A mistake made during the Apollo 11 moon landing could have brought lunar germs to the Earth, astronauts have revealed. When the three astronauts flew to the Moon and back, exactly 50 years ago this month, NASA worked hard to ensure that no bugs were brought back from the lunar surface. All three of the Apollo 11 crew were put into special clothes, scrubbed down and taken to a quarantine facility where they lived until scientists could be sure the Earth would not be contaminated. But interviews from a new documentary -- filmed by PBS and revealed by Space.com -- show that the plan to keep Earth could easily have failed, and that space bugs could have got into the Earth's atmosphere despite Nasa's best efforts. The astronauts noted that Nasa did not think there would be anything alive on the Moon that could be brought back down to the Earth. But the precautions were taken in case there were.
"Look at it this way," astronaut Michael Collins said. "Suppose there were germs on the moon. There are germs on the moon, we come back, the command module is full of lunar germs. The command module lands in the Pacific Ocean, and what do they do? Open the hatch. You got to open the hatch! All the damn germs come out!"Regarding Viruses there is a a science about them . (1)>>BIG question , just what are they? A virus is a small parasite that cannot reproduce by itself. Once it infects a susceptible cell, however, a virus can direct the cell machinery to produce more viruses. Most viruses have either RNA or DNA as their genetic material. The nucleic acid may be single- or double-stranded. The entire infectious virus particle, called a virion, consists of the nucleic acid and an outer shell of protein. The simplest viruses contain only enough RNA or DNA to encode four proteins. The most complex can encode 100 – 200 proteins. It's impossible to know with certainty just how many types of viruses exist in the natural world, with numbers climbing as researchers use new tools to search for classified and unknown genetic signatures in the soil, oceans, and even the skies. Rough estimates suggest there could be as many as 100 million types of
virus on Earth's surface. We know of Earth based Viruses . (2)>>How about those from Outer Space ? Statistical data show that sometime after the passage of the Earth along its orbit through the tail of a comet, a number of epidemics and pandemics occurred. This indicated a possible invasion of viruses, which could be in cometary dust. K.I. Churyumov proposed to develop special traps. They need to be placed under the wings of high-altitude aircraft. And with their help it is necessary to catch, accumulate and examine in the laboratories those particles, which are captured in traces of invasions. The main purpose of such experiments is to reveal, or prove the absence of cosmic viruses in the tracks from the intrusions of fragments of cometary nuclei. Viruses are mentioned six times in NASA's 250-page-long current astrobiology strategy, write the authors of a recent paper called "Astrovirology: Viruses at Large in the Universe." They call for the study of viruses to be incorporated into extraterrestrial science missions and astrobiological research at home, and have a checklist for the actions needed to put viruses on the interplanetary map. Virions, on the other hand, are the viral seeds that could become viruses if they happen upon compatible living cells in which to replicate. On Earth, virions and viruses go hand-in-hand with life, and if we find the former on other planets, they could point to cellular life once having existed on them. Evidence of organic molecules such as pieces of RNA, DNA, and proteins have been found on recent meteorites. This demonstrates that (3)>>space already has the conditions to allow for these chemical reactions to take place beyond Earth. The authors suggest that the beginning of life must have been simple, and the search for signatures of viruses, viroids, and small RNA and the modeling of these “life forms” may be where we need to turn our attention next to answer the questions about life in our Universe.
Planets that "might" have Viruses.
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Could the acid clouds of the Planet Venus
be hiding Viruses ?
Could they travel to Earth? |
A number of scientists have hypothesized that Earth may be seeding this solar system, including Venus, Mars, and the Moons of Jupiter and Saturn, with microbes buried within ejecta following impact by comets and meteors. How often or how much of this atmospheric biota is lofted into space, is unknown. However, under extreme conditions, and if solar winds strike with sufficient force, then water molecules, surface dust , along with air-borne bacteria, spores, fungi, lichens, algae, and other microbes may be ejected into space , where, as demonstrated experimentally, this biota may easily survive . We’ve heard about the possibility of extraterrestrial life arriving on Earth from another planet, asteroid or comet, but the mode of transport usually includes a chunk of rock falling through the atmosphere as a meteorite. But there could be another form of interplanetary transportation. What if there are (4)>>microbial forms of alien life floating in the upper atmosphere of Venus (the planet’s clouds contain compounds that could indicate presence of micro organisms)? Could they make the trip to Earth? Apparently it is possible, if Earth and Venus are correctly aligned, the solar wind may carry microbes from the upstream Venus to downstream Earth in a matter of days…This may be the case for Mars, although it remains to be seen whether life did ever exist in the brief warm and wet periods of the red planet’s ancient history. Let us suppose
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Mars has all the elements for Viruses
Water . |
that (5)>>Mars did once harbor primitive microbial life, with the requisite viruses accompanying it. As we have seen, on Earth most viruses are host specific –the same would hold for extraterrestrial viruses too. However, when Martian life died off, or at least became rare, viruses would have been faced with a problem. If they remained host specific, they would disappear along with their hosts. If, however, the adapted and became generalized they could inhabit whatever cells they came across, sharing genetic information to survive at a subsistence level.As such, if there was once life on Mars, today all that may be left could be the generalized viruses, capable of infecting most cells they come across. These viruses could therefore present a biohazard for any future astronauts that land on Mars and perhaps while we are looking for life on Mars, we should also equip our robotic rovers to search for viruses too. NASA and the European Space Agency plan to haul pristine Mars samples to Earth in the near future, perhaps in the 2030s. Receiving pieces of the Red Planet in this way is deemed to pose a low risk to ecological and public safety — but that risk is not zero. The Mars samples, which will be collected and cached by NASA's Perseverance rover, could end up being biological "hot property." And the material might spark heated debate and public anxiety about creepy-crawlies from Mars chomping away at Earth's biosphere. (6)>>The NEXT place that could have viruses are COMETS . If passing comets have continued to deposit viruses and microorganisms on this planet, this may explain why ancient astronomers and civilizations attributed the periodic outbreak of plague to these stellar objects. Moreover, the subsequent evolution and extinction of life may have been directly impacted by the continued arrival of bacteria, archae, viruses, and their genes from
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Comets have Carbon and Water Ices
they could be a nest full
of viruses. |
space. On this picture the evolution of higher plants and animals, including humans, would be impacted by the insertion of genes from space, as well as recurrent episodes of pandemic disease. Near-culling pandemics and extinction episodes have in fact been preceded by or followed by inserts of viral genes into survivors who have transmitted these viral elements to their progeny, thereby impacting future evolution. Although ancient fears and reverence of comets may be coincidental with the outbreaks of pandemics, they may also have a factual basis.Ancient Chinese astronomers chronicled numerous episodes where the apparition of comets preceded plague and disaster. Meticulous observations were compiled in 300 BC in a series of books known as the "Mawangdui Silk" (Ling-feng 1976) It details 29 different cometary forms and the various disasters associated with them, dating as far back as 1500 B.C: "Comets are vile stars. Every time they appear in the south, they wipe out the old and establish the new. Fish grow sick, crops fail, Emperors and common people die, and men go to war. The people hate life and don't even want to speak of it." -Li Ch'un Feng, Director, Chinese Imperial Astronomical Bureau, (648, A.D). And the prospect of moon germs also mirrored a real public health concern at the time, of novel pathogens that the population had never had a chance to build an immunity to. It's a fear that remains with us today, which was sparked at the time by, for example, new influenza strains popping up on occasion. If something nasty hitched a ride back from the moon, it would have been the epitome of a novel pathogen. And, it would have driven doctors and public health practitioners way beyond their comfort zone. Before Apollo 11 set out, NASA couldn't be positive that, if bits of dust or potential microorganisms got loose back home, life on Earth would be safe. Needless to say, accidentally setting a lunar plague loose on the inhabitants of
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Oddly Lunar Dust could be a biohazard
to future Astro Explorers . |
Earth would have erased all the good publicity garnered by accomplishing the moon landing in the first place. Just in case, in addition to the protections they were establishing to make sure the moon rocks remained free of terrestrial contamination, NASA decided to establish a three-week quarantine for the crew of Apollo 11. The lifeless and sterile moon could also offer an ideal proving ground for “synthetic biology” experiments before they could be unleashed elsewhere in the solar system. The trouble with moon dust stems from the strange properties of lunar soil. The powdery grey dirt is formed by micrometeorite impacts which pulverize local rocks into fine particles. The energy from these collisions melts the dirt into vapor that cools and condenses on soil particles, coating them in a glassy shell. Lunar dust, being a compound of silicon as is quartz, is (to our current knowledge) also not poisonous. But like the quartz dust in the Hawk's Nest Tunnel, it is extremely fine and abrasive, almost like powdered glass. Astronauts on several Apollo missions found that it clung to everything and was almost impossible to remove; once tracked inside the Lunar Module, some of it easily became airborne, irritating lungs and eyes. Right: Microscopic images of moondust. [More ] NOW the Outer Solar System has a few places to visit if you want to pick up a good virus . SATURN'S LARGEST MOON TITAN could be next place beyond Mars in finding exotic life.Larger than both our own moon and the planet Mercury, Titan is unique in our solar
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Saturn with it's Mysterious Moon
Titan . |
system. Aside from (7)>>Enceladus is an active moon that hides a global ocean of liquid salty water beneath its crust. Titan is the only moon with clouds and a dense atmosphere of nitrogen and methane, which gives it a fuzzy orange appearance. (7.1)>>To LOOK AT TITAN at what it's got going on: hydrocarbon lakes, frozen icy crust, an atmosphere as thick as a planet'sTo date only one measly probe, the Cassini mission, was sent to investigate the Saturnian system in detail, and it dropped off the Huygens probe for a short-lived and suicidal but scientifically useful mission to the surface of Titan. In the coming decades, both NASA and the European Space Agency are planning audacious missions (involving quadcopters and rovers and other seemingly-sci-fi awesomeness) to study Titan. What do they hope to learn? Read on to find out some of Titan's biggest mysteries. Many scientists believe that Titan could host life due to its environmental conditions. It is the only moon in the Solar System to have a dense atmosphere, which increases its chances of having pools of liquid water. According to previous scientific studies, the pools on Titan are filled with frigid lakes of hydrocarbons. Although these pools might be extremely toxic, scientists believe they could still support microbial life due to the presence of nitrogen-based molecules known as azotosomes. Theoretically, these molecules could arrange themselves to form bubble-like membranes around the cells of a living organism. This idea is based on how lipid molecules function on Earth. Organic materials - carbon-based compounds critical for fostering living organisms - play a leading role on Titan. On Earth, water rains down from clouds and fills rivers, lakes and oceans. On Titan, clouds spew hydrocarbons like methane and ethane - which are gases on Earth - in liquid form due to the moon’s frigid climate. (8)>>If we turn to the possibility of life based on another liquid, each of these background assumptions must be reexamined. The only other world we know that has a liquid on its surface is Titan, where we find liquids of methane and ethane. Titan is the largest moon of the planet Saturn but is small compared to Earth, with a surface gravity 1/7 that of Earth. Its
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Titan the Orange Mysterious world
it's hazy , but it might truly hide
alien life. |
surface atmospheric pressure is about 1.5 times that of Earth, and the surface temperature is 95 K. The atmosphere is dominated by N2 (95%) with CH4 (5%) and H2 (0.1%) and various trace organic compounds. The lower atmosphere has an active hydrological cycle of liquid methane, including convective clouds and rain, both of which vary with the seasons. Titan is locked in a synchronous orbit around Saturn with a period of 16 days (the cycle of light and dark). The tilt of Saturn’s spin axis to its orbit plane is ~27°, resulting in seasonal changes in the position of the sun in Titan’s sky over the ~30-year period of Saturn’s orbit. The lower atmosphere of Titan is too thick to respond to the 16-day light-dark cycle but does respond on the 30-year seasonal timescale. Thick convective clouds congregate in the summer polar region.Photochemical reactions beginning with the dissociation of the atmospheric N2 and CH4 create an array of organic molecules in Titan’s atmosphere and produce a solid organic haze in the upper atmosphere that obscures the lower atmosphere and surface. The organic haze particles eventually settle on the surface. A major product of the photochemistry is ethane, which accumulates on the surface and mixes with liquid methane. There are large lakes of methane and ethane on Titan, ranging in size up to ~1000 km across. Observations of the Huygens lander indicated moisture (methane and ethane) in the ground at the landing site. It appears that liquid methane and ethane are widespread and actively cycled on Titan. Is a “follow the methane” strategy plausible? Beyond the Planet Saturn , we pass the ICE GIANTS named (9)>>URANUS and NEPTUNE with huge possibilities of viruses , and alien biota . These world are 2 to 3 billion miles from the Earth , the Sun . These worlds are at the outer edge of the solar system , where the sun light is at the weakest . That far from the Sun the tempretures run nearly close to 400 below zero . ANY place as we travel farter from the SUN is our last stop in our SOLAR SYSTEM . we find (10)>>THE DWARF PLANET PLUTO . And perhaps the strangest place to find any kind of virus existing . For now, astronomers presume life is most likely on planets that, like Earth (the only place where life is proven to exist), orbit in a “not too cold, not too hot” orbit cutely named the “Goldilocks zone.” This new research could widen the net. Pluto is thought to be too cold and too old for liquid oceans, its age meaning that any oceans would have frozen long ago. The scientists think that there could be an insulating layer of gas that could be keeping an ocean in liquid form. Pluto is on average 40 times further from the Sun than Earth is, with sunlight taking around 5.5 hours to reach it. It receives just 1/1600 of the sunlight that Earth gets and its surface at the equator can get as cold as −240 °C/−400 °F. The chances of life existing on Pluto, and what form it might take, would depend largely on what the ocean itself is made of, and that’s still a subject for debate. Pluto’s subsurface ocean remains hypothetical at this point. All of these ideas about an ocean inside Pluto are credible. Even at that Pluto could be a home with virion's existing in the below surface ocean of exotic liquids that can only thrive in a really alien enviroment.
What is Above is Below .
One of the biggest killers on our planet is disease, easily spread, and as of yet we've seen years of influenza evolving to counteract anti-biotics. There's a thought that some diseases (even the flu) came from space to our planet, and used it like a petri dish to incubate. So when space travel does become a thing, what new pathogens are we planning to attain when we go to another planet? Just like the Mayans were introduced to smallpox, we're subjecting ourselves to an entire planet of infection, assuming it's already developed the way our beautiful Earth has. How are we going to survive? Some of the first non-Earth colonizers are definitely going to be suited up and have lots of disinfectants to try to combat a problem like this. We managed to go to the moon with no one dying from Space AIDS, so the possibility is always present. I guess another thing to consider might be giving travelers to Mars a big dose of a wide spectrum of antibiotics prior to travel... thereby hopefully eliminating yet more additional diseases brought to Mars. But I'm not sure even that would eliminate us bringing something like E-coli to Mars.But nevertheless... yes: A LOT of diseases can indeed be filtered out, and left behind on Earth forever, never to bother us again... if we plan the future Martian colonies very carefully, and make sure we don't transport anyone carrying significant disease causing viruses or bacteria. As for encountering new diseases in space, the chances of that are nearly zero (nil), based upon current information we have.That is because there is absolutely NO EVIDENCE to date that extra terrestrial life exists anywhere in the near galactic neighborhood, let alone our solar system. Also, whoever told you that the flu came from outer space has been watching too many SciFi and Twilight Zone episodes!
NOTES AND COMMENTS:
(1)>>BIG question , just what are they? If viruses are alive, they will acquire taxonomic status and the term "virus" will have taxonomic value. It would thus not be possible to use it for comparable extraterrestrial virus-like things without implying common descent and taxonomic affiliation (hence the reference to panspermia - you'd have to explain how organisms with a common line of descent exist both on, and away, from Earth). If they are merely similar without beeing homologous, it would simply be convergent evolution without common descent and they would have to be called something else.If on the other hand they are not alive, then the term "virus" would become merely descriptive and refer to a specific type of chemical and molecular organisation which would have to be precisely defined taking into account the particularities of the newly found dingusses. The extraterrestrial things would then either meet those criteria exactly and be bona-fide virusses, or they wouldn't in which case another term would be required.In the interim, the term virus-like would have to do. (2)>>How about those from Outer Space ? In the article Influenza From Space? Sir Fred Hoyle and Chandra Wickramasinghe carry on a dialog with critics about comet tail delivery systems for extraterrestrial biological visitors. This would be consistent with the idea of panspermia, or life from outer space. These researchers found evidence which suggests that influenza (at least in the beginning of a given flu season) breaks out in a sporadic manner, but doesn't spread easily. This is not unlike Kolata's reported "hopscotching" effect. [Link removed to no longer existent page. 19 Jan 2007] Though not visible to the naked eye, the planet Venus has a comet-like tail that solar system scientists have been studying for years to gain improved insights into the nature of comets. (Most of this information is in hard copy and I don't currently have any references.) In their extensive on-line reprint of an article titled The Interaction of the Solar Wind with Venus C. T. Russell and O. Vaisberg suggest that "On the whole, the solar wind interaction with Venus is more comet-like than Earth-like." http://www.panspermia.org/panfluenza.htm Barber reported "Following the 1937 outbreak, [at Lockyer Observatory] water samples were sent to the bacteriological department of the Seale-Hayne College, Newton Abbot, and tissue cultures were obtained. It was, however, found to be impossible to match these with any known strains of indigenous liquefying bacteria. The result was later independently confirmed by tests carried out at the Lister Institute." http://www-ssc.igpp.ucla.edu/personn...eract_solwind/ Food for thought. (3)>>space already has the conditions to allow for these chemical reactions to take place beyond Earth. As for viruses, well, as I touched on we don't even quite know how our own Earth viruses fit into the tree of life, if they've descended from living things or evolved alongside them - or indeed whether they're even a single group, or just a catch-all term for a number of entirely different things that behave in similar ways. So the word "virus" is already a less systematic and more functional term, whether they're considered alive or not. I think we can safely use the word "virus" about any being, anywhere in the universe, that's a highly reduced, obligate intracellular parasite consisting of a sequence of genetic information and some helper materials, but no metabolism of its own.(4)>>microbial forms of alien life floating in the upper atmosphere of Venus. In a paper published online today (March 30, 2018) in the journal Astrobiology, an international team of researchers led by planetary scientist Sanjay Limaye of the University of Wisconsin-Madison's Space Science and Engineering Center lays out a case for the atmosphere of Venus as a possible niche for extraterrestrial microbial life."Venus has had plenty of time to evolve life on its own," explains Limaye, noting that some models suggest Venus once had a habitable climate with liquid water on its surface for as long as 2 billion years. "That's much longer than is believed to have occurred on Mars." Supporting the notion that Venus' atmosphere could be a plausible niche for life, a series of space probes to the planet launched between 1962 and 1978 showed that the temperature and pressure conditions in the lower and middle portions of the Venusian atmosphere -- altitudes between 40 and 60 kilometers (25-27 miles) -- would not preclude microbial life. The surface conditions on the planet, however, are known to be inhospitable, with temperatures soaring above 450 degrees Celsius (860 degrees Fahrenheit).(5)>>Mars did once harbor primitive microbial life, with the requisite viruses accompanying it. Hauling back the goods from the Red Planet resonates in some ways as a replay of Michael Crichton's 1969 novel "The Andromeda Strain," which dramatized the idea of alien organisms infecting Earth.In the book, which was made into a film in 1971, alien germs are brought to Earth by a "Project Scoop" satellite. An elite team of secretive first responders, clad in protective hazmat suits, studies and battles the bug within a hush-hush, high-tech underground facility named Wildfire.Will this scenario forever remain science fiction, or could it actually happen in real life? And does the ongoing coronavirus pandemic hold any clues about how to handle samples brought to Earth from Mars, a place that could potentially host extraterrestrial microbes? (6)>>The NEXT place that could have viruses are COMETS . Cambridge astrobiologist Dr. Chandra Wickramasinghe claims that the COVID-19 virus, that's on its peak, may additionally have been resulting from a fragment of a comet that exploded in a brief flash in North-East China in October 2019.The sudden outbreak of a new coronavirus, in Wickramasinghe's perspective, is very probable to have a space connection. He brought the strong localization of the virus inside China is the most brilliant aspect of the disease."[It's probable] that this [comet has embedded an] infective [COVID-19] virus debris that lived in the incandescent meteor," Wickramasinghe said. The scientist took into consideration the seemingly outrageous possibility that masses of trillions of infective viral debris have been then released embedded within the shape of sweet carbonaceous dust.Infectious agents, according to Wickramasinghe, are deemed to be widely wide-spread in the area, which might be carried on comets and may fall toward Earth via the troposphere. "These, we believe, can and have inside the past long gone on to result in human disease epidemics," he said.[ see https://www.panspermia.org/panfluenza.htm ](7)>>Enceladus. The Saturnian moon Enceladus is considered one of the best possible places to look for life in our solar system — and our galaxy — so far. If we were to find life on Enceladus, it would also broaden the types of places we could search for life. Right now, we just look for Earth-like planets close enough to the sun to have liquid water. For many researchers, this tiny, shiny
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| Enceladus. |
cue ball of a moon, just over 300 miles wide, is now the most promising place to look for life elsewhere in the solar system, even more than Mars. The discussion on the possibility of extraterrestrial life in the solar system centers on four bodies: Mars; Enceladus; Europa, a moon of Jupiter; and Titan, another moon of Saturn. (7.1)>>To LOOK AT TITAN . Using data from the NASA/ESA Cassini mission, we have now discovered molecules on Saturn’s largest moon Titan which we think drive the production of complex organic compounds. These are molecules that have never been seen in our solar system before. The discovery not only makes Titan a great contender for hosting some sort of primitive life, it also makes it the ideal place to study how life may have arisen from chemical reactions on our own planet. The molecular building blocks of life are organic compounds including amino acids that can be assembled into proteins, RNA and DNA in living cells. To date, scientists have found these compounds in meteorites, comets and interstellar dust. But the problem is that these materials formed millions of years ago, which means we have no way of knowing how they were created.Excitingly, it seems these compounds are being created on Titan today. Sunlight and energetic particles from Saturn’s magnetosphere drive reactions in the moon’s upper atmosphere, which is dominated by nitrogen, methane and hydrogen. These lead to larger organic compounds which drift downwards to form the moon’s characteristic “haze” and the extensive dunes – eventually reaching the surface. (8)>>If we turn to the possibility of life based on another liquid. Liquid water is an essential requirement for life on Earth because it functions as a solvent. It is capable of dissolving substances and enabling key chemical reactions in animal, plant and microbial cells.Its chemical and physical properties allow it to dissolve more substances than most other liquids. Other characteristics that make it a good habitat for life are its heat conduction, surface tension, high boiling and melting points, and its ability to let light penetrate it. A new type of methane-based, oxygen-free life form that can metabolize and reproduce similar to life on Earth has been modeled by a team of Cornell University researchers.Taking a simultaneously imaginative and rigidly scientific view, chemical engineers and astronomers offer a template for life that could thrive in a harsh, cold world – specifically Titan, the giant moon of Saturn. A planetary body awash with seas not of water, but of liquid methane, Titan could harbor methane-based, oxygen-free cells.Their theorized cell membrane, composed of small organic nitrogen compounds and capable of functioning in liquid methane temperatures of 292 degrees below zero. (9)>>URANUS and NEPTUNE. They are not the same but they have similarities. Both are ice giants composed largely of thick, slushy water, ammonia & methane ices with solid cores about the size of the Earth. Uranus is larger than Neptune. it has a ring system and it is rocked over on it’s side. Neptune while smaller has a higher density and greater mass than Uranus and has the highest wind speeds observed anywhere in the solar system. Since these two planets are often considered twins you might think they are almost exactly alike. There are some interesting similarities. Uranus has a mass about 15 times that of Earth while Neptune’s mass is about 17 times that of Earth. Among the billions of celestial bodies there are bound to be objects that are about the same size. But it is unusual to find two so close together orbiting in the same solar system.To the untrained eye Neptune and Uranus might seem to be just smaller versions of a larger planet like Saturn. But these “twins” are much farther from the sun, which means that many of the chemical compounds on Uranus and Neptune freeze to a much lower temperature than they do on other planets. Both of these planets are composed primarily of oxygen, nitrogen and carbon, much of which is deeply frozen. They are sometimes referred to as Ice Giants. (10)>>THE DWARF PLANET PLUTO . The decision by the International Astronomical Union (IAU) to demote Pluto to dwarf planet status. Our solar system went from having nine major planets to having eight major planets. Pluto, once considered the outermost planet, became more widely known as the largest of a number of small bodies in the outer solar system. Neptune, the eighth large planet out from our sun, is now considered outermost major planet. The IAU formulated a new definition of what it means to be a planet. The IAU’s XXVIth General Assembly formalized the decisionand announced it on August 24, 2006. The public and many astronomers didn’t take it lightly, with some declaring they would still consider Pluto a planet. The word plutoed – meaning to demote or devalue something – entered the global lexicon.Why did it happen? We still get questions about this today. Prior to 2006, astronomers hadn’t gotten around to establishing clear standards – such as a minimum size or mass, or other considerations – by which an object might be categorized as a solar system “planet” versus “dwarf planet.”They began to see a need when many small bodies – such as Haumea and Makemake – began to be discovered in the outer solar system. Eris, also considered a dwarf planet, is even more massive than Pluto! So if Pluto is a planet, why shouldn’t Eris be granted planet status as well? That was the question the IAU asked itself, which led to its formation of a Planet Definition Committee and ultimately the 2006 decision.
