Our Place in Space: Jezero Crater

Hello, friends!  Welcome to Our Place in Space: A to Z!  For this year’s A to Z Challenge, I’ll be taking you on a partly imaginative and highly optimistic tour of humanity’s future in outer space.  If you don’t know what the A to Z Challenge is, click here to learn more.  In today’s post, J is for…

JEZERO CRATER

Someday, I’d like to help dig up dinosaur fossils.  That’s apparently a thing pretty much anybody can volunteer to do.  Someday, I’d also like to live on Mars.  In the distant future, it may be possible to do both of those things.  Places like Jezero Crater on Mars may be full of ancient Martian fossils!

If you look at satellite images of Jezero Crater, it’s pretty obvious it used to be full of water.  You can see what appears to be a dried-up river bed snaking its way across the Martian landscape.  Where that river meets the crater, there’s a breach in the crater wall and a large river delta where the river would have spilled into the crater basin.

Right now, NASA’s Perseverance Rover is driving around that river delta, scoping the place out, examining the sediments and clays found in the region.

Okay, I may have taken some creative liberties with the cartoon above.  If life ever did evolve on Mars, it would have been short-lived.  All of Mars’s lakes, rivers, and oceans would have dried up fairly early in the planet’s history.  It is highly unlikely that anything as complex as fish or seaweed could have developed, and there certainly wouldn’t have been anything as awesome as a Martian dinosaur.

But in places like Jezero Crater, simple microorganisms could have been plentiful.  These microbes may even have joined together, creating larger structures like the bacterial mats we sometimes find here on Earth.  That’s kind of icky, I know, but it could have happened, and those bacterial mats may still be there, preserved as fossils beneath all that red dust.

I don’t expect questions about life on Mars (past or present) to be answered any time soon.  Even if one of our Mars rovers did stumble upon something that looked like a fossilized bacterial mat, there would be scientific debates for years—decades, even—over what that fossil-looking-thing really is and what it’s presence on Mars really means.  We’ve been through this before, when scientists found “bacteria shaped objects” inside a Martian meteorite.  Something can look like a fossilized bacterium, and yet not be a fossilized bacterium.

But someday in the distant future, we will know, one way or the other, if life ever existed on the Red Planet.  And perhaps in that distant future, humans living on Mars will volunteer to help dig up fossils in Jezero Crater, or other places very much like it.

Want to Learn More?

Here’s an interactive map from NASA showing the Perseverance Rover’s current location.  You’ll have to zoom out a little to see all of Jezero Crater.  If you do, you’ll see that the dried-up river (marked Neretva Vallis) and river delta I mentioned are pretty obvious.

And here is a NASA press release from a few years back, announcing Jezero Crater as the Perseverance Rover’s landing site and explaining why the crater was selected.

Also, here’s an article from Space.com about that Martian meteorite I mentioned, the one with those “bacteria shaped objects” inside.

Sciency Words: Heartbeat Tone

Hello, friends!  Welcome back to Sciency Words, a special series here on Planet Pailly where we talk about those weird and wonderful terms scientists use.  Today’s Sciency Word is:

HEARTBEAT TONE

Last week, I watched NASA’s live coverage of the Perseverance rover landing on Mars.  Naturally, I had a notepad ready, and I picked up quite a few new scientific terms.  My absolute favorite—the one that brought the biggest smile to my face—was “heartbeat tone.”  I love the idea that Perseverance (a.k.a. Percy, the Mars Rover) has a heartbeat.

As this article from Planetary News describes it, Percy’s heartbeat tone is “similar to a telephone dial tone.”  It’s an ongoing signal just telling us that everything’s okay.  Nothing’s gone wrong, and everything’s still working the way it’s supposed to.

Of course, other NASA spacecraft use heartbeat tones as well.  According to two separate articles from Popular Mechanics, the Curiosity rover on Mars and the Juno space probe orbiting Jupiter also send heartbeat tones back to Earth.  And that article about Juno offers us a little bit of detail about what Juno’s heartbeat actually sounds like: a series of ten-second-long beeps, sort of like very long dashes in Morse code.

Based on my research, it seems like the earliest NASA spacecraft to use heartbeat tones (or rather, the earliest spacecraft to have this heartbeat terminology applied to it) was the New Horizons mission to Pluto, which launched in 2005.  As this article from Spaceflight 101 explains it, New Horizons’ onboard computers monitor for “heartbeat pulses” that are supposed to occur once per second.  If these pulses stop for three minutes or more, backup systems kick in, take over control of the spacecraft, and send an emergency message back to Earth.

So, I could be wrong about this, but I think this “heartbeat pulse” or “heartbeat tone” terminology started with New Horizons.  To be clear: I’m sure spacecraft were sending “all systems normal” signals back to Earth long before the New Horizons mission.  I just think the idea of using “heartbeat” as a conceptual metaphor started with New Horizons.  But again, I could be wrong about that, and if anyone has an example of the term being used prior to New Horizons, I would love to hear about it in the comments below!

P.S.: I recently wrote a post about whether or not planets have genders.  With that in mind, I was amused to note in NASA’s live coverage that everyone kept referring to Perseverance using she/her pronouns.  However, the rover has stated a preference for they/them on Twitter.  So going forward, I will respect the rover’s preferred pronouns.

Sciency Words: Perseverance

Hello, friends!  Welcome back to Sciency Words, an ongoing series here on Planet Pailly where we talk about science or science-related terms.  Today on Sciency Words, we’re talking about:

PERSEVERANCE

Mars rovers are among the most advanced pieces of technology we humans have ever produced.  And by a longstanding tradition dating back to the Sojourner rover in 1997, the official names for NASA’s Mars rovers are chosen by school children.

The Perseverance rover, currently on route to Mars, was named by 7th grader Alex Mather.  He won an essay contest.  Here’s a video of Mather reading his essay, followed by a quick Q and A session with some NASA officials.

You know, after listening to Mather’s essay, I have to agree.  Perseverance is the right name for our newest Mars rover.  It’s even more right of a name now than it was back in March, when the name was announced.

Things are scary here on Earth.  So many people are suffering.  So many people are struggling.  So many lives are being needlessly lost.  But I do believe, as Mather says in his essay, that perseverance is our most important quality as a species.  In the end, humanity will persevere.