over the next few days to see what kind of imagery and spectroscopy of the flyby event we have obtained.

Good Luck Today For the Encounter!

Well, the big day is finally here, the one we have planned for for so long. We've got an intact, active, changing comet about to swing close
by Mars! Best of luck to everyone weather- and telescope h/w-wise. Keep in touch with us here if you have important news to report. From
our side, we expect to be hearing more and more over the next few days, starting mid-Sunday night, about what happened at Mars, as the
various spacecraft download their data and it gets calibrated, validated, and distributed on Earth. Stay tuned!

Close Encounters of the Awesome Kind

Who needs words when a picture can tell a thousand? And oh what pictures!

Feast your eyes on this small selection of close approach images from the past couple of days, taken by some extraordinarily talented astronomers and astrophotographers! (I'll update this if/when I get new pics - feel free to email them to me: [email protected], or send us details/link via our contact page, and I'll post the best ones.)

Drawing Parallels

Here we are - just one day before the "big event". In many ways it brings back memories for me from last year, when I was perched atop Kitt Peak in Arizona, waiting for comet ISON to have its shining moment in the Sun.

Couple of Brief Items

So there are just about 5-days to go until comet Siding Spring buzzes past Mars, and everyone is getting into gear to obtain some great new science! I want to keep this post brief, but there are a couple of news items I want to share.

Exciting Times

We're now less than two weeks away from Comet Siding Spring buzzing ridiculously close to Mars, and the excitement is building - in both good and bad ways...

What is going on with Siding Spring’s lightcurve?

As can be seen on the Current Status page, C/2013 A1 Siding Spring’s reported brightness declined considerably more than expected over the last week or so. We chose not to speculate about what might be causing the decline on that page, but I’m going to take advantage of the freedom provided by a blog post to expand on what I think might be going on.

A View from Another World

Unfortunately, and in spite of the hype we are giving it, comet C/2013 A1 (Siding Spring) is not going to be a spectacular object in the night sky. Faint, and distant from Earth, only experienced observers with moderately sized telescopes have a reasonable chance of viewing it. Well, that is in our night sky, at least...


Subscribe to RSS - blogs