• Blog Stats

    • 1,224,815 hits

Here we go again…

 

After being out of the media spotlight for a few years, that ugly, green-brown rock you see above is about to hit the headlines again. In a big way.

You see, that ugly looking chunk of stone is actually “ALH84001″, the most famous meteorite in history. ALH84001 is one of those rare “martian meteorites” – a piece of rock that was blown off Mars by an asteroid impact some 16 million years ago, and landed on Earth millions of years later, specifically on the snowy plains of Antarctica, as a “meteorite”. Its name tells you all about its discovery history: “ALH” stands for “Allan Hills”, which is a region of Antarctica. “84” tells you it was found in 1984. ( And, um, I’m not sure what the “01” bit stands for, to be honest! ) It sat there in Antarctica for many thousands of years before it was found by meteorite-hunting scientists, but it wasn’t recognised as being from Mars at the time, and was basically locked away in a vault for years until it was examined. That’s when the scientists discovered it was actually from Mars, and took a closer look – a much closer look.

Finally, in 1996 (oh.my.god! That’s 13 years ago!!!!), on August 6th, a group of NASA scientists announced that their studies of the inside of the meteorite had revealed… this…

Structures that looked suspiciously like the fossilised remains of bacteria… Maybe bacteria from Earth, that had gotten into the rock after lt landed, died and become preserved within it… or… or…

…possibly… maybe… perhaps… you know… bacteria from Mars..?

The world went absolutely crazy.

“LIFE ON MARS!” “MARTIAN FOUND IN SPACE ROCK!” screamed the headlines, right around the world. The meteorite was the lead item on every news report that evening, and President Clinton called a special media event to hail the discovery and praise the team for their work.

It was a thrilling time for space enthusiasts like myself. I well remember sitting in a pub that very night, with members of the Cockermouth Astronomical Society, discussing the story. Of course, as a) a firm believer in extraterrestrial life, and b) a lifelong Mars nut I was beside myself with excitement, almost unbearably so, but even I had to take a deep breath and remind myself that the results were by no means conclusive, that a lot – a lot! – of work had to be done before anyone was in a position to declare, confidently, that life had indeed been found on Mars. Calm down, calm down – the jury was still very much out.

In the years since then, studies of ALH84001 have continued, quietly, behind the scenes, out of the way. The arguments for and against have ebbed and flowed, back and forth, between “yes, it contains evidence of life!” and “no, that’s not evidence of life, it’s something else entirely”. Some scientists have embraced ALH as a kind of “Holy Grail”, insisting it is proof of life off Earth; others have dismissed it as a great big rocky red herring, insisting the structures seen are too small to be bacteria, and/or could have been formed naturally, and have criticised the “Mars rock team” for bad methods, jumping to conclusions, and generally getting it wrong.

Well, word is leaking out, slowly, that the team behind the original studies of ALH84001 have been doing some new work on the meteorite, using equipment and techniques unavailable 13 years ago to study the magnetite crystals and carbonate discs inside the meteorite, and are now confident that those structures found inside the rock make a very compelling case for the existence of life on Mars in the past.

There’s nothing official “out there” yet, but the story has been “broken” by Craig Covault over on Spacflightnow.com, a paper is going to be published in a scientific journal, and it seems that NASA will be commenting officially on the story within the next few days. So, get ready for an explosion of media interest in Mars again, reporting breathlessly on the prospect of life on Mars. Already The Sun newspaper here in the UK has picked up the story, and is reporting it in a typically restrained, low-key way…

Interesting times lie ahead…! 🙂

UPDATE: Thanks to Alice from Aliceastroinfo for letting me know that the paper has already been published, and is available here:
http://adsabs.harvard.edu/abs/2009GeCoA..73.6631T (note: there’s a charge to download it). Thanks Alice!

Advertisements

6 Responses

  1. The paper is published:
    http://adsabs.harvard.edu/abs/2009GeCoA..73.6631T

    Of course, you currently still have to pay $30 to ScienceDirect to get a full copy … but it is out there.

    -Alice

  2. […] Marsbakterien nun plötzlich in die andere Richtung schwingt … (Spaceflight Now 24., IO9 25., Cumbrian Skies […]

  3. “And even previously harsh critics of their work are now supporting them” – who exactly would that be? From what I’ve read the referees of the paper were happy (otherwise it wouldn’t have been published – d’oh), but I’ve yet to see those who attacked the 1996 work (and destroyed all of it but the magnetite claim) react to the new analysis.

  4. The “001” in ALH84001 means it was the first meteorite picked up during that field season in Antarctica. Now, to take a look at this paper. I’m skeptical…

Leave a Reply

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

WordPress.com Logo

You are commenting using your WordPress.com 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 )

Google+ photo

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

Connecting to %s

%d bloggers like this: