The strange history of named exoplanets

Of the 6,000 confirmed exoplanets, almost all of them are known by designations. A designation is essentially its scientific name, the long string of letters and numbers you're probably familiar with. People often complain about exoplanet names, and the names of space objects in general, as they're bad. And that makes sense when there are planets named things like PSR J1719-1438b or OGLE 2005 BLG390Lb. But the thing is, astronomers themselves also know these names are bad and are doing things Which is where the International Astronomical Union comes in. The IAU is an international body made up of 85 countries that has the final authority on names for astronomical objects, for convenience and to make sure all astronomers worldwide can have one name to refer to one object to avoid confusion. The IAU is the reason you know the star Betelgeuse as Betelgeuse, instead of Alpha Orionis or HD 39801 or HIP 27989 or the whole host of other names it has, just as one example. When people first started discovering planets outside the solar system, one of the first questions was how they should be named. And for a while, everyone had different ideas, until the IAU stepped in and created Name Exoworlds, which is basically a global competition held every few years that allows the public to officially name exoplanets. But Name Exoworlds is, honestly, really weird for the IAU. For some reason, exoplanet names are almost never used by astronomers, even though those same astronomers use the official names of asteroids and dwarf planets, like Mani, which was originally called 2002 MS4 before being given an official name a few months ago. As soon as Mani was named, the entire astronomical community immediately switched to using that name, but this doesn't happen for exoplanets. You probably still know the planet Jansen as 55 Cancri e, despite the fact that it was Personally, I believe that every exoplanet can and should be given a good name instead of a designation, and I'll elaborate on that more throughout the video, but I was inspired to make this after trying to see why exoplanet names are ignored, while literally every other type of astronomical object in the universe gets widely accepted popular names. And the story is actually pretty interesting. If a few things had gone a bit differently, the official names of exoplanets would probably be a lot more popular than they are today. So let's start at the beginning with one of the first ever exoplanets, Domitium, which you might know as 51 Pegasi b. It's pretty important, being the first hot Jupiter ever found, the first exoplanet around a sun-like star, the first confirmed gas giant outside the solar system, and for this video, the first exoplanet to be given a nickname. One of the people who confirmed the existence of Domitium, Jeffrey Marcy, decided to call it Bellerophon. And to be honest, a more perfect name could not exist. Bellerophon was a mythological figure who rode the Pegasus, which makes sense because Domitium is in that constellation. Bellerophon tried to fly to Mount Olympus, but was struck down. Domitium, the planet, is extremely close to its star Helvetius, but stopped spiraling inward and became a hot Jupiter. I love names that have layers of meaning, and Bellerophon was a great name. And people actually used that name. News sites called this planet Bellerophon at the time. It was well on its way to becoming a widely accepted popular name, if a nickname and not an official one. Unfortunately, Jeffrey Marcy was found to be in violation of his university's sexual assault policies. Due to this, many things associated with him, including the name Bellerophon, fell out of popularity. This was a major stain on the naming of exoplanets, so people mostly stopped giving them nicknames, especially as more and more were found. But there are still a few exoplanet nicknames that remain. The planet HD 209458b, which is unique for apparently being the first exoplanet to ever have a single thing known about it, is sometimes referred to as Osiris to this day, and the planet PSR B1620-26b has a widely used nickname that's even used by NASA itself, Methuselah. Osiris and Methuselah aren't the official names for either of these planets, but in the case of Methuselah, most people who have heard of this planet know that name or even use it. Ironically, the unofficial nickname Methuselah is more popular and used more often than any of the official names for exoplanets. There's also one more nickname worth mentioning, that being Zarmina's World, or just Zarmina, for the planet Gliese 581g. Stephen Vogt, one of the discoverers of this planet, chose to name it after his wife. This wasn't an officially recognized name, but it doesn't really matter because Gliese 581g doesn't actually exist. It was later found to be a false positive, and the Zarmina's World nickname fell out of use entirely, even though for some reason there are still clickbait videos made about Gliese 581g, which, again, does not exist to this day. That's probably because Stephen Vogt said it had a 100% chance of supporting life, but whatever. Anyways, those are the four most popular exoplanet names before 2015, Bellerophon, Osiris, Methuselah, and Zarmina's World, for 51 Pegasi b, HD 209458 b, PSR B1620-26 b, and the non-existing Gliese 581g, respectively. During this time, there were also a few websites saying people could pay money to name an exoplanet, most notably Uwingu, which tried to name a planet we now know probably doesn't exist, Alpha Centauri bb. They charged people $5 to submit a potential name, and $1 to vote on what name they thought was best. Though I should mention that this wasn't entirely just a cash grab, and that money did go to funding scientific outreach. Interestingly, this was actively supported and endorsed by one of the main astronomers who discovered Alpha Centauri bb, but it never went anywhere because Alpha Centauri bb was later found to also not exist. In 2013, the IAU decided it was time to make some exoplanet names official, and created a set of rules for what would eventually become the Name Exoworlds competition. Name Exoworlds is extremely similar to the other naming competitions the IAU or other astronomy organizations hold, often for asteroids and dwarf planets. The asteroid Bennu was named by a 9 year old in a competition like this. They created a set of rules, including adopting all the current rules for naming asteroids in the solar system, the proposals of a name can't ask for any money from anyone, and most interestingly, a name proposal must, quote, guarantee a wide international participation. The names must also be approved by the discoverers of the planet in question, and can't be named after military figures, be more than 16 characters, they must be pronounceable in some languages, and can't be offensive. It was also possible for people who met these rules to write to the IAU directly with their name proposals, independent of any public competition, for many different exoplanets. Interestingly, there was actually a lot of criticism about this, because the IAU was very vague on the naming rules. For example, it explicitly bans the names of individuals, places, or events principally known for political or military activities. The planet Mars is named after the Roman god of war. Would Mars be an illegal planet name under this rule set? This was also a reversal in the IAU's opinions about letting the public name space objects, as many people thought they were against it previously. And it came as somewhat of a surprise, because as recently as a few months before this announcement, the IAU said they weren't going to be naming exoplanets at all. So with a confusing rule set and a confusing announcement, you can see why many astronomers didn't take it too seriously. Especially because, as we're about to see, these rules were frequently broken. In 2015, the IAU created the first public name exoworlds contest. 32 exoplanets around 20 stars were to be named. However, in the end, only 31 exoplanets around 19 stars actually got a name. The exoplanet Taubu Otis B's results were voided and it never got named, because the winning suggestion broke the rules. Essentially, anyone could suggest a name so long as they followed all the rules, and the public was allowed to vote on what names they thought were best, and the IAU was able to remove spam name suggestions. And the results were interesting, to say the least. Of the 31 planets that were named, you've probably heard of many of them. 51 Pegasite B, the entire 55 Cancri and PSR B1257-12 systems, Upsilon Andromedae, Muare, and many others. Each of these planets were significant and deserving of names in their own way. The first exoplanets ever found, the first habitable zone planets, the first multi-planet system, there were several exoplanet firsts in this competition. I'm not going to go over all of the chosen names, but the whole list of named exoplanets will be in the pinned comment. Let's just go over some of the highlights. 51 Pegasite B was officially named Dimidium, the latin word for half, because it's half the mass of Jupiter. A massive step down from Bolerophon, but when you see the other suggestions, it makes sense. Other proposed names for Dimidium, after spam was removed, included Neil, after Neil Armstrong, Dot, Hydrogen, Tortoise, and Carousel Hell B. For Pollux B, the name Thestius was chosen, despite the fact that the winning name was Leda, because Leda was already the name of an asteroid. But that didn't stop Iota Draconis B from being named Hypatia, even though there's already an asteroid named Hypatia as well. I made a full video about this one, but 42 Draconis B was named Orbitar, a name that breaks at least 3 separate IAU rules at once, but it was somehow made official and approved. Some names didn't have any relation to one another, which was another IAU rule. The systems needed to have a common naming theme between the star and planets. 51 Pegasite was named Helvetios, after a Celtic tribe, which has nothing to do with the word Dimidium, or even the latin world in general. Fomalhaut B, which was named Dagon, wasn't even a planet, and turned out to just be a dust cloud. Orbitar doesn't exist either, which is a good thing. I could go on. Name ExoWorlds 2015 was, from the best I can tell, a mess. Combined with the controversy it was already in, I can see why people didn't take it seriously. A significant number of the 31 named exoplanets had names that broke the rules the IAU established, and they were somehow approved, and even after that, the planets that turned out to later not exist were named. Thestias, as well as two other gas giants named in 2015, Spey and Arcus, also have evidence against them but aren't totally disproven yet. However, some good did come out of it. PSR B1257-12 got the names Lich, Draugr, Poltergeist, and Phobetor, which follow all the rules and are actually good names. These names have even become decently popular among the public, often replacing their designation. Most of the names were good like this. Tadmor, Smertrius, Eiger, Saffar, Sama, Majrity, Jansen, most of the names were fine. There was definitely a good amount of problems, but at the end of the day, we got 31 named exoplanets. Except for Taobu Otis B. I don't really understand why the IAU banished all of its potential names to the Shadow Realm when they let Orbitar get through, but maybe there was a good reason. Anyways, four years later, the IAU decides to give it another go for their 100th anniversary of existing and create NameXO Worlds 2019. New 2019 was extremely different from the competition that came before it. Instead of 31 planets, a total of 113 exoplanets were named. This is because the IAU assigned an exoplanet to every country on Earth and told them to give it a name, and most did. However, the exoplanets that were chosen were different from last time. Instead of choosing globally significant exoplanets, the IAU gave every country a star and a planet that was visible in that country, and when possible, one that had some significance to that country, such as a scientist from there discovering it. However, every single one of them was a gas giant. This is because they wanted to be fair and give every country a similar planet. Though in reality, all of these planets were different. There were hot Jupiters, temperate gas and ice giants, a planet that seemingly survived inside a red giant star and came out alive, eccentric Jupiters, puffball planets, and the masses and orbits were all over the place. Also, Puerto Rico, Aruba, and the Cook and Picarin Islands were given planets for some reason. But the IAU was far better with getting the rules right this time, and there were some new ones this time around. If they wanted to name a planet after a person, that person has to have been dead for more than 100 years. They can't be acronyms, promote commercial products, be copyrighted, use punctuation, or be made up words like Orbitar. Also, names known for religious activities were banned, along with military and political names, which is weird. The planets Bendita, Wangshu, Ditso, Azye, Boinayel, Belisama, Ixbalanque, Zolotl, Hake, and Amatex were all named after gods, and that's not even including the several other planets that were named after mythological figures. However, I don't think this was against the rules, as it specifically bans religious activities, not religious figures. So I guess you can't name a planet going to church or whatever. Also, side note, I've definitely pronounced many of these names wrong, as I can't find reliable pronunciations for most of them. If anyone knows how to actually pronounce any of these names properly, tell me in the comments. Other than that, the only names that really broke the rules were Viriado, named after an ancient Lusitanian leader who fought the Romans, and Hayisi, which shares its name with an asteroid. Though Viriado is technically allowed because he's not principally known for military activities, it's just a thing he did on the side, I guess. Anyways, all these names were made official by the IAU, bringing our total count of officially named exoplanets up to 144. Only one of these planets was found not to be a planet, that being Tondra, which is actually a red dwarf star instead. So at least unlike Dagon and Orbitar, they did name an object that actually exists, it's just not a planet. Namexoworlds 2019 was criticized mostly for its large number of uninteresting planets. None of them are really significant except for some minor reason in a handful of countries. While the international outreach thing was cool, it was clear that the IAU probably needed to change things up. Which is where Namexoworlds 2022 comes in. The IAU finally decided to lock in and do a Namexoworlds correctly. 20 planets were chosen to be named, and they were all different from each other. Most were hot, but there were hot Jupiters, hot Neptunes, hot mini-Neptunes, and hot rocky planets. LHS 3844b, GJ367b, L168-9b, and GJ486b were the first rocky exoplanets to be named since 2015. And all of these planets had a reason for being named. They were some of the prime targets for James Webb to study, which at the time had only launched a few months ago. This time, the rules were stricter than ever. The names of people, living or dead, were completely banned. And names used for space objects, even ones not officially IAU-recognized, weren't allowed. For example, there's a star called Gakrux, meaning you can't name your planet Gakrux. However, you also can't name your planet Bunya, the name of Gakrux in another language. But luckily from what I can tell, for the first time ever, all of the rules were followed perfectly. From my look, I can't find any name that breaks the rules. All of these planets definitely exist and are definitely planets because they've all been looked at by James Webb. And we actually know things about them, and those characteristics were used to inspire their names. The planet GJ3470b, my personal favorite exoplanet, was named Pilenseum, a type of blue gemstone, because its atmosphere is suspected to be blue in color. GJ367b was named Tahe, a type of flower in Chile that only blooms for 8 hours, because its orbital period is 8 hours long. LTT9779b, the brightest known exoplanet, was named Quancoa, after an ancient, out-of-use name for Venus, the brightest planet in the solar system. Namexoworlds2022, at least in my opinion, finally brought credibility back to an exoplanet naming system that desperately needed it. I actually entered this competition myself and tried to name the planet WD0806-661b, but ultimately lost to the name Ara. It's now been 3 years since the end of New 2022, which means that we should be due for another Namexoworlds sometime soon. The Nancy Grace Roman Space Telescope is due for launch later this year, which will be used to study exoplanets, so that's a pretty good opportunity to launch Namexoworlds2026. But ultimately we'll have to wait and see. For now, there are 164 exoplanets with official names, out of the roughly 6,000. Again, the full list of that will be in the pinned comment. Before I end this video though, I do want to go over some other objections to naming exoplanets I've seen astronomers talk about and why I disagree with them. I believe that every object in space can and should be given a proper name, and designations should be for scientific use only, similar to the scientific names of animals. Names give an object a quality of relatability you can't get with a string of numbers and letters. I've seen this myself on my own videos. People are far more interested in the exoplanet Pilenseum than JJ3470b. I get the most comments about named exoplanets. Giving and, more importantly, using exoplanet names directly improves science communication, and it should happen a lot more often. Anyways, some objections. People say that there are too many planets in the universe to give them all a name. I've never understood this argument because names are reused all the time. There's several cities on Earth named London. Nobody gets confused because there's context. You say London, England, or you say the country of Poland rather than the city of Poland in Kiribati. Similarly, you can say Hypatia the exoplanet, or Hypatia the asteroid. If there's more than two Hypatias, then say Hypatia the gas giant, or the gas giant orbiting Edasich, or Hypatia the gas giant 101 light years away. There's absolutely no problem with reusing names. It doesn't lead to confusion, that's been proven on Earth. Also, this wouldn't be a problem for a very long time if ever, so there's no point in worrying about it now, we're not running out of names any time soon. I've seen astronomers say it will be hard to remember all the names. Well, it's hard to remember the designations as well, that's why exoplanet catalogs exist. We live in an age where there are websites listing every known exoplanet. Just search up the names, it only takes a few seconds and it's what I do. One of the biggest arguments in favor of keeping the designations is that the designations say useful information about the planet. For example, 55 Cancri e is the fourth planet discovered orbiting the star 55 Cancri, and you can tell that just by reading its name. But the thing is, the average space enthusiast doesn't know that. They don't see the designations like that, they see it as meaningless letters and numbers. I'm not saying that the designations should be gotten rid of, but I am saying that should be used in scientific settings only. When communicating with the public, the proper names should take priority, as it's easier to communicate and also makes these planets seem like actual worlds rather than data points in a file somewhere. Again, I've seen this with both my own channel and the astronomy communication I do outside of the internet. I'm not a terribly large creator, but I do think my audience is large enough to be somewhat representative of the general population of people interested in astronomy, and I keep track of what comments are saying just for myself. And people like officially named exoplanets better. It's just easier to follow. And I've done this in real life as well. It's a small step, but in this day and age, any idea that makes science communication easier is a good one, which is why I always use the proper names of exoplanets on this channel and will continue to do so. I have yet to see a good argument to do otherwise, and there are several benefits. Though I will say one thing I do agree with is that the most significant exoplanet should be named first. We don't need to name every random gas giant like in 2019, let's name the most scientifically important and interesting ones first, because those are the ones most talked about and thus the most deserving of a name. Of course, the problem with that is deciding what culture gets to name those planets. The Greeks and Romans already got the solar system, and it's not terribly fair to name, say, the first exoplanet with a chance of habitability after just one culture. I think we should find names that are representative of all of humanity. That's probably difficult though, and there aren't any names that come to mind for me. So the best thing to do is, in my opinion, just make it more known that there are officially named exoplanets. I love it when things have meaningful names and exoplanets are no different. The history of naming exoplanets has been pretty weird and filled with a lot of bumps, but I think things are looking up, and hopefully soon, these names fully come into common usage. Thank you for watching. If you enjoyed, check out my other videos about exoplanets and space exploration.