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: Safety Ellipse

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

SAFETY ELLIPSE

I don’t know about you, but when I’m trying to dock my shuttle pod with another spaceship, I like to take a few long, leisurely loops around that other spaceship first.  You know, like this:

Spaceships are pretty!  Who wouldn’t want to get a good look at them from every conceivable angle before completing docking maneuvers?  But it turns out that circling round and round a spaceship like this is not just for admiring the view.  It’s also for safety!  As explained in this paper:

A “safety ellipse” is an out-of-plane elliptical periodic relative motion trajectory around the primary spacecraft such that the trajectory never crosses the velocity of the primary.

That clear things up?  No?  Okay, how about a quote from this paper instead:

This paper defines a safe trajectory as an approach path that guarantees collision avoidance in the presence of a class of anomalous system behaviors.

Still confused?  Here’s a short video demonstrating what a safety ellipse (a.k.a. a safe trajectory) looks like:

Basically, if your shuttle pod experiences engine failure or any other major malfunction, flying in a safety ellipse ensures that you will not collide with the ship you were trying to dock with.  At least not for a good, long while.

I first heard about this term the other day while watching the livestream of the SpaceX Dragon capsule approaching and docking with the International Space Station.  Several times, the livestream commentators mentioned that Dragon was utilizing a “24 hour safety ellipse” or “24 hour safe trajectory,” meaning that if anything went wrong, mission control would have at least 24 hours to fix it before Dragon and the I.S.S. collided.

So remember, friends: the next time you’re going to dock with another spacecraft, do that out-of-plane elliptical periodic relative motion thing.  In other words, circle around the other ship a few times before making your final approach to dock.  It’s for safety reasons.

P.S.: It’s also for enjoying the view.  Spaceships are pretty!

Sciency Words: Orthofabric

Hello, friends!  Welcome to Sciency Words, a special series here on Planet Pailly where we explore the definitions and etymologies of scientific terms.  Today on Sciency Words, we’re talking about:

ORTHOFABRIC

If you’re planning to spend any amount of time floating around in outer space, you need to dress appropriately.  You’ll need protection against solar and cosmic radiation.  You’ll need protection against extreme temperatures, both extreme cold and extreme heat (direct sunlight in the vacuum of space can make things super hot super quick).  Oh, and there are lots of tiny micrometeoroids whizzing about up there.  You’ll need protection against those too.

Around the same time that the space shuttle program got going, NASA started using a new fabric for the outermost layer of their spacesuits.  That fabric is still used today for spacesuits aboard the International Space Station.  It’s called Orthofabric (sometimes spelled with a hyphen: Ortho-fabric).

Orthofabric is made by a company called Fabric Development Inc., based in Quakertown, PA.  Orthofabric is made using three different synthetic fibers: Gore-Tex, Nomex, and Kevlar.  As reported in several research papers (like this one or this one), Orthofabric consistently holds up well against the harsh conditions found in space.  That’s why NASA keeps using it.

For these Sciency Words posts, I think it’s important to say something about the etymology of the word we’re talking about, but I had an extremely hard time finding any sort of etymology for this one.

The prefix “ortho-” comes from a Greek word meaning righteous, virtuous, or pure (hence the word orthodox).  “Ortho-” can also mean upright or straight (hence the word orthopedic).  But what do either of those meanings have to do with Orthofabric?  The prefix “ortho-” also has a specialized meaning in chemistry, but based on my research, the chemistry sense of “ortho-” didn’t seem relevant to Orthofabric either.

So finally, I picked up the phone, called Fabric Development Inc., and asked.  I was told the name Orthofabric was chosen after some back and forth consultation with NASA.  The name doesn’t mean anything in particular.  It’s just a name.  I guess somebody thought it sounded good.  End of story.

P.S.: NASA’s new Perseverance rover will be searching for life on Mars, but as a little side experiment Perseverance is also carrying a small sample of Orthofabric, along with samples of other commonly used spacesuit materials.  NASA wants to see how well these spacesuit materials hold up in the windy and dusty Martian environment.

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.

Sciency Words: Somaforming

Hello, friends, and welcome once again to Sciency Words.  Each week, we take a closer look at some new and interesting scientific term so we can expand our scientific vocabularies together.  This week’s Sciency Word is:

SOMAFORMING

I’d like to begin this post with a quote.  This comes from the 2019 Sci-Fi novella To Be Taught, If Fortunate by Becky Chambers.  As the protagonist of that book explains, we humans are a remarkably versatile species, able to adapt to pretty much any environment—or at least any environment Earth has to offer.

But take us away from our home planet, and our adaptability vanishes.  Extended spaceflight is hell on the human body.  No longer challenged by gravity, bones and muscles quickly begin to stop spending resources on maintaining mass.  The heart gets lazy in pumping blood.  The eyeball changes shape, causing vision problems and headaches.  Unpleasant as these ailments are, they pale in comparison to the onslaught of radiation that fills the seeming void.

I have rarely seen the dangers of human spaceflight so artfully or so succinctly explained as in this book.

Even before Yuri Gagarin became the first human in space, scientists knew space would be rough on the human body.  They did not know specifically what might go wrong, but they knew there would be trouble.  The obvious solution is to create an environment that is safe and comfortable for human beings.

But as early as 1960, some scientists were considering an alternative solution.  Rather than creating space environments that are suitable for human life, why not modify human life to be suitable for the environment of space?  This was the idea proposed by American research scientists Manfred Clynes and Nathan Kline in their 1960 paper “Cyborgs and Space.”

Clynes and Kline proposed some rather drastic surgical changes to the human body.  They make it sound quite easy.  Just rip out a bunch of internal organs.  Replace those organs with synthetic parts.  Pump the patient/astronaut full of drugs and use hypnosis to suppress any psychological issues that might come up during or after the process.  And now you have a human being who’s ready to go to space!  Or you have a human being who’s dead on the operating room table.  One, or the other!

Clynes and Kline introduced the word “cyborg” to describe the half-human/half-machine person they proposed to create.  What Becky Chambers describes in To Be Taught, If Fortunate sounds a little bit safer and a lot less dehumanizing.  And Chambers introduces a new term to describe the transformation her characters undergo: somaforming.  The word is created by analogy with the word terraforming, with the Greek root word “terra” (Earth) being replaced with the Greek root word “soma” (body).

As the protagonist of To Be Taught, If Fortunate explains it, human space explorers come as guests, not conquerers.  The age of colonialism is long behind us. And being good guests, we don’t want to demand too much of our hosts or cause our hosts too much trouble.  To quote Chambers’ book once more: “I have no interest in changing other worlds to suit me.  I choose the lighter touch: changing myself to suit them.”

And I think that is a wonderful sentiment!

As far as I can tell, the word somaforming has not yet been picked up by the scientific community.  But plenty of words from science fiction have been adopted by scientists.  I have a suspicion that this is going to be one of those words.

Next time on Planet Pailly: Oh no!  I made a mistake in an old blog post, and I need to issue a retraction!

Sciency Words: Colony

Hello, friends!  Welcome to another episode of Sciency Words.  Normally on Sciency Words, we talk about those strange words scientists use, but today we’re going to talk about a word scientists—or at least some scientists—would prefer to stop using.  And that word is:

COLONY

Mars is so eager for humans to come visit and maybe even stay permanently.  And plenty of humans are eager to do just that!  We’ll bring life to Mars.  Not only that, we’ll bring civilization and culture.  One might say it is humanity’s destiny to colonize Mars.

But is this language of “colonization” and “destiny” too evocative of European imperialism?  Some think so, and they would ask that we stop using such colonialist language when we talk about space exploration.

Now I want to be clear about where I’m coming from on this: I try my best to call people by the names and terms they prefer to be called, and if I find out that the language I use offends somebody, I’ll do may best to change.  Some would accuse me of being too P.C., but I think it’s just good manners.

And I have found that if you make an effort to be respectful and accommodating to others, others will make an effort to be respectful and accommodating to you, and in general they’ll be more willing to forgive you if/when you do slip up and say something unintentionally hurtful.

So a few years back, when I came across this article from National Geographic, I started reading it with an open mind and a willingness to change.  But by the end of the article, even I felt like this was an example of political correctness run amok.  The word “colony” is offensive.  So are the words “settlement” and “frontier.”  Okay.  What words should I use instead?  Even that National Geographic article seems to concede at one point that we don’t have many workable alternatives to these terms.

But this concern does seem to be coming up more and more.  Plenty of people in the scientific community are shying away from words like colony and colonization.  Bill Nye (the Science Guy) says he avoids the word colony, and this official glossary of SETI terminology warns that “settle” and “colonize” may have certain negative connotations for some people.

So at this point, I’m not sure what to think.  What about you?  Do you think this is much ado about nothing, or should we really start looking for alternatives to words like “colony” or “settlement” in our space exploration vocabularies?

Next time on Planet Pailly… I actually don’t have anything planned yet for my next blog post.  We’ll probably just talk about more space stuff.

Sciency Words: Bunny Hopping

Sciency Words: (proper noun) a special series here on Planet Pailly focusing on the definitions and etymologies of science or science-related terms.  Today’s Sciency Word is:

BUNNY HOPPING

So yesterday I was reading up on the latest spacesuit design from NASA, and I came across a term that I don’t remember ever seeing or hearing before.  In this article from Space Daily, NASA Administrator Jim Bridenstine is quoted as saying: “If we remember the Apollo generation, we remember Neil Armstrong and Buzz Aldrin, they bunny hopped on the surface of the Moon.”

This left me wondering: do people really use the term “bunny hopping” to describe how Apollo astronauts moved about on the Moon?  I tried really hard to trace the etymology of this term.  I didn’t find much, but honestly, when you see clips like this one, it’s easy to figure out where the term came from.

In my previous research on this topic, I’ve seen this method of locomotion referred to as “loping-mode” or “skipping-mode.”  But sure, we can call it “bunny hopping” too.  So why did astronauts do this?

Well, there’s something about walking that most of us, in our daily lives, don’t realize: Earth’s gravity does some of the work for us.  When you take a step, first you lift your foot off the ground, then you extend your leg, and then… well, try to stop yourself at this point.  With your leg extended forward like that, you’ll find that your center of gravity has shifted, and you can feel the force of gravity trying to pull you through the remainder of your walk cycle.

So walking feels like a natural and efficient way for us humans to get around because Earth’s gravity helps us.  Take Earth’s gravity away, and walking suddenly feels awkward and cumbersome.  In lunar gravity, which is approximately ⅙ of Earth’s gravity, the Apollo astronauts found other methods of locomotion to be more comfortable, more natural.  In this clip, we hear audio chatter of astronauts disagreeing about whether “hopping” or “loping” is a better way to get around.

Personal preference seems to be important here, both in how astronauts “walked” on the Moon and in how they described the experience of this new kind of “walking.”

Getting back to the new spacesuits from NASA, the new design features a dramatically improved range of motion.  The next astronauts on the Moon will have a much easier time getting around, and according to Administrator Bridenstine there will be no need for bunny hopping.  “Now we’re going to be able to walk on the surface of the Moon, which is very different from the suits of the past.”

And that’s got me confused.  I’m really not sure what Bridenstine means by that statement because, as I just explained, it was the Moon’s gravity—more so than the spacesuits—that made Apollo era astronauts feel the need to “bunny hop” on the Moon.  The new spacesuits, with their improved range of motion, should help astronauts in the new Artemis program avoid gaffs like these…

But without altering the Moon’s gravity, I don’t see any way to avoid “bunny hopping.”

LIGO: The Next Generation

As everyone knows, I’m a total surfer dude.  So after all my recent blog posts about the LIGO project (click here, here, or here), I’ve been wondering: could I “hang ten” on a gravitational wave?

There’s still a lot we don’t know about gravitational waves.  LIGO—the Laser Interferometer Gravitational-wave Observatory—is one of the most delicately sensitive scientific instruments ever built.  But as sensitive as LIGO is, it’s still not sensitive enough.  The next generation of gravitational wave detectors promises to do better.

  • Cosmic Explorer: The United States wants to build a bigger LIGO.  Cosmic Explorer will use the same L-shaped interferometer design as LIGO, only ten times bigger.  This will increase the signal amplitude without adding to the amount of background noise the detector picks up, according to the Cosmic Explorer website.  Click here to learn more.
  • Einstein Telescope: Meanwhile the Europeans are planning to build a gravitational wave detector underground.  The Einstein Telescope, as the project is named, will incorporate not one but two laser interferometers, arranged in a triangular pattern.  One of these interferometers will pick up low frequency gravitational waves; the other will pick up waves of higher frequencies.  Click here to learn more.
  • LISA: And lastly, NASA wants to put a gravitational wave detector in space.  The project is called LISA, which stands for Laser Interferometer Space Antenna.  LISA will consist of three small spacecraft beaming lasers at each other, forming a giant equilateral triangle.  Size really does matter when it comes to gravitational wave detectors, and this space laser triangle will be far, far larger than anything we could have built here on the ground.  Click here to learn more.

Some of the questions these next generation gravitational wave detectors could help us answer: How many black holes are there in the universe?  What’s going on inside neutron stars?  What about pulsars or magnetars?  Are there gravitational waves associated with the cosmic microwave background?  Are there gravitational waves associated with dark matter?  Are any gravitational waves coming from unexpected or unknown sources?

So much science will be gained from these projects!  However, I’m not sure if Cosmic Explorer, the Einstein Telescope, or LISA will be able to answer the question I asked at the beginning of this post.  Total bummer!

Disclaimer: I’m not really a surfer dude.  Actually, I’m terrified of the ocean and I’ve never even learned how to swim.

Sciency Words: Entomopters

Sciency Words: (proper noun) a special series here on Planet Pailly focusing on the definitions and etymologies of science or science-related terms.  Today’s Sciency Word is:

ENTOMOPTERS

It is aerodynamically impossible for insects to fly, or so French entomologist Antoine Magnan famously claimed in 1934.  And it’s true.  If aerodynamics means the scientific principles governing the flight of airplanes, then you will have a very hard time explaining how insects fly using aerodynamics alone.

Do you know what else is aerodynamically impossible, or at least aerodynamically very, very difficult?  Flying on Mars.  The atmosphere is too thin for fixed-wing aircraft.  But perhaps where traditional aerodynamics fails, insect aerodynamics might succeed!

At least that was the thought behind the entomopter, a project proposed by Robert Michelson and colleagues at the Georgia Tech Research Institute back in the early 2000’s.  The term entomopter comes from two Greek words—entoma, meaning insect, and pteron, meaning wing.  So an entomopter is a flying machine that mimics the “aerodynamically impossibly” flight of insects.

As Michelson explains in this article:

Aerodynamic analyses of [insect] flight consistently revealed that their wings must produce 2-3 times more lift than conventional wings, and in some cases up to 6-7 times.  The extra load-lifting capacity this would offer Entomopters is highly significant, and indicates that a novel design based on flapping insect flight would outperform a more traditional aerodynamic approach.

The prototype entomopter built by Michelson and his research team was modeled after the hawk moth (scientific name Manduca sexta).  With a ten-centimeter wingspan, the hawk moth is an unusually large insect, which makes it easier to observe and study the movements of its wings. And I have to admit in this concept video from NASA, there is something distinctly moth-y about the way the entomopter flies.

I first learned about the entomopter while researching last week’s post on NASA’s NIAC program.  The entomopter was one of those so-crazy-it-might-work proposals that won grant money through NIAC.

You may have heard about the Mars Helicopter Scout (a.k.a. Marscopter), which will be accompanying NASA’s next Mars rover.  You may have also heard about Dragonfly, the robotic quadcopter that NASA plans to send to Titan sometime in the 2030’s. Neither of these spacecraft qualify as entomopters, and I’m really not sure how much thanks either Marscopter or Dragonfly owe to the entomopter project.  But I strongly suspect there is some sort of connection there.

Sciency Words: NIAC

Sciency Words: (proper noun) a special series here on Planet Pailly focusing on the definitions and etymologies of science or science-related terms.  Today’s Sciency Word is:

NIAC

Every once in a while, you’ll hear that NASA is working on some crazy Sci-Fi technology.  Space elevators, warp drive… stuff like that.  How seriously should you take this?  Well, I’m not sure, but NASA does have this special program called NIAC.

When NIAC was first created in 1998, the acronym stood for “NASA Institute for Advanced Concepts.”  The program was canceled for budgetary reasons in 2007, but then it was revived in 2011.  The acronym now stands for “NASA Innovative Advanced Concepts.”

As explained in a recent article from Scientific American, “The program functions as NASA’a venture capital arm, in that it supports technologies that might pan out, big-time.”  Basically, if you have a proposal for some highly speculative new space technology—something that sounds a little bit crazy, but not too crazy—NASA might give you grant money for your research.

NIAC funding has gone toward space elevators and robotic space bees.  A mission to Proxima Centauri using tiny “chip” sized space probes?  That got NIAC funding.  The almost magical sounding Mach effect thruster—a propulsion system that uses zero propellant?  That got NIAC funding.

Some of these ideas have been ridiculed by the scientific community and in the popular press.  And I have to agree: this stuff really does sound crazy.  But remember, The New York Times once ridiculed Robert Goddard for his crazy idea that rockets could get us to the Moon.  The New York Times was really harsh in their criticism.

But as we now know, Goddard was right, and The New York Times famously published an apology in 1969, just days before Apollo 11 landed on the Moon.

Most NIAC-funded projects probably won’t work out; but imagine what would happen if a few of them did!  So the next time you hear that NASA is working on some crazy sounding Sci-Fi tech, that probably just means somebody won a NIAC grant. I’m still not sure how seriously you or I should take these NIAC-funded projects, but maybe it’s okay to take them just a little bit seriously.