Category: Science

Astronomers declare Asteroid near Jupiter to be an Interstellar Immigrant.

It was only last October that astronomers discovered the first known interstellar visitor to our Solar System. (See my post of  4Nov17) The asteroid, which was discovered by the Panoramic Survey Telescope and Rapid Response System or Pan-STARRS telescope in Hawaii, was moving much too fast for the Sun’s gravity to keep it in a permanent orbit so it must have come from interstellar space and only spent a short period of time going around our Sun.

Astronomers named the asteroid Oumuamua, Hawaiian for scout, and we learned quite a lot about it in the few months Oumuamua was close enough to study. Astronomers found the composition of Oumuamua was like that of an iron-nickel meteorite than a dirty snowball like a comet. They also discovered that Oumuamua possessed a very unusual cigar shape being at least ten times longer than it was wide. The image below is an artist’s impression of Oumuamua.

The Interstellar Visitor Oumuamua (Credit: Space.com)

Now the astronomers at Pan-STARRS have discovered another asteroid that, while it is a permanent member of our Solar System, its orbit is so strange that it may not be an original member. Orbital simulations suggest that it could be an interstellar immigrant.

The new find hasn’t been given a name yet so I’ll be using its astronomical designation, which is 2015 BZ509. Now 2015 BZ509 orbits the Sun with a semi-major axis (Average distance) only slightly less than that of Jupiter. The most unusual thing about its orbit however is that 2015 BZ509 orbits in the opposite direction of nearly every other object in the Solar System. It has what is called retrograde motion. The image below shows a telescopic view of 2015 BZ509, it’s in the yellow circle.

Two pictures of the Asteroid 2015 BZ509, in yellow circle (Credit: Los Angeles Times)

To understand what retrograde means let’s imagine ourselves looking down on the Solar System from the Sun’s north pole (which happens to correspond to Earth’s north pole). Looking at the image below of the inner Solar System ( the whole thing is too big to really illustrate my point), the orbits of the planets, the spin of the Sun and the spins of all of the planets, even the motions of the major moons all go counterclockwise. The reason for this is simple; the original gas and dust cloud that formed our Solar System must have had a counterclockwise spin and so the Sun, the planets and all of the moons shared that counterclockwise motion.

The Inner Solar System (Credit: University of Rochester)

Objects that orbit in a clockwise motion are very rare, but not completely unknown. There is an entire class of objects known as Centaurs who orbit the Sun between the orbits of the gas giant planets (Jupiter, Saturn, Uranus and Neptune). This small number of asteroids are of great interest to astronomers simply because of their unusual orbits and astronomers have done an enormous amount of computer modeling trying to understand how those asteroids got those orbits. What they found was that the powerful gravity of the gas giants could capture an object out of the Ort cloud and an object so captured could on occasion wind up going the wrong way. Astronomers also found that such orbits are unstable, lasting less than 100 million years. The image below shows a few of the crazy orbits of the Centaur asteroids.

Centaur asteroid Orbits (Credit: Nick Fiorenza, Lunar Planner.com)

2015 BZ509 isn’t a Centaur however, it’s not between two gas giants its in an orbit very similar to Jupiter’s only backward. And when researchers F. Namouni of the Universite Cote d’Azur in Nice France and M. H. M. Morais of the Universidade Estadual Paulista in Sao Paulo Brazil carried out one million simulations of the orbit of 2015 BZ509 they found that its orbit was stable going back to the very beginning of our Solar System four and a half billion years ago.

So if 2015 BZ509 has been sitting around Jupiter pretty much since the formation of Jupiter and the other planets how did it get its backwards orbit. Doctors Namouni and Morais theorize that, back when the Solar System was very young and we were a part of a star cluster like the Pleiades or the Orion nebula 2015 BZ509 could have been grabbed from another star system that was also in the process of formation.

Personally I think that claiming that 2015 BZ509 is interstellar in origin just because it has a very unusual, but nevertheless stable orbit is a bit of a stretch. I want to see some more evidence, and I expect I’ll get my wish as astronomers continue to study this fascinating object.

P.S. Orbital dynamics isn’t my forte but I do know how to calculate the difference between the specific energy of an object (that’s the energy per kilogram of mass) between being free of the Sun’s gravity and being captured at Jupiter’s orbit. I calculate that 2015 BZ509 would have to have somehow lost 85 million Joules of energy for every kilogram of its mass if it is an interstellar immigrant. That’s lot so you can see why I’m more than a little doubtful!

 

The Coriolis “Force”, it’s what makes Hurricanes, Tornadoes and the water in your Toilet spin.

Did you ever take a ride on a Merry-Go-Round with a friend and while the ride was spinning you tried to toss something, let’s say a piece of candy to them? Well I bet the candy took off in a sharp turn and you missed by a mile! You’re left with a surprised look on your face as the candy flies off as if it had a mind of its own!

Think about it, because of the motion of the Merry-Go-Round both you and your friend are moving in a circle! That means that by the time the candy gets to where your friend was when you threw it, they’re not there anymore! And because of the circular motion of the Carousel your candy appears to you to take a sharp turn in the opposite direction of the spin of the Merry-Go-Round! Click on the link below to be taken to a youtube video of a very nice demonstration of what I’m describing from a freshman physics course at MIT.

This effect is commonly known as the Coriolis “Force” although any physicist will point out that there’s really no force acting on the candy. Technically what’s happening is that you are in a rotating frame of reference, the Carousel, but once you let go of the candy it no longer is. This makes the candy’s straight line motion look to you as if it’s curved. That’s right the candy is moving in a straight line, you’re on the Merry-Go-Round, you’re the one going in a circle!

Now we all live our lives on a great big Merry-Go-Round, better known as the spinning globe of the Earth, so the coriolis effect has a major influence on many of the phenomena we see every day. (That’s right you flat Earth loonies, the Earth is a spinning globe and the phenomena I’m about to talk about are demonstrations of that fact!!!). Since the Earth’s equator is 40,000 km in circumference and the planet rotates once every 24 hours that means that a person standing on the equator is actually moving at 1666.6 kilometers per hour (40,000km / 24 hours=1666.6 kph). On the other hand someone standing at the north or south pole isn’t moving at all (relative to the center of the Earth at least) but simply turning around once every 24 hours. In between you can calculate your speed if you know your latitude using the formula:

v=1666.6 x sin(Latitude)

For example I live in Philadelphia at a latitude of 40º N so I’m moving at a speed of 1071 kph. The image below illustrates this.

Your speed due to the Earth’s spin depends on your latitude.

This difference in velocities has a major effect on our weather and to see how let’s look at how a LOW pressure system behaves. Now I hope you remember that a low pressure system is also a storm system because it pulls in and condenses moisture laden air leading to rain and strong winds.

Looking at the image below we see that a super strong Low Pressure system is sitting right over me in Philadelphia. This low is so strong it’s pulling in air all the way from the equator and the north pole. Now as I said above Philadelphia is moving at 1071 kph and so is the air above it. The air at the equator is moving much faster however, 1666 kph so when it get pulled toward the low it misses, going in front of the low, to the east. The air at the pole however is moving much slower so it misses the low to the rear, the west. The result is a counter-clockwise flow of air around the low pressure system giving hurricanes and tornados their familiar spiral shape, see image of a hurricane below. That is why you often hear your local meteorologist, in the northern hemisphere, talk about storms having a counterclockwise motion while a fair weather system has a clockwise spin.

Hurricane Irma Spinning Counter-Clockwise (Credit: National Geographic)

The mirror image of this happens in the southern hemisphere. The air from the equator still misses to the front of the low and the air from the pole misses to the rear but because the equator and pole have flipped positions, see image below, the low now has a clockwise flow. The very movements of the weather systems on Earth are due to our planet being a spinning globe.

Before I go I’ll mention one more example of the coriolis effect that you probably see several times a day, whenever you flush your toilet in fact. Think about it, isn’t all that water flowing out causing a low pressure system, and doesn’t the water spin counter-clockwise north of the equator and clockwise south of it. That’s the coriolis effect right inside your own home.

And you don’t have to be very far north or south of the equator to see the spinning. Click on the link below to be taken to a youtube video shot at the equator in Uganda. The presenter demonstrates the coriolis effect just a few feet north of, right on and a few feet south of the equator.

https://www.youtube.com/watch?v=_xqtXBnuXiA

So remember, the next time some you arguing with a flat Earth idiot just flush the toilet and tell them the spinning globe of the Earth is causing the spin in the water. Then you can flush their nonsense down the toilet as well.

 

 

The SuperCDMS Experiment and the Search for Dark Matter.

It was back in my undergraduate days (early 1980s) that the topic of Dark Matter first began to be seriously considered by astro-physicists and cosmologists. The idea that there was some kind of matter in the Universe that was for some reason invisible to our telescopes was considered as a solution to two of the biggest problems in our study of the Universe.

The first problem concerned the stability of all of the rotating spiral galaxies we were studying. The idea that the stars in the outer reaches of a galaxy, like our own sun, would orbit around the center of the galaxy made perfect sense. After all, it was just Newton’s laws of gravity at work we thought. However, when we estimated the mass a galaxy, basically counting the numbers of stars, and measured the speed at which the stars were orbiting we found that there wasn’t enough mass, the galaxies should fly apart! There had to be some mass that we weren’t seeing, some invisible matter whose gravitational attraction was holding galaxies together. See image below.

Spiral Galaxy Rotation (Credit: Giphy)

At the same time other astronomers were studying the Cosmic Microwave Background (CMB), the leftover radiation from the original big bang, and used that data to calculate how the Universe should look today. Problem was that the calculations didn’t match the reality, not based on the amount of mass we could see. In order to make the calculations work the Universe had to have about four times as much invisible matter as the matter we could see.

O’k so the Universe had a lot of matter that didn’t emit light the way normal matter did in the stars, some sort of Dark Matter. The search was on to discover just what this Dark Matter was. The astro-physicists, with some help from the high-energy physicists, came up with a lot of ideas: Cold Dark Matter, Hot Dark Matter, MACHOS (Mass Concentrations) and WIMPs (Weakly Interacting Massive Particles).

That was almost forty years ago now, and we’re still waiting for direct experimental evidence of any kind of dark matter. Oh, we’ve made some progress, everybody pretty much agrees on WIMPs as Dark matter but that doesn’t mean everybody’s right. We need good hard evidence.

Hopefully soon we’ll get some from the Super Cryogenic Dark Matter Search now under construction by the Stanford Linear Accelerator Center (SLAC) at Stanford University and which will be set up over 2000 meters underground at SNOLAB at the Vale Inco Mine in Sudbury, Canada.

Setting up sophisticated, delicate physics experiments deep down in an old mine because all of the rock above the instruments helps insulate them from the interference of cosmic ray particles. And the SuperCDMS needs to eliminate all of the interference it can, it’s trying to measure the tiny amount of energy produced when a WIMP bounces against a normal atom. The image below shows the Sudbury neutrino telescope already in operation at Sudbury.

Neutrino Telescope in Sudbury Mine (Credit: Pinterest)

Physicists calculate that such collisions are very rare, you may have to wait many trillions of trillions of years for a particular atom to experience such a collision. Rather than waiting so long physicists will use trillion of trillions of atoms and then ‘listen’, that’s right listen for the sound of any collisions. Technically the intent is to detect the minute phonon signals of the collisions with germanium crystal detectors. The image below shows one of SuperCDMS’s detectors.

SuperCDMS Detector (Credit: SuperCDMS)

But in order to ‘hear’ the sound of a WIMP hitting an atom the physicists have to eliminate as much as possible the racket caused by all of the atoms hitting each other caused by thermal vibrations and the only way to do that is to reduce the detector’s temperature down to a small fraction of a degree above absolute zero, hence Super Cryogenic Dark Matter Search.

The experimental setup is shown in the image below. The cyrostat and detector section is modular in design allowing more detectors to be installed in the future. Around the detectors is a lining of lead (Pb) shielding with water shielding around that. The entire apparatus is then mounted on seismic isolators because even the slightest outside movement could be picked up as an erroneous signal. It’s often true that in today’s physics experiments, eliminating the unwanted signals can be a bigger job than detecting the minuscule signal you’re looking for!

SuperCDMS Experimental Layout (Credit: SuperCDMS)

SuperCDMS is scheduled to be up and running by the year 2020 but it will take four or five years of data collection before any results can be announced but I’ll let you in on my opinion. Now I’ll be very happy to be proven wrong but I’ve always been skeptical of WIMPs, we’ve been looking for them for forty years and have no evidence so far. Personally I was a MACHO supporter, basically the idea here was that for every star we can see there would be dozens of smaller brown dwarfs, objects just too small to start nuclear fusion and so don’t glow, and on top of that there would be literally thousands of planetary sized objects in interstellar space. I still think we need to consider MACHOS as a possible solution to the Dark Matter problem.

Fossil Reveals First Steps in the Evolution of the Beaks of Birds.

In today’s world the taxonomic group we call birds have two unique anatomic characteristics that no other animals possess, feathers and beaks. Trying to understand how these distinct features evolved has been a goal of paleontologists since Darwin’s days.

Considerable progress has been made in the study of feathers with the discovery not only of early birds with feathers like Archaeopteryx but also of new evidence that some species of dinosaurs sported primitive feathers for insulation. The images below show archaeopteryx and a feathered T-rex (yes some paleontologists think the mighty T-rex might have been partially covered by feathers).

Archaeopteryx: Feathers and Teeth! (Credit: Independent)
T-rex with Feathers? (Credit: American Museum of Natural History)

Evidence for the evolution of the bird’s beak however is much sparser; and the development of the beak is mostly unknown. Beaks by the way are composed of bony upper and lower mandibles (jaws) that are covered by a thin later of keratin (the protein in your hair and fingernails) and which lack teeth composed of dentine. Although similar in some ways to the mouths of other vertebrates the avian beak is a structure unique to birds.

The big problem in studying the development of the beak is that usually the delicate bones making up the skull of an early bird are so squashed that little can be learned from them. One thing we were certain of however was that feathers came first; there are many fossil specimens, again like Archaeopteryx, of early birds covered with feathers but sporting a mouthful of teeth.

Now a new study, combining both recent fossil finds and a reexamination of older specimens with the latest instruments, is changing that. It started in 2014 when Kristopher Super, then an undergraduate student at Fort Hays State University in Kansas, found an almost complete fossil of the well know early bird Ichthyornis dispar encased in limestone. A transitional species between the dinosaurs and birds I. dispar was a seagull sized creature that lived between 66 and 100 million years ago.

When the find was shown to Yale Professor of Paleontology Bhart-Anjan Bhullar he suggested that instead of trying to remove the specimen from the limestone it should be scanned by computerized tomography (CT scanning). What they found led them to perform CT scans on three other fossils for conformation. There, right at the very end of a long bony jaw filled with very sharp teeth sat a tip covered in keratin, a beak. Professor Bhullar suggests that even a tiny tip of a beak may have given I. dispar a greater ability to manipulate its food and preen its feathers. Exactly the behavioral activities that modern birds use their beaks for. The image below shows a composite of the CT scans of I. dispar.

Ichthyornis CT Scan (Keratin Beak is at tip) (Credit: Science Magazine)

The scientists also found that the skull of I. dispar shared a mixture of dinosaur and bird like features, a large brain case like that of a bird along with the powerful jaw muscles of a velociraptor like dinosaur. The evidence provided by I. dispar pushes back by millions of years the development of the bird’s beak while at the same time indicating that birds may have existed for millions of years with both a partial beak and a mouthful of teeth. The image below shows an artists rendering of the head of Ichthyornis dispar.

Ichthyornis Head (Artist’s Rendering) (Credit: Science Magazine)

The first fossils of Ichthyornis were discovered in the 1870s by the US paleontologist Othniel C. Marsh, famous for his ‘Dinosaur Wars’ with Edward D. Cope. Even after almost 150 years we’re still leaning more about these amazing dino-birds.

Space News for May2018.

Several stories of interest have been happening in space exploration over the past month so let’s get to it!

Once again Space X is rewriting the rules on how to get into orbit cheaply and efficiently. Elon Musk’s Falcon 9 rocket has now been successfully launched more than fifty times with Space X recovering more than twenty of the first stages. For the last two years the Falcon 9 has flown more often than any other rocket making Space X the leader in the drive to commercialize space travel.

The latest Falcon 9 rockets have been considerably improved and updated from the first vehicle that was launched in 2010. Lighter, more powerful engines combined with larger fuel tanks have nearly doubled the Falcon 9’s payload to orbit.

Now Space X is rolling out a new version of the Falcon 9, referred to as Block 5 by Space X. The Block 5  version has been optimized for recovery and reuse. The intention is to reuse the Falcon 9 first stages at least ten times each in order to maximize the cost savings. The first launch of the new, improved Falcon 9 is scheduled for next week but since this is a new design there may be delays as Space X wants to be certain that everything is a go for launch. The image below shows the new, optimized Falcon 9 Block 5.

Falcon 9 Block 5 Rollout (Credit: Space X)

Perhaps the success of Space X is making their competitors a little nervous because just this past week Boeing saw fit to publicly remind everyone that their Space Launch System (SLS), which hasn’t flown yet, is bigger than Space X’s Falcon heavy, which has. I think that ‘my rocket is gonna be bigger than your rocket’ doesn’t quite match the success Space X has had recently. The image below shows what the SLS will look like when it is finally tested, hopefully next year.

Illustration of the Space Launch System (Credit: NASA)

My second story is actually an update of a story I blogged about back on 27Jan2018. In that post I described the small nuclear power plant that was developed by NASA’s Glenn Research Center in Cleveland Ohio. Called the Kilopower Reactor Using Stirling Technology (KRUSTY) the prototype has been undergoing testing to the Department of Energy’s Nevada National Security Site. The image below shows the prototype KRUSTY.

NASA’s kilowatt Nuclear Reactor KRUSTY (Credit: Youtube)

The first two tests to be carried out were simple environment checkouts without the reactor being powered up in any way. During the third test the reactor’s core was slowly powered up in order to heat the core. The final test consisted of a full power test of 28-hour duration intended to simulate an actual mission.

The prototype KRUSTY reactor is designed to output one kilowatt of electrical power but the concept is intended to be scalable up to ten kilowatts. NASA scientists are of the opinion that four such ten-kilowatt units would be sufficient to power a manned outpost on either the Moon or Mars. The image below shows what a KRUSTY unit could look like deployed on the Moon.

KRUSTY on the Moon (Credit: Popular Mechanics)

Over the last forty years NASA has initiated several programs for the design and testing of a small nuclear reactor for use in outer space. However all of those programs were canceled before testing had even begun primarily because of public aversion to nuclear power. Hopefully the day will soon come where KRUSTY is providing the electrical needs of NASA astronauts on another world.

 

My final story concerns a brand new NASA program for an initial design of the space telescope of the future. What scientists at Cornell are proposing is a modular concept of a telescope that will build itself piece by piece in orbit until it is about thirty meters across. The image below shows both a single module and a partially assembled telescope.

Modular Active Self Assembling Space Telescope design concept (Credit: NASA, Cornell University)

Professor of mechanical engineering Dmitry Savransky leads a team of fifteen scientists and engineers who have been awarded a Phase I NASA Innovative Advanced Concept grant of $125,000 for an initial feasibility study.

The basic idea is for the Telescope to be constructed from one thousand or more identical pieces that can be placed into orbit one at a time. Since the larger a telescope is the more light it can gather to study we want to put the largest possible into orbit but also the larger a telescope is the more difficult it is to get into space.

This certainly makes the idea of putting the telescope into orbit in pieces and assembling them there is a logical way to go. However the final configuration of the optics of any telescope has to be so precise that the concept of a prefabricated space telescope may simply be unworkable. Only time and study will tell if a modular space telescope is the way to go or not. This is a Phase I study after all.

 

 

TESS: NASA’s new Exoplanet Hunting Satellite.

NASA’s Transiting Exoplanet Survey Satellite (TESS) was launched on the 18th of April from the Kennedy Space Center aboard a Space X falcon 9 rocket. Another space success for Space X, which not only delivered TESS to its proper orbit but once again recovered the Falcon 9’s first stage so that can be reused for further missions. The image below shows TESS riding into space aboard a Falcon 9.

Launch of TESS Space Telescope (Credit: Deutsch Welle)

TESS is a replacement for, and an improvement upon NASA’s highly successful Kepler exoplanet hunting space telescope. Kepler’s mission began in 2009 with the spacecraft continuously observing the light output from approximately 150,000 main sequence stars looking for tiny yet periodic dips in the stars light output. Such dips could be caused by one or more planets passing, technically transiting across the face of the star. The image below shows the Kepler Space Telescope and the area of the sky it observes.

Kepler Space Telescope (Credit: NASA)

As of April 2018 the Kepler Space Telescope had identified 2,650 exoplanets that have been confirmed by closer study with ground-based telescopes. Of the confirmed exoplanets 550 are believed to be rocky Earth type planets with nine of those planets orbiting within their star’s habitable zone.

The years have taken their toll on Kepler however. System failures have greatly reduced the telescopes ability to perform and it will run out of the fuel it needs to keep itself in position within a few months. At the same time a new space telescope, with improved performance that could survey a greater number of stars would lead to even more discoveries of exoplanets. Enter TESS, NASA’s new exoplanet hunting space telescope. The image below shows TESS.

TESS Space Telescope (Credit: Many Worlds)

TESS’s mission is different from Kepler’s in several ways however. For one, whereas Kepler stared continually at a very small patch of the sky, about 0.2% of the entire sky, TESS will be able to observe as much as 85% of the celestial globe. On the other hand, while Kepler studied stars as far away as a thousand light years or a little more, TESS is going to concentrate on the stars closest to our own.

The idea here is for TESS to find a large number of exoplanets that are also close enough to us that we can use other telescopes to not only confirm their existence but to actually learn more about them. In particular it is hoped that the soon to be launched James Webb Space Telescope will even be able to discover something about the chemical composition of the atmosphere of some of the planets that are found by TESS.

TESS will be doing other research as well. The satellite’s instruments will also be able to obtain observations of unexpected, transient events such as the optical components of gamma ray bursts. It is also hoped that the observations made by TESS will advance the study of astroseismology, that is the study of the interior of stars through measuring their surface vibrations.

The projected mission time line for TESS is estimated at 15 years but of course that will depend on the fuel usage. If you’d like to learn more about the TESS Space Telescope and its mission the link below will take you to NASA’s official website for the spacecraft.

https://www.nasa.gov/tess-transiting-exoplanet-survey-satellite

Before I go I’d like to quickly mention another piece of NASA news, the cancellation of the planned Lunar Resource Prospector rover. This mission was intended to land a rover vehicle on the Moon to excavate and study materials on the Lunar surface. The primary material of interest was water ice, which has been observed by orbiting spacecraft in the Moon’s polar regions and which it is hoped could to used to provide fresh water and perhaps even rocket fuel in the near future for any long term settlements on our satellite.

NASA’s decision to cancel the Lunar Prospector makes little sense therefore when you consider President Trump’s recent directive for the Space Agency to return manned missions to the Moon before going on to Mars. The knowledge that the rover could have gained could have been very useful to future lunar explorers. Once again we have a situation where the space agency doesn’t seem to have a firm understanding of exactly what it’s long term goals are, let alone how to achieve them. The image below shows a prototype of the Lunar Prospector rover undergoing test.

Lunar Resource Prospector Prototype (Credit: NASA)

NASA Scientists Speculate on Pre-Human Intelligent Life on Earth.

“Nor is it to be thought, that man is either oldest or the last of Earth’s masters.” That is a quote from the story ‘The Dunwich Horror” by H.P. Lovecraft. Several of Lovecraft’s stories deal with the idea that millions of years ago, during the time of the dinosaurs or even earlier, there were intelligent creatures living here on Earth the remains of whose existence the passage of time has practically erased. The image below shows Lovecraft’s ‘The great race of Yith’ who lived in the area we call Australia during the Jurassic period, at least in the story ‘The Shadow out of Time’ that is.

The Great Race of Yith (Credit: Astounding)

Could that be true? Human history only goes back some 6 thousand years but the Earth is over 4 billion years old. If a pre-human species had built a civilization 100 million years ago how would we know? Would there be any traces remaining that we could find as evidence?

Two scientists, Gavin Schmidt of NASA’s Goddard Institute for Space Studies and Adam Frank of the Department of Physics and Astronomy at Rochester University are trying to answer those questions. Together they’ve written a paper ‘The Silurian Hypothesis: Would it be possible to detect an industrial civilization in the geologic record.’ The Silurians by the way are from another science fiction franchise. Back in the 1970s the British TV series Doctor Who ran a series of episodes where the Doctor encounters an ancient race of intelligent lizards who have been in hibernation since the days of the dinosaurs but are now waking up! The image below shows one of the silurians from Doctor Who.

Silurians in Doctor Who (Credit: Doctor Who, BBC)

O’k so the whole idea is inspired by science fiction but so what, so have airplanes and submarines. Science fiction has predicted many things that turned out to be true so lets take a good look at the Silurian Hypothesis by considering how a future intelligent species might discover evidence of our existence!

Now at first you might think that the biggest things humanity has built would survive the best. The pyramids have lasted now for 4 thousand years and they are still in reasonably good shape. But how recognizable will they be in 4 million years, that’s a thousand times their present age. That’s lot of erosion and remember what’s left will just be a pile of limestone, no different than the bedrock its sitting on!

Great Pyramid of Kheops (Credit: Wikipedia)

O’k then what about something like the Golden Gate Bridge. Iron is stronger than limestone and you could never mistake a something like a bridge for a natural formation. That’s true, iron doesn’t erode, it rusts, faster than stone erodes and then it falls to pieces that can be dispersed by wind or water and just become a stray outcrop of iron ore.

Golden Gate Bridge (Credit: Bay City Guide)

Then let’s think bigger, how about entire cities like New York or Mumbai, in fact with sea level rise due to global warming both of those cities may soon be submerged into river deltas that would bury them in new rock formations. Couldn’t the fossil remains of New York City be found 10 million years from now?

Yes, it could, but you have to remember that New York City, indeed our entire industrialized society is only a little over 300 years old and that’s a very, very thin layer in the geologic record (the latest estimate for sediment deposition in the oceans is 1cm of thickness per 1000 years). Worse, our entire urban landscape today is only about 1% of the Earth’s total surface area making the odds of future, non-human geologists finding extensive evidence of our existence very low.

So do Schmidt and Frank think that there are any markers of our existence will survive for millions of years. Yes, but they’re not exactly flattering. For example, one is plastic. All of those bottles, cups and containers we just throw away are forming an unmistakable layer of artificial polyethylene and polypropylene covering much of the globe, making it both easier to spot and identify as a product of industrial civilization. The image below shows the plastic trash island in the Pacific Ocean, a huge amount artificial material that is now larger than any city.

Great Pacific Trash Heap (Credit: Sputnik International)

Other indicators that Schmidt and Frank consider are subtler. The carbon deposited by our burning of fossil fuels will have an unnatural ratio of the isotopes C13 to C12 and similar unnatural ratios will occur to the elements strontium (Sr87 to Sr86) and osmium (Os187 to Os188). It is humbling indeed to think that for all of our importance, as we believe, if we were to destroy ourselves today (Nuclear War or Global Warming or etc) a few million years from now there would be little if anything remaining to prove that we had ever existed!

So perhaps we are not the first intelligent creatures to live on Earth, perhaps one day we will find the evidence to prove this. H. P. Lovecraft and Doctor Who have open minds, maybe we should as well!

Paleontology News for April 2018.

There have been several interesting new discoveries about ancient life over the past month and I think I’ll start in a place that doesn’t usually spring to mind when you talk about paleontology. Scotland.

Now trace fossils, or ichnofossils as they’re technically known, are not the actual remains of ancient animals but rather the remains of their activity. Trace fossils can be anything from a burrow to fossilized feces, called a coprolite. The image below shows the track made by a trilobite as it crawled along the seafloor.

Trilobite Track (Credit: Trilobite.info)

The best known type of trace fossils are of course Dinosaur Footprints! Well a recent discovery on the Isle of Skye in the Scottish Hebrides by paleontologists from the University of Edinburgh has brought to light more than fifty footprints from at least two different kinds of dinosaurs. The collection includes footprints from both a long necked, plant eating sauropod along with the two-legged meat-eating theropods. The image below shows one of the footprints for each of the sauropod and theropod.

Sauropod Footprint (Credit: New Your Times)
Theropod Footprint (Credit: The Guardian)

Back in the Jurassic period when the trace fossils were made the western islands of Scotland were a series of warm, shallow, soggy lagoons, a perfect place to leave footprints. By studying the footprints biologists can learn a great deal about the size, weight and even the gait of the animal that made them. The researchers estimate that the sauropod dinosaur measured two meters tall at its hip and was perhaps ten meters in length counting both its long neck and tail. They also believe that an early ancestor of the famous T-rex could have made the theropod tracks. The paleontologists hope to find more footprints on the Island and have even asked the local residents to keep a look out for them.

And speaking of carnivorous dinosaurs a new species has been identified from the Patagonia region of Argentina. Although the bones of Tratayenia rosalesi were unearthed a decade ago it is just recently that its discoverers, Doctors Domenica dos Santos and Ruben Juarez Valieri of the Museo de Ciencias Naturales in Argentina have identified it as a new species of a type of predatory dinosaur know as a Megaraptoridae.

Specimens of megaraptoridae have only been found so far in South America and Australia and they lived from the middle to late Cretaceous period. While Tratayenia rosalesi superficially resembles the famous T-rex (See image below) the skulls of megaraptoridae are longer and narrower and most importantly their arms are larger and much more powerful. (Remember how T-rex’s arms are such tiny, useless things.) I fact the megaraptoridae are probably more closely related to the velociraptor of the US southwest.

Tratayenia rosalesi (Credit: Andrew McAfee, Carnegie Museum of Natural History)

Only a few specimens of the megaraptoridae have been discovered so far and the researchers who found Tratayenia rosalesi hope it will tell us more about this interesting type of dinosaur.

My final story today doesn’t concern dinosaurs but rather is about their just as interesting contemporaries the Ichthyosaurs. The name ichthyosaur literally means ‘fish-lizard’ and indeed during the Triassic period a group of lizards returned to the sea and evolved into reptile versions of our modern porpoises and whales. Thousands of fossils of ichthyosaurs have been found and many different species have been described.

Now, the discovery of a bone from the lower jaw of a giant ichthyosaur from Gloucestershire in the UK has led a group of paleontologists to reevaluate other fossils from the same area that had been previously identified as ‘dinosaur vertebra’ but which may be other bones from a new species that could be the largest ichthyosaur yet discovered. The images below shows a typical, porpoise size ichthyosaur (by the way we do know that ichthyosaurs gave birth to live babies!) along with a complete fossil of one.

Artists representation of an Ichthyosaur (Credit: Gizmodo)
Ichthyosaur Fossil (Credit: The Fossil Forum)

The researchers, led by Dean R. Lomax of the University of Manchester, estimate that the animal to whom the fossil bones belonged might have been as long as 26 meters. If that estimate turns out to be accurate the ichthyosaur would have been approximately the same size as a blue whale, the largest animal alive today.

 

Space News for April 2018.

There have been several news items over the past month dealing with space exploration so let’s right get to it. I’ll start with the new kid on the block Rocket Lab.

I first mentioned Rocket Lab in my post of 10Feb18 when I discussed the second successful test launch of their Electron rocket. With two successes under their belt Rocket Lab is already planning their first actual paying launch placing two small satellites into orbit that are owned by Spire Global and GeoOptics. The mission is scheduled to take off on April 19th.

Now the Electron is a small rocket, see image below, with a total payload to orbit of only 150-250kg but Rocket Lab is aiming to grab a share of the growing market in miniaturized satellites. Presently small satellites may have to wait months or even years in order to ride up piggyback with some big satellite on an Atlas or Falcon rocket. Rocket Lab plans on using a quick turnaround launch schedule as a part of the company’s sales pitch to bring in business.

Rocket Lab’s Second Successful Launch of their Electron Rocket (Credit: Rocket Lab)

Rocket Lab launches their Electron rocket from their own launch pads in New Zealand into polar orbits at a cost of only about $5 million USD. If this third launch is successful Rocket Lab’s fourth mission, carrying 10 miniature satellites for NASA, could come in the next few months.

Also in my February post I mentioned that the Russian space agency was making plans to attach a new module to the International Space Station (ISS) as a luxury hotel in space. Well the idea of a space hotel is picking up steam as a company called Orion Span has announced plans for its own space hotel hopefully as early as late 2021.

The station/orbiting hotel concept is called Aurora and the planned cost of a twelve-day stay is ‘only’ $9.5 million USD. The initial Aurora will accommodate four paying guests along with two astronaut crewmembers in a pressurized chamber of 160 cubic meters volume. The images below show what the Aurora will look like inside and outside.

Proposed Aurora Space Hotel (Credit: Sia Magazine)
Aurora Outside (Credit: Space.com)

Just how customers will get to the Aurora hasn’t been finalized yet but Orion Span will soon have a choice of companies capable of providing the ride. Space X, Boeing and Blue Origin are all planning to launch a crewed space capsule either this year or next and the possibility of using these commercial, manned space vehicles to maintain a space hotel has often been discussed.

In time Orion Span intends to add additional units to Aurora and one day hopes to even sell permanent space on Aurora as a kind of orbiting condo. The image below shows what Aurora could one day look like.

Aurora Final Configuration (Credit: You Tube)

If you’d like to learn more about Orion Span’s plans for their Aurora space hotel click on the link below to be taken to their site.

https://www.orionspan.com/

Speaking of Boeing’s Starliner manned space capsule; the first, unmanned launch is now only months away with the second manned mission is less than a year. And now there’s a possibility that NASA might want Boeing to add a third astronaut to the second mission and turn the second test flight into a full mission to the ISS.

You see NASA has only scheduled to fly astronauts to the ISS on Russia’s Soyuz spacecraft through the end of next year so the space agency has to get its commercial space program up and running before then. The timing is tight, especially because both Boeing and Space X have seen several delays in their original schedule. The deal isn’t done yet; NASA still has to perform a technical evaluation of switching from a test flight with a visit to the ISS to a full six month mission. The image below is an artist’s representation of the Boeing Starliner docking at the ISS, something we’ll hopefully see for real in less than a year.

Boeing Starliner docking at the ISS (Credit: Youtube)

Finally before I go, did you see it? Did you see China’s Tiangong-1 space station as it fell back to Earth? Well either did anyone else. After all of the hysteria by the chicken littles out there the Tiangong-1 ended up falling harmlessly into the middle of the Pacific Ocean and apparently nobody even got to see anything. In fact in all of the history of space exploration on one has even been harmed by debris falling from space and very few people have ever even seen anything fall from space! Only goes to show just how big our planet really is!

 

 

 

 

The CUORE Experiment in Italy releases its first Results. The Search for New Physics.

Perhaps the most sophisticated, sensitive experiment even attempted is the Cryogenic Underground Observatory for Rare Events or CUORE now underway at Laboratori Nazionali del San Grasso in Italy. To order to give you an idea of just what lengths the scientists have gone to in order to achieve such sensitivity the researchers boast of having build “the coldest cubic meter of space in the known Universe!”

And they’re going to need it; the CUORE team are looking for subatomic events so rare that they happen once or twice a year in 100 kilograms worth of atoms. The specific reaction that the CUORE team is studying is the extremely rare double beta decay, they’re trying to see whether or not two neutrinos are produced, as the Standard Model of Elementary Particles requires.

Let me take a step back and describe single beta decay first. Back in the early 20th century physicists found three distinct types of radiation, alpha, beta and gamma rays. Beta radiation was found to occur when a neutron broke up into a proton and an electron, the electron is the high energy beta particle. Problem was that some of the energy of the neutron went missing, an apparent violation of the law of conservation of energy. It was the physicist Wolfgang Pauli who suggested in 1935 that there was another particle as well, a neutral particle with little or no mass that would be very difficult to detect. The image below shows a Feynman diagram of the beta decay process (The W particle in the middle is the boson that carries the weak nuclear interaction). Detecting neutrinos turned out to be so difficult that in fact it took experimentalists 25 years to finally prove that the neutrino was real.

Feynman Diagram of single Beta decay

Single neutrino decay happens quite often, in fact a free neutron, one not in a nucleus will undergo beta decay with a half life of about 12 minutes. (See my post of 4Mar2017). Double beta decay, where two neutrons simultaneously decay to two protons and two electrons, is far rarer and was only proven to exist in 1987.

Now it’s been suggested that double beta decay might not produce any neutrinos! This would require the neutrino to be its own anti-particle so that they would annihilate each other. Such a reaction would be a violation of conservation of lepton number, a key element of the Standard Model of elementary particles. So physicists are very interested in the possibility of neutrinoless double beta decay. The image below shows the Feynman diagrams for double beta decay with and without neutrinos.

Double Beta decay, left with neutrinos, right neutrinoless

There are several reasons why physicists are so interested in neutrinoless double beta decay. One is that it would indicate a possible channel to explain why there is more matter in our Universe than anti-matter while at the same time it could also enable us to measure the tiny rest mass of the neutrino.

Now as I said double beta decay is very rare. You need to observe all of the atoms in kilograms of a material that is capable of double beta decay in order to see one or two a year! And then you have to measure the total energy of both of the electrons to make certain that they got it all, with no neutrinos the electrons get all of the kinetic energy generated.

The experiment the CUORE team has developed uses a device known as a bolometer that will actually measure the heat generated by a single subatomic event. There are 988 total bolometers composed of crystals made from the chemical TeO2 where Te is the element whose isotope Te130 is capable of double beta decay. It is in order to measure the tiny amount of energy released by the double beta decay that all 988 bolometers have to be maintained at the unbelievably cold temperature of 10mK (That’s 10 thousandths of a degree above absolute zero Kelvin), the coldest place in the known Universe. The image below shows the detector ‘towers’ ready to be installed in the cold chamber.

CUORE Detectors before installation (Credit: Meteoweb.eu)

Before I forget I need to mention that in order to prevent radiation from outside, primarily cosmic rays, interfering with the measurements the detectors are first wrapped in lead shielding and then the entire experiment is buried deep underground.

The CUORE collaboration, which consists of over 150 scientists from around the world, have just released the results of the first year of the experiment and so far it looks like the standard model still stands. The CUORE team puts the half-life of a neutrinoless double beta decay at greater than 1.5 x 10^25 years. That doesn’t mean that neutrinoless double beta decay never happens, you can never prove something never happens, it means on average you’ll have to wait 15,000,000,000,000,000,000,000,000 years to see a nucleus of Te130 produce a neutrinoless double beta decay.

The CUORE experiment will continue to gather data, looking not only for neutrinoless double beta decay but also for possible signs of minute interactions between the material in the detectors and hypothetical Dark Matter particles called ‘WIMPS’, Weakly Interacting Massive Particles.

Another thing I like about CUORE however is that it is a search for new physics at low energy; it is an experiment that doesn’t need the huge particle accelerators like those at CERN or Fermilab. I hope CUORE does find new physics of some kind and I’ll let you know when it does.