X-Planet? (astronomy series)

Park-N-Grab along East Greenland Rd.

Much has been made recently about Pluto’s status as a planet in our solar system. As it should be: Science has as much a place in the national discussion as say- American Idol, or Donald Trump’s antics- but it is often overlooked in the circus.

But not Pluto. Today we are going to spend a couple minutes learning about x-planets, and Planet X.

Yes, that’s planets, with an “S”. What? You thought Pluto was the only one to suffer such indignity? Nope!

First, a bit of definition. Pluto IS still a planet. A dwarf planet is a planet, in the same manner a micro cache is still a cache. But like the micros that make up the stages of a multi-cache, Pluto is a piece, or stage, of the larger picture: In this case, Neptune. Both Pluto, and the anti-Pluto, Orcus, resonate with Neptune’s orbit, much the same way the steps of a multi-cache “resonate” with the final. So no more tears over Pluto! Pluto is special, and we’ll see how special in a few paragraphs.

Let’s hearken back to the first day – or first night, of 1801. Sicilian monk, Giuseppe Piazzi, discovered Ceres, and the world celebrated the news. A new planet had been discovered between the orbits of Mars and Jupiter! Soon Ceres joined the mnemonics children were memorizing in school- My Very Excellent Mother Can’t Just Send Grapes … wait, something is wrong…let’s see, Mercury, Venus, Earth, Mars, Ceres, Jupiter, Saturn, George, …oh, yeah! No Neptune or Pluto yet!

We had Ceres instead. And people loved our smallest planet, Ceres! She was named for the goddess of the grain (the same place we get the word “cereal” from: the 1800’s were big into grain). But wait a minute. In March of 1802, Wilhelm Olbers discovered another planet, Pallas Athena (Pallas for short), also in between mars and Jupiter. And then in 1804, Karl Harding had to jump on the planet bandwagon and discover Juno nearby. Which made Olbers feel all competitive, so he discovered Vesta in 1807.

Where were we. Oh! MVEMCPaJVSG…um… My Very Excellent Mother Can’t Paint Junior Varsity Socks and Underwear…no, no, wasn’t Uranus still called George then?…um… What a mess!

Four tiny planets between Mars and Jupiter. All of them small enough to look like a star in the telescope (Big planets really do look like discs in a good telescope, it’s the tiny guys that twinkle and otherwise look “starry”) Ten planets, and Neptune hadn’t even been discovered yet!

Sooo…. Labels changed. This happens in science: the facts don’t change, but our perception around those facts do. So Ceres, Pallas, Juno, Vesta, and Astraea (discovered in 1845) crowded the space between Mars and Jupiter. So the label on these planets changed to “asteroids”, and as more and more asteroids were discovered over time, the bru-hah-hah settled down.

Now what’s this about Planet X?

Back in 1781, Uranus never got called Planet X, because William Herschel wasn’t looking for a planet. He and his sister Caroline were doing a sky survey- noting where the stars were, and mapping them. Herschel discovered a comet, and made a notation in his journal, and brought it round to his friends and showed them. The friends looked for this comet in the night-time sky. It never showed any signs of having a tail. Or a coma. Or an irregular orbit. Or any of those cometty behaviors they were expecting. Around 1783 his astronomer friends got together and told him, “Hey, Hersch, this is a planet, name this thing already!”

So he did.

He named it George. Or Georgium Sidus (George’s Star) after King George 3^rd of England.

Outside England, the name never caught on. Other places called it Herschellium, after Herschel himself. An astronomer in Italy called it Neptune- for the British Naval Victory during the American Revolutionary War, which even I find confusing, and I used to be an explainer for a living.

Old records were looked at, and it was found that John Flamsteed had actually seen it, and marked it in his records as a star in Taurus.

They named it Uranus, from the Greek. Making it the only planet named for a Greek deity, rather than a Roman one. The last astronomical catalogue to hold out for the old name, Georgium Sidus, gave up in 1850, four years after Neptune was discovered.

With the discovery of George, astronomers knew something else was out there because George’s orbit would speed up and slow down oddly. That meant another planet had to be nearby. In 1849 Neptune was discovered, and named with far less controversy then George…errr… Uranus was. And they also found that Neptune had been recorded before being discovered- by Galileo in 1810. Using his new telescope he had made with instructions from Hans Lippershey (Galileo is often credited with the invention of the telescope, but Lippershey was a lens maker who may or may not have invented the telescope in 1608. Or it may have been his apprentice, or the neighborhood kids playing, or even another Dutch lens maker; the history is unclear on who DID invent it, but despite popular belief, it was not Galileo. Which is cool, because he did so many other spiffy things)

But then, there was a problem with Neptune. Its orbit also seemed to speed up and slow down. Rut roh! There must be another planet out there!

The search was on for the new planet, X.

http://en.wikipedia.org/wiki/Planets_beyond_Neptune

A Kansas farm-boy named Clyde Tombaugh discovered Planet X at the urging of Percival Lowell (who came up with the name “Planet-X”. They knew there was a planet there, and didn’t know what to call it, so until it got discovered and named, it was called X) There was some controversy over the name “Pluto” like there was with Uranus, (the symbol for Pluto looks like the letters PL, which is Percival Lowell’s initials) but that took less time to settle down than the 80 years it took for the Uranus controversy to settle down.

No, the problem with Pluto was its size. It was small, like an asteroid.

And its composition. It wasn’t rocky/volcanoey/atmospherey like Mercury, Venus, Earth or Mars. It wasn’t a ringed gas giant like Jupiter, Saturn, Uranus or Neptune. It didn’t have aurorae like planets with dynamic cores. Nope, it was a icy lump, like a comet, with a moon instead of a tail (to be fair, the other moons of Pluto weren’t discovered till much later)

And it has an orbit like a comet. All weird, and elliptical-like.

But Pluto took its place among the planets. And our Mnemonics, My Very Excellent Mother Just Sent Us Nine Pizzas. Easy to remember, and everybody loves Pluto Pizza!

So what exactly is a planet?

Is it a thing that goes around the Sun and has moon(s)? If that’s the case, then Venus and Mercury are not planets.

If it’s something that goes around the Sun, and is big enough to be spherical under its own gravity, has a differentiated crust, and has an atmosphere, then Titan, the largest moon of Saturn, is a planet, too. It also has clouds, and rain, and liquid methane at the surface- but it’s a moon.

If it’s cleared its orbit around the Sun, is it a planet? (this was one of the criteria used to “demote” Pluto.) Guess what? Earth isn’t a planet under that definition. Mercury would be the only planet if that’s the system we used.

Sun rises in the east, and a year is longer than a day? Uranus and Venus both fail: Uranus because of axial tilt, and Venus because she rotates backwards, and a single day on Venus is longer than a year, there.

So our very definition of “planet” is somewhat wibbly-wobbly. Also its subject to constant debate and refinement.

Which brings us back to Planet X. Pluto was X for awhile, until we named it Pluto. The next Planets we called X now have names like Quaoar, Sedna, Ixion and Varuna. Not to mention Orcus, Makemake, Haumea, and Eris. (In fact, Eris embraced her Planet-X-ness so hard that the scientists that discovered her even called her Xena for awhile) There could be dozens, if not hundreds, more.

They are all out there, icy worlds around Neptune and beyond. We call them “Trans Neptunian Objects”, or “Plutoids”, or “Kuyper Belt Objects”, or even “Cubewanos”. Some, like Makemake, Eris, and Haumea, are already classified as dwarf planets like Pluto is. Some may never be called planets at all. But what all these Planet Xs have in common, is they are all overshadowed by the healthy debate over Pluto.

Which can be good and bad- bad that Pluto gets all the attention, but good in that people are talking and thinking about science

To learn more about these dwarf planets, and dwarf planet wanna-bes, check out some of the links below.

Eris (codename Xena) http://en.wikipedia.org/wiki/Eris_%28dwarf_planet%29

Varuna http://en.wikipedia.org/wiki/20000_Varuna

Ixion http://en.wikipedia.org/wiki/28978_Ixion

Haumea (codename, Santa) http://www.spacedaily.com/reports/Haumea_Shines_with_Crystalline_Ice_999.html or http://en.wikipedia.org/wiki/Haumea_%28dwarf_planet%29

The red planetoid, Sedna http://www.spacedaily.com/reports/Case_Of_Sednas_Missing_Moon_Solved.html or http://en.wikipedia.org/wiki/90377_Sedna

Not a dwarf planet 1993-RO http://en.wikipedia.org/wiki/1993_RO

Quaoar http://en.wikipedia.org/wiki/50000_Quaoar

Makemake (codename Easterbunny) http://en.wikipedia.org/wiki/Makemake_%28dwarf_planet%29

And the anti-Pluto, Orcus http://en.wikipedia.org/wiki/90482_Orcus

I was ready to wrap up the cache info here, but a funny thing happened to me on the way to the Rapture. I met a man buying solar panels, and we struck up a conversation. Now, without going into Doomsday conspiracy theories, this gentleman spoke of another Planet-X. The planet he was talking about he called Nibiru (other people call it Nemesis, and others Marduk- but it can’t be Marduk because there is a Star named Marduk, and it can’t be called Nemesis, because another conspiracy theory has a star named Nemesis that is supposed to be the binary to our Sun, and that would be way too confusing...Well, maybe not so much; there are 5 stars named “Deneb”, or variations thereof. Denebola, Deneb- it just means “tail”. And one star that has at least twenty names- my favorite being Cynosure. But I digress). So if you run into any UFO abductee-types talking about Planet-X, this is what they mean, while the rest of us mean real celestial bodies like Plutoids and Cubewanos. As for Nibiru, I am not going to dignify it with a link. If you are interested, feel free to web search it. And if you want to survive an asteroid/planet/comet strike to the Earth, a couple solar panels (or buying gold, for that matter) is not going to cut it. Survivability means having an active, engaged, and fully-staffed space program; we are part-way there with the ISS, but we need one that can host a seed-bank/embryo-bank on the moon or elsewhere in case of catastrophe- like a technological Noah’s Ark. Anything less is just putting a skunk in the oven and calling it “Biscuits”. But I digrees

Whew!

Cache is a cammoed film canister- a dwarf cache, like Pluto! Bring a pen