Sunday, July 9, 2017
Busy Aliens?--An Examination of Przybylski's Star
Curiosity can be a dangerous thing leading to the discovery of all sorts of facts that either challenge existing beliefs, or for some open the door to knowledge showing the spectacular and bizarre nature of the universe. Since the European Renaissance, scientific inquiry has done just that, we've gone from believing our world is the center to the universe to understanding that our planet circles an average yellow-star which is on the outskirts of a boring spiral galaxy lost among trillions of others.
The last real item separating us from the rest of the cosmos is that we have no idea if both intelligence life and simpler organisms exist anywhere else. The probes we've sent out into the solar system strongly suggest the presence of liquid water underneath the surface of several moons of Jupiter and Saturn allowing for the possibility of things like bacteria and other single cell organisms. Many scientists hold out the hope that similar conditions might exist underneath the surface of Mars, sort of like underground reservoirs of liquid water protected from the near vacuum of the surface and the unfiltered UV light coming from the sun. Long story short, while no respectable scientist will go out and say he or she is certain we share the solar system with simple organisms, but they would love to have a more robust space program that would determine that fact. From what I've read and seen on videos, unless humans get real stupid and wreck the planet or commit mass suicide we should know whether or not other life exists in our solar system within fifty years.
It is the search for intelligence life where we have little chance of answering that question barring the interception of radio signals from interstellar or intergalactic space. Yes, there is a more than zero chance that an alien starship might just happen to see our little planet and decide to stop by and say hello. But that “more than zero chance” is so infinitely small it would be better for the average person to plan on winning the lotto than expecting such an event from ever happening. Astrophysicists and other astronomers have made some curious observations about other stars in the galaxy that right now they can't readily explain with existing theories causing a few to hesitatingly suggest the presence of advanced alien civilizations.
The first example is KIC 8462852, which stirred up the media when it was found something was causing that star to periodically dim up to twenty-five percent suggesting something really big was orbiting it. Ideas of why it was dimming an unusual amount ranged from an asteroid field, a cluster of comets, to debris leftover from the collision of two planets. None of them really satisfied the observations leaving someone to jokingly suggest some really industrious aliens were building a Dyson sphere around the star to collect all that easy solar energy.
With curiosity running at warp speeds, the Search for Extraterrestrial Intelligence (SETI) guys and gals began scanning the star looking for radio communications between all those busy aliens working to enclose the star. None were detected, but fuel was further added to the possible alien fire when astronomers looked at the data collected over the last hundred years or so of observing that star suggesting the dimming has has grown over that time. The actual nature of this dimming is still unknown leaving KIC 8462852 to be the subject of continued intense investigation, although recent ideas put forward squarely put the cause back into the non-alien induced reasons.
Then there is Przybylski's Star, located roughly 370 light-years away, is showing seriously bizarre characteristics that suggest the presence of elements unknown to Earth or maybe aliens dumping heavy substances into it as a way to reveal their existence.
In 1961, the Polish-Australian astronomer Antoni Przybylski discovered that this star had a peculiar spectrum that would not fit into the standard framework for stellar classification. Przybylski's observations indicated unusually low amounts of iron and nickel in the star's spectrum, but higher amounts of unusual elements like strontium, holmium, niobium, scandium, yttrium, caesium, neodymium, praseodymium, thorium, ytterbium, and uranium.
Przybylski's Star also contains many different short-lived actinide elements with actinium, protactinium,neptunium, plutonium, americium, curium, berkelium, californium, and einsteinium being detected. Other radioactive elements discovered in this star include technetium and promethium.
In normal-sized stars like our sun, as it ages and runs low on hydrogen it gets hotter until it starts fusing its remaining fuel into iron. While the sun is even now slowly getting hotter when it fuses iron that when it goes seriously old age and does the expansion out beyond the orbit of our planet. No real worries though, without humans screwing things up, we've got about a billion years before the increasing temperature makes Earth too hot for liquid water and about another three billion before it gets incinerated.
When larger stars run out of fuel they go super nova, the temperatures and pressure involved in those explosions forge all the heavier elements like silver, gold, and many of the heavy elements being detected in Przybylski's Star. So, long story short with Przybylski being one classification bigger than our sun, and because it clearly hasn't exploded, why it contains those types of elements is quite bizarre.
The going non-alien explanation is that there is some source, like a nearby neutron star, feeding the elements into hot plasma that makes up the star. Another, almost as wild possibility as aliens, is that Przybylski's Star somehow contains a as yet unknown on Earth heavy element that is simply decaying into the ones listed above. Once again, how this unknown element was created without any nearby super nova remnants is a big mystery.
Just because when you eliminate all the other possibilities whatever is left, no matter how improbable, must be considered. The one explanation half jokingly suggested is that aliens are producing mass quantities of heavy elements and then feeding them into Przybylski's Star in an attempt to get noticed by other intelligent species. A seriously fascinating idea but although, like Carl Sagan once said, extraordinary claims must come with extraordinary evidence. This method does seem crazy, but who can tell what another species with technology far more advanced than our own might consider a good idea.
Realistically, there is probably a far more reasonable explanation as to why Przybylski's Star has those wacky elements circulating in its plasma. For a short time scientists entertained the idea that pulsars, rapidly rotating neutron stars, might be navigational beacons for aliens cruising around in their starships. But for me Przybylski's Star and the curious nature of KIC 8462852 are enough to keep hope alive that the SETI guys and gals might just have an exciting announcement to share with the world one day.