Science – Page 49 – Scienceandsf -A Blog Published by Robert A. Lawler

Charles Messier’s Catalog, What it is and How it gives us a Quick Survey of What Sort of Objects make up this Universe of Ours. Part 2 of 2.

(Note: This blog post is the second of two posts because the subject of the objects in Messier’s catalog turned out to require a wide ranging and lengthy discussion. This is Part 2; Part 1 was published on 21 July 2018.)

In my last post I mentioned how a good night of star gazing had inspired me to write about the French astronomer Charles Messier and his catalog of 110 fuzzy objects that you can see in the night sky with binoculars or a small telescope. I mentioned how these fuzzy objects, and others like them, are now the subjects of intense study by astronomers.

I mentioned further how the Messier objects can be broadly divided into six types before I began discussing at some length three of those types, Open Star Clusters, Globular Star Clusters and Gaseous Nebula. In this post I will complete my survey by describing the remaining three types, Planetary Nebula, Supernova Remnants and finally Galaxies.

Planetary Nebula (M57 the Ring Nebula): The best known planetary nebula is the famous Ring Nebula, M57 in the constellation of Lyra. See image below. To find the Ring Nebula first find the brilliant star Vega, the third brightest star visible in the northern hemisphere and the brightest star in Lyra. The second brightest star in Lyra (β Lyra) is about a fist’s distance to the south of Vega and the Ring Nebula is near β Lyra. Be warned however, the ring nebula can be quite difficult to spot, which of course is another way of saying I often have difficulty finding it.

Ring Nebula, M57 as Photographed by the Hubble Space Telescope (Credit: NASA)

Planetary nebulas are so named because about two hundred years ago the French Mathematician Pierre-Simon Laplace hypothesized that planetary systems, like our own Solar System, formed from a disk of material around a new star. (See my blog Post of 5July2018)

Several of the objects in Charles Messier’s catalog seemed to resemble the disks of material Laplace talked about and so they were christened ‘Planetary Nebula’. Unfortunately we now know that planetary nebula are actually dying stars, stars who have used up all of their initial hydrogen fuel and who have begun burning helium. At this stage in a star’s life it puffs up to many times its previous size and begins expelling much of its outer material. It is this expelled material that forms the disk observed as the planetary nebula.

About five or six billion years from now our own Sun will become an object very much like the Ring Nebula. It will, over the course of several hundred million years expel about half of its mass back into interstellar space leaving behind only an intensely hot but nevertheless dead core known as a white dwarf star.

Supernova Remnants (M1 The Crab Nebula): To find the Crab Nebula you need to find the horns of Taurus the bull. The Crab Nebula sits between the points of the two horns, closer to and below the horn on the left. Again the Crab Nebula is not easy to spot but you can find many images of it on the web, such as the one below.

Crab Nebula as Photographed by the Hubble Space Telescope (Credit: NASA)

Not all stars die as slowly and quietly as did the star that formed the Ring Nebula. Large, heavy stars that are more than five times the mass of our own Sun are fated to end their lives as Supernovas, massive explosions that can briefly increase a star’s brilliance hundreds of billions of times. The material flung outward by the force of the supernova will become a type of nebula known as a supernova remnant.

The famous Crab Nebula in the constellation of Taurus is one of these. The supernova that gave birth to the Crab Nebula was actually observed and recorded by Chinese astronomers way back in the year 1054 C.E. Today we know that what remains of the actual star that went nova is an incredibly dense neutron star, spinning on its axis thousands of time a second spewing out radio waves in pulses making it an object known as a Pulsar. If you’d like to hear the actual radio emissions from the pulsar at the heart of the Crab nebula click on the link below to be taken to Jodrell Bank Radio Observatory’s web page of pulsar transmissions. (The Crab Nebula is the sixth one down but Pulsar Number 1 is actually a better one to listen to!)

http://www.jb.man.ac.uk/pulsar/Education/Sounds/

Galaxies (M31: The Andromeda Galaxy): So far all of the objects in Messier’s catalog that I’ve described have been members of our own galactic neighborhood. The final type of Messier objects are other galaxies of which the most famous is the Andromeda Galaxy. Andromeda is a naked eye visible object; indeed at some two million light years distance it is the farthest object that can be seen with the naked eye. The image below shows what Andromeda looks like through a powerful telescope.

To see the Galaxy without binoculars or a telescope however you’re going to have to find REALLY dark skies because it is just a very faint smudge of light. The Galaxy itself is just off of the knee of the constellation Andromeda.

If you do succeed in finding the Andromeda Galaxy it is worth considering that that small smudge contains thousands of each of the other types of objects we’ve been talking about. It was of course the astronomer Carl Hubble who first measured the distance to Andromeda proving that it is indeed another galaxy every bit as large as our own Milky Way. By the way, the word galaxy is just Greek for Milky Way.

As I mentioned in the first part of this post, much of what we now know about the Universe comes from studying all of these objects that Charles Messier cataloged so that he wouldn’t mistake them for the comets he was searching for.

I was inspired to write this article by a very good night of stargazing during which I managed to find and spend some time studying seven of Messier’s objects. It turned out that I also managed to spot the International Space Station as it flew over New Jersey, and it was followed the Cygnus unmanned resupply module as well so I got a good look at both of them!

I’ve seen the space station dozens of times now along with NASA’s space shuttle and the Soyuz space capsule. The station itself is easy to find if you know when and where in the sky it will appear for your particular location.

Hey, ya know, that might be a good idea for another post!

Charles Messier’s Catalog, What it is and How it gives us a Quick Survey of What Sort of Objects make up this Universe of Ours. Part 1 of 2.

(Note: This blog post turned out to be more than twice as long as my usual posts so I’ve split it into two. This is Part 1 and Part 2 will follow immediately.)

We’ve had some really clear skies here in Philadelphia the last few nights, just perfect for stargazing. Two nights ago I spent a good hour observing the four planets that are visible during the evening right now, Venus, Mars, Jupiter and Saturn. However last night I wanted to see some deep space objects. Star clusters, Nebula and Galaxies.

Problem is that the light pollution inside the city is so intense that you simply can’t see anything that faint. Oh, the planets and a few of the brighter stars are easy enough to see if you can just get away from the streetlights but the fainter, more interesting objects, well just forget it.

Typical Light Pollution in a City (Credit: Tes)

So I drove over to New Jersey, halfway to the ocean in fact, to a spot I know of where I can get some ‘Dark Sky’. After letting my eyes adjust I could see thousands of stars along with the Milky Way. Taking out my binoculars I spent the next hour observing seven of the objects from Charles Messier’s catalog.

What’s Messier’s catalog you ask? Well, let me tell you.

Born in 1730 Charles Messier was the son of a minor member of the French Court. Inspired by a very spectacular ‘seven tailed’ comet in 1744 Charles got a job working at the French Naval Observatory, in those days astronomy was very important in navigating around the globe. The image below is of Charles Messier.

Charles Messier (Painting by Nicolas Ansiaume 1729-1786)

At that time the cutting edge of astronomical research was comets. Using Newton’s law of gravity Edmund Halley had predicted in 1705 that the comet now named for him would return in 1758 and when it did all of Europe went comet crazy. During his lifetime Charles Messier is credited with the discovery of thirteen comets.

As Messier spent night after night searching for comets he often came across fuzzy, comet-like objects that didn’t move against the fixed stars as a comet would. Remember, comets may have very long, stretched orbits around the Sun, but they still orbit the Sun, they still move against the background of fixed stars. Anyway, rather than being constantly sidetracked by these comet-like objects Messier began to compile a catalog of them so that he, and other astronomers could ignore them.

Messier published the ‘final’ version of this list in 1784 with 103 objects cataloged. After Messier’s death in 1817 however researchers going through his notes found that he had discovered another seven objects so astronomers now recognize 110 objects as Messier objects.

Funny thing is, Messier complied his catalog so that he wouldn’t be distracted from his comet search by them. Today however astronomers are far, far more interested in the Messier objects than they are by comets. Messier objects come in six main types; open star clusters, globular cluster, gaseous nebula, planetary nebula, supernova remnants and finally galaxies. I’ll discuss each type using a well known example from Messier’s catalog.

Open Star Clusters (M45 the Pleiades): The easiest Messier object to find is the cluster of stars known as the Pleiades or ‘Seven Sisters’ that form a very small dipper on the back of Taurus the Bull. Although six or seven stars are visible with the naked eye binoculars will show over twenty and a good telescope reveal more than a hundred. The image below shows the Pleiades with the seven sisters named but you can easily see that there are many other stars in the group as well.

We now know that an Open Star Cluster is what happens when a gas cloud that has given birth to several hundred or even a thousand stars is dissipated by the energy being given off by those young stars. If the gas cloud is the stellar nursery then the open cluster is the star’s kindergarten. For several million years the stars in a cluster will travel together around the milky way but in time the gravitational pulls of the rest of the galaxy causes the stars apart to drift apart. So open clusters only last for a short period of time. Four and a half billion years ago our Sun must have been in an open cluster but the Sun’s brethren are now long gone.

Globular Clusters (M4, Globular Cluster near the star Antares): M4 may not be the biggest Globular Cluster but I’ve always considered it to be the easiest to find because it is so near Antares, the bright red heart of the constellation Scorpio. The name Antares means the rival of Mars and because of the star’s position near the plane of the ecliptic the planet and star do sometimes come close enough to rival each other. Once you find Antares look with binoculars just a short distance to the left and you’ll see a very pale, faint cotton ball. That is the globular cluster M4. See image below.

Globular Cluster M4 (Credit: European Southern Observatory ESO)

Globular Clusters are quite mysterious and very ancient. Containing hundreds of thousands or more than a million stars globular clusters last for billions of years. In fact it appears that many of the globulars in and around the Milky Way are actually older than the Galaxy is. Some astro-physicists speculate that globular clusters are the building blocks that form galaxies but in that case, how do globular clusters form?

Gaseous Nebula (M42, The Orion Nebula): We now know that gaseous nebula are in fact the gas clouds where stars are formed. The Hubble and other space telescopes looking into gaseous nebula in the infrared spectral region have now learned much about how stars form in such gas clouds. The Orion Nebula is a very easy example of a gaseous nebula to spot because I think the constellation of Orion is one of the easiest to spot. Once you’re found Orion look for the three stars of his belt. The Orion Nebula is just a short distance below the middle star of the belt. See image below.

I’m going to end for today right here. I’ll discuss the last three types of Messier objects in Part 2 of this post coming soon.

Space News for July 2018; Space X and Boeing Prepare for Unmanned missions for their Commercial Crew Capsules!

The big news this week is the arrival at Cape Kennedy of the first “spaceworthy” crewed version of Space X’s Dragon Capsule, see image below. This arrival is in preparation an unmanned test launch to be conducted later this year.

Space X Manned Version of their Dragon Capsule (Credit: Space X)

Know as Demonstration Module 1 (DM-1), the capsule had just finished two weeks of environmental tested at NASA’s Plum Brooke Station in Ohio. Here the DM-1 was placed in the facilities huge vacuum chamber and exposed to all of the hazards of a trip in Earth Orbit. In addition to a vacuum the chamber can also subject whatever equipment is being tested to either the intense, unfiltered sunlight or the absolute darkness of space, the extremes of heat and cold.

These tests were all conducted to verify that the DM-1 capsule is ready to take human beings into space as a part of NASA’s Commercial Crew Program which will take astronauts to the International Space Station (ISS). The fact that these tests were successfully completed in only two weeks is a good sign that the DM-1 is ready for its test mission later this year. The image below shows an unmanned Dragon supply capsule taking off on its way to the ISS, a preview of the forth coming DM-1 mission.

Launch of an Unmanned Space X Dragon Capsule (Credit: Space X)

While this first test mission will be unmanned it will still conduct a full mission profile, rendezvousing with the ISS and ending with a re-entry and splashdown, just as a manned mission would. The mission is currently slated to begin on August 31st 2018 but NASA has indicated several times that the launch date will probably be pushed back until sometime in the fourth quarter of the year with the first actual manned launch sometime in the first half of 2019.

Meanwhile Space X’s competitor Boeing is also making considerable progress in preparing their proposed manned capsule the Starliner, see image below. The Starliner’s initial, unmanned test flight is also still scheduled for August but it is also likely to be pushed back into the fourth quarter of the year.

Boeing Starliner Capsule (Credit: Boeing)

Part of the reason for the slippage is the already heavy schedule of launches at Cape Kennedy along with the already scheduled crew transfer and resupply missions to the ISS. Hopefully NASA will work out the scheduling conflicts while both Space X and Boeing finish preparing their capsules. NASA’s is soon going to run out of purchased tickets on the Russian Soyuz spacecraft so by next year the US will have no other way of getting into space.

There was also a second story this week which has a certain, it’s about time quality to it. The United Kingdom has just decided on the location of their spaceflight launch facility. Sixty years into the space age and Britain, one of the world’s most advanced nations, a leader in space technology has only now decided from where to launch its satellites.

There are a couple of very good reasons as to why the UK waited so long before getting into the satellite launch business. Britain is a small, densely populated country with little room from which to safely launch big rockets. Also most launch facilities, like Cape Kennedy and the European Space Agency’s launch site in Guyana, are close to the equator where the spin of the Earth can actually give a 1500 KPH start to any launch.

In recent years however, miniaturized satellites launched into polar orbits have become a sizeable slice of the space industry market and the UK wants to grab a piece of that pie. The chosen location of Sutherland on the A’Mhoine peninsula on Scotland’s north coast will allow rockets to be fired due north. This would place the satellite into an orbit that will allow the Earth to rotate beneath it so that eventually the entire planet can be observed by the satellite’s sensors. See the map below.

Sutherland County Scotland (Credit: Wikishire)

The UK Space Agency will build the launch facility with the help of the American firm Lockheed-Martin and hopes that the first launches will take place sometime in the early 2020s.

Paleontology News for July 2018

Since my last post (11July18) was a review of the new dinosaur movie Jurassic World: Fallen Kingdom I thought this might be a good time to discuss several items of interest in the field of paleontology. Since T-rex is one of the heroes of the Jurassic Park franchise, well at least to me, I’ll start with a recent discover about them.

The word dinosaur itself means ‘terrible lizard’ and the first scientists who studied their fossil bones did actually think of them as simply enormous lizards. Over the last two hundred years we’ve learned a great deal about just how different dinosaurs are from other types of reptiles and now a new study takes us another step further by examining dinosaur’s tongues.

Most representations of dinosaurs, including those in Jurassic Park, show dinosaurs as having tongues similar to those of lizards, long, only attached at the back and therefore able to stick out, pretty much the way ours do, see image below.

Old View of the Dinosaur Tongue (Credit: Spencer Wright)

According to Julia Clarke, professor of vertebrate paleontology at the University of Texas at Austin and co-author of the study however dinosaurs probably had a tongue more like those of the crocodiles and alligators. A tongue that was firmly attached to the bottom of the mouth along its entire length and one would be completely unable to stick outside of the mouth, see image below.

Dinosaur Tongue were actually more like those of a Crocodile (Credit: Shutterstock)

Since the soft parts of dinosaurs, such as tongues rarely survive the study based the study’s conclusions are based on an examination of the bones in the mouths of dinosaurs, in particular the hyoid bones that anchor and support the tongue. What the researchers found was that the short hyoid bones of dinosaurs more closely resembled the hyoid bones of the crocodilians rather than the hyoid bones of the lizards. So it turns out that we may have still been incorrectly thinking of dinosaurs as just big lizards.

One of the best known types of dinosaurs are the huge sauropods, the long necked, long tailed behemoths who were without doubt the largest animals ever to walk on Earth. Our modern whales may be as large but of course they swim in the ocean. See image of a brachiosaurus below.

The Brachiosaurus (Credit: Todd Marshall)

Now paleontologists working in Argentina have unearthed what they consider to be earliest known member of the sauropod group, and animal that they have named Ingentia prima. As might be expected for a very early member of a group I. prima looks a good bit different, see image below.

The Early Sauropod Igentia prima (Credit: The New York Times)

Comparing I. Prima to the brachiosaurus it’s easy to see that I. prima’s neck is a good bit shorter and while the legs of the brachiosaurus strongly resemble those of an elephant the legs of I. prima look more like those of theropod dinosaurs. To me the rear legs look a bit like the legs of T-rex.

I. prima lived during the Triassic period, about 215 million years ago, not long after the very first recognizable dinosaur evolved. While smaller than its later descents at an estimated ten tons and nearly ten meters in length I. prima was probably the biggest creature in the world at that time.

Paleontologists have long known that the huge sauropods evolved from much smaller, two legged dinosaurs and I. prima still shows some evidence of that two legged past. Researchers hope that further study of I. prima’s bones will give them further insight into how the sauropod group of dinosaurs evolved.

These studies are just two more examples of how, piece by piece, paleontologists are filling in the gaps in our knowledge of the history of life on Earth.

What is causing the Massive Die off of Bats in the Eastern United States?

For many years, one of my favourite things to do on a summer’s evening was to watch for the bat’s to come out about a half an hour after the Sun went down. To be honest I usually combined this with some backyard stargazing, but still the bats were certainly fun to watch. One of the most interesting parts was the timing, the bats always appeared just a few minutes after the last bird flew to its roost, never before, and never more than ten minutes after.

Over the last few years however my nocturnal flying friends have disappeared, along with millions of other bats throughout eastern North America and the cause has been identified as an epidemic of the fungus Pseudogymnoascus destructans, commonly know as White Nose Syndrome. The first image below shows a Little Brown Bat, Myotis lucifugus, that has been infected by white nose syndrome while the second shows the fungus itself.

Bat Infected with White Nose Syndrome (Credit: Marvin Moriarty / USFWS)

Fungus Pseudogymnoascus destructans (Credit: Gudrun Wibbelt et al)

Now P. destructans causes harm to bats in several different ways. The most obvious symptom is the fungal growth and lesions around the mouth and on the wings which inhibit the bat’s ability to eat and fly. The fungus is also known to infect the lungs causing respiratory distress.

However it is actually thought that White Nose Syndrome does its greatest harm by interfering with a bat’s winter hibernation. You see during hibernation bats, and other mammals as well, lower their body temperature in order to stretch body fat reserves throughout the winter. The fungus however prevents the bats from entering the torpor stage of hibernation, where the body temperature goes lower, and therefore the animals literally starve to death while trying to hibernate.

P. destructans was first spotted in a cave in New York state back in 2006 and has since spread to 33 states in the U.S. along with 5 provinces of Canada. The effect of the disease has been devastating with a decline of more than 90% in the bat population of caves where the fungus has been for over four years. By 2012, that’s six years ago now, 5-7 million bats are thought to have perished! The image below shows that areas of North American where White Nose Syndrome has been identified.

Present Extent of White Nose Syndrome in North America (Credit: Enwebb)

So where did White Nose Syndrome come from, how did it get here? The answer is simple, Europe. The fungus P. destructans has been known to infect European bats for decades but it seems that the European bats have acquired at least a partial immunity to the disease. It looks as if this is yet another example of a disease whose original population has evolved to survive, leaping into a related population with no immunity and causing a devastating epidemic. Well know examples of this phenomenon are smallpox among the Native Americans and Measles among the Hawaiian Islanders. And I’m afraid that once again Human Beings are probably the transmitters of the disease because it appears that people who like to explore caves, known as spelunking, can get the fungus on their clothing, which can then be passed to other caves they visit, even caves on different continents.

Spelunking, people having fun in a Cave (Credit: Phys.Org)

Now I know some of you are saying, who cares about bats? They’re icky anyway! Well remember that bats eat insects, a lot of insects and without bats we’re going to have a lot more destructive, disease carrying insects around! In fact the Forest Service estimates that 1.1 million kilograms of insects will go uneaten. That’s a lot of bugs eating our crops and spreading germs that infect people!

At the moment there is no known way of fighting White Nose Syndrome. There is research underway but only a little. There’s not a lot of funding to combat bat diseases. So, barring a providential discovery we can only hope that, like their European cousins, American bats will acquire the immunity to survive White Nose Syndrome.

Astronomers take First Ever Images of Planet being Formed around nearby Star, and how do Planets Form anyway.

By a strange coincidence, it was in 1633 CE, that the French Philosopher René Descartes first began to ponder how the Solar System was formed. Coincidence, because that was the very year that Galileo was tried by the Inquisition for supporting the theory that the Sun, and not the Earth stood in the center of the Universe.

Like Galileo, Descartes accepted Copernicus’ hypothesis that the Earth was a planet that circled around the Sun and not the Sun that circled the Earth. The Copernican picture of all of the planets orbiting around the Sun as if in a whirlpool led Descartes to speculate that originally the Solar System had formed from a vortex of swirling particles which condensed into the Sun and the planets.

Because Newton had not yet discovered his theory of Gravity, Descartes had no idea what had caused the condensation and because of his own fear of the Inquisition his ideas were only published after his death in 1664. Nevertheless Descartes basic idea of a rotating cloud that condenses turned out to be basically correct.

In was more than a century later in 1796 that the French Mathematician Pierre-Simon Laplace first attempted to construct a detailed model of how planetary systems formed. In addition to Newton’s theories Laplace also benefited from the observations of 18th century astronomers like Charles Messier and William Herschel who had discovered a large number of fuzzy, swirling ‘nebula’, in the night sky. To Laplace these nebula were Solar Systems in the process of formation, baby stars and planets. The images below show two of these ‘nebula’ the Andromeda (Messier Catalog M31) and the Triangulum (M33).

Triangulum Galaxy M33 (Credit: Space.com)

Unfortunately it turned out that many of those ‘baby solar systems’, in particular Andromeda and Triangulum were actually found to be other galaxies!!! Vast, huge collections of billions of stars. Other physicists soon discovered other problems with Laplace’s ideas as well so work on planetary formation stalled for about a century.

The Astronomer Forest Moulton in 1900 discovered one interesting fact about the Solar System that any theory of planetary formation must account for. It is simply that, while the Sun contains 99.8% of all of the mass in the Solar System, the planets contain 99% of the angular momentum. Throughout the early 20th century this simple fact became the downfall of several theories of how the planets formed.

It wasn’t until 1972 that the Soviet astronomer Victor Safronov revived the nebula theory of Laplace with his Solar Nebula Disk Model (SNDM). Safronov and his model received considerable attention when several young stars, such as Beta Pictoris, were found to be surrounded by disks of cool dust exactly as predicted by the (SNDM) theory.

Further observations by space telescopes such as the Infrared Astronomical Satellite and of course the Hubble Space Telescope have succeeded in discovering enormous ‘cosmic nurseries’ such as the Orion nebula (M42) and the famous ‘pillars of creation’ in the Eagle nebula (M16). See images below.

Pillars of Creation inside the Eagle Nebula M (Credit: ESA, Hubble)

Now astronomers using the Very Large Telescope at The European Southern Observatory have succeeded in looking deep into one of the disks of gas and dust that surround a baby star to see a baby planet in the act of forming. The baby planet is orbiting around a young orange dwarf star named PDS 70 at a distance from Earth of 370 Light Years. Looking at the image below the planet is the bright blog to the lower right of the black dot. The dot itself is a mask inserted in the telescope used to eliminate the light of the dwarf star which would otherwise overwhelm the faint light of the proto-planet.

PDS 70 Image showing Proto-Planet (Credit: Spacepage)

Astronomers at the Max Planck Institute who conducted the research had discovered a protoplanetary disk around PDS 70 back in 2012 which led them to attempt to image the proto-planet itself. Based upon their data the team, led by astronomer Miriam Keppler, estimate that the planet is about two to three times the mass of Jupiter orbiting its star at a distance of three billion kilometers, about the distance between Uranus and the sun.

Science works best when there is a strong back and forth between theory and observation / experiment. Our theories of planetary formation improve with every new observation while the new theories give the astronomers a better idea of what to look for in the sky!

Space news for June 2018.

Some really out of this world stories have taken place this past month. I think I’ll start with Jupiter, the king of the planets.

NASA’s Juno spacecraft has been studying Jupiter for over a year now, traveling on a highly elliptical polar orbit. That means part of its orbit passes very close above the planet’s poles while other parts of the orbit are at a much greater distance from Jupiter. The image below shows how a highly elliptic orbit works.

Highly Elliptical Orbit (Credit: Wikipedia)

One of the interesting aspects of the Juno mission is that NASA is releasing the raw images taken by the spacecraft’s cameras online and allowing citizen scientists to combine and enhance the images. Whether or not these amateur astronomers make any major discoveries they have certainly already produced some wonderfully artistic views of the planet. The image below, which rivals the best work of any avant garde painter, is the work of two such citizen scientists, Gerald Eichstädt and Seán Doran.

Jupiter Gas Clouds as Seen by Juno Spacecraft (Credit: Gerald Eichstadt, Sean Doran )

The Juno spacecraft is also helping to solve some long standing mysteries of the Solar Systems largest planet. For example, it’s been known for decades that lightning occurred in the planet’s atmosphere, some of which was far more powerful than any lightning here on Earth. Well, based on data sent back by Juno, the scientists at NASA have discovered that, while the lightning on Jupiter is generated in much the same way that it is on Earth, nevertheless the lightning on Jupiter is concentrated around the poles rather than being spread around the planet as it is on our planet. The image below shows a composite of many images of lightning captured by the Juno spacecraft.

Lightning on Jupiter (Credit: NASA, JPL)

Another spacecraft, the Japanese probe Hayabusa-2 has arrived at its destination the asteroid Ryugu after a 300 million kilometer journey that began back in December 2014. It didn’t take long for the Hayabusa-2 to make a major discovery for the asteroid has a very peculiar shape, that of a diamond, see image below.

Asteroid Ryugu (Credit: JAXA, University of Tokyo)

The spacecraft is expected to touch down onto the asteroid’s surface in an attempt to gather some material which is scheduled to be returned to Earth in late 2020. Hopefully that means that the spacecraft’s revealing of the asteroid’s shape is just the first in what will be a long series of discoveries.

Now you may remember that the Cassini spacecraft made its final plunge into Saturn’s atmosphere last September (See my post of 13September2017). However the data sent back by Cassini during it’s 13 years of exploring the ringed planet is still being analyzed so the spacecraft hasn’t finished making discoveries just yet.

One of the last maneuvers Cassini made before its final plunge was to actually pass through some of the material being ejected into space by the geysers it had earlier discovered on the moon Enceladus. These geysers are believed to be liquid water that was heated by the tidal friction between the moon, the planet Saturn and the larger moon Titan. (Much the same thing is believed to happen on Jupiter’s moon Europa) The image below, taken by Cassini, shows the geysers.

Geysers erupting on Saturn’s Moon Enceladus (Credit: New Scientist)

Now NASA has announced that their scientists have found evidence of complex organic molecules in the material Cassini passed through. This discovery increases dramatically the chances that some form of life may exist in an ocean under the protective ice cover enveloping the moon.

Finally Space X just seems to keep on adding on to their long string of space successes. Today’s launch of a Falcon 9 rocket with its Dragon capsule not only marked the beginning of Space X’s 15th resupply mission to the International Space Station (ISS) but was also a reuse of both the Falcon 9’s first stage and the Dragon capsule. Indeed the booster first stage had be used only ten weeks ago to launch NASA’s Transiting Exoplanet Survey Satellite (See my post of 28April2018) making this the fastest turnaround of a reusable first stage ever. The image below shows the launch of the Falcon 9 / Dragon capsule.

Space X launch of 29 June 2018 (Credit: Daily Express)

To date Space X has succeeded in recovering 25 Falcon 9 first stages and has reflown 14 of them in the company’s effort to reduce the cost of space travel by developing reusable launch vehicles and capsules. Space X did not attempt to land the Falcon 9 first stage after today’s launch however because the company is phasing out its ‘block 4’ design in favour of the new ‘block 5’ boosters which are optimized for reuse.

Also, in just a few months, Space X is scheduled to conduct the initial, unmanned test flight of what will become its crewed Dragon capsule. I can’t wait for that!

Chemists Develop Technique to Recover Early Photographic Images that have been Degraded over Time, and a bit about the History of Photography.

Nowadays most of us carry a camera with us wherever we go. The cheap little digital cameras in our phones can capture images that are often superior to the images taken 50 years ago by professionals using the best equipment of their time. It’s hard to imagine that photography is only a little more than 200 years old and that it was once a very difficult combination of art and science.

The word camera itself is Latin for room and really applies to the box which light can only enter through a pinhole opening. Such a device is known as a ‘Camera Obscura’ and way back in ancient China it was found that the light coming through the pinhole would project an inverted image on the opposite side of the box. See the image below for a diagram of the operation of a Camera Obscura.

How a Camera Obscura Works (Credit: Public Domain)

It was in the year 1800 that Thomas Wedgwood attempted to capture the image in a Camera Obscura by means of a sheet of paper that had been soaked with the light sensitive chemical silver-nitrate. Wedgwood did succeed in making a shadowy image however the silver-nitrate was so unstable that the image faded after only a few days.

It was the Frenchman Nice’phore Nie’pce who placed a lens where the pinhole had been and produced the earliest surviving photograph in 1826. Known as ‘The View from the Window at Le Gras’ the image took several days exposure to complete, that’s how much light was needed to alter the silver nitrate. The image of “The View from the Window at Le Gras’ is below.

The Earliest Surviving Photograph (Credit: Public Domain)

Obviously photographs that required hours or even days to produce were not going to be a big commercial success. It wasn’t until 1839 when Louis Daguerre discovered a way to make the images formed by using silver halides permanent that photography became more than just a science experiment. Daguerreotypes as they were known were produced in the thousands with many historical and artistic firsts. These include the first photographs of world leaders, see the earliest known photo of Abraham Lincoln below, and the first photograph of a Solar Eclipse, taken on July 28, 1851 and also shown below.

Earliest Photograph of Abraham Lincoln (Credit: Public Domain)

First Photograph of a Solar Eclipse (Credit: Public Domain)

Even Daguerreotypes fade in time however, and today some of the oldest known photographs are so degraded that their images are all but lost. Lost that is, except for the work of researchers at Western University and the National Gallery of Canada. Led by Madalena Kozachuk, a Ph.D. student at Western’s Department of Chemistry the researchers used rapid-scanning micro-X-ray fluorescence to measure the Daguerreotype’s remaining mercury, used in the development of the image after exposure.

By making a point by point measurement, taking eight hours to complete, Kozachuk succeeded in restoring the images. Looking at the side by side comparison below of a Daguerreotype of an unknown woman it is easy to see how well the process works.

Original (left) and Restored Photo of a Woman (Credit: Madalena Kozachuk)

There are thousands of Daguerreotypes stored in libraries around the world; the National Gallery of Canada itself has over 2,700. Madalena Kozachuk’s technique allow enable conservators to bring back some of our earliest photographic history.

Think about that the next time you pull out your smartphone and start snapping some selfies!

Unusual Form of Chlorophyll found to produce Photosynthesis using Infrared Light.

We all know the basic facts about photosynthesis, or at least we all think we do. Plants use the chemical chlorophyll to absorb sunlight and use its energy to turn carbon dioxide and water into sugar. This chemical process is called photosynthesis and is the main source of food for all life on Earth. At the same time photosynthesis also produces oxygen as a by-product. So for us animals photosynthesis provides both the food we eat as well as the oxygen we breath. Oh, and chlorophyll is also the reason plants are green. See image below of plant cells, the green blobs are called chloroplasts where the chlorophyll is concentrated.

Chlorophyll in Plant Cells (Credit: Wikipedia)

As you might guess, chlorophyll is a rather complicated chemical and not surprisingly there are several variant forms of the chemical. Looking at the chemical diagram below for chlorophyll-a the most common form, the roundish structure on the right hand side is called the chlorin magnesium ligand, which is shared by all forms of the chemical.

Chemical Diagram of Chlorophyll (Credit: Wikipedia)

Biochemists have identified six other slight, yet still distinct variant form of chlorophyll. These are labeled chlorophyll-b through -f with two different c’s, -c1 and -c2. Each of these variant chlorophylls absorbs different wavelengths of visible light more or less efficiently than the others with Chlorophyll-a generally being the most efficient, which is why it is by far the most common type. The image below shows the absorption efficiency versus wavelength for chlorophyll-a and chlorophyll-b.

Absorption Comparison of Chlorophyll-a vs. Chlorophyll-b (Credit: Wikipedia)

Of course there are wavelengths of light that are outside the visible spectrum. Infrared light is one of these and researchers have now discovered that chlorophyll-f is particularly good at using the energy of infrared light in what is being called ‘a new kind of photosynthesis’. In fact, under low light conditions photosynthesis using chlorophyll-f becomes dominant in certain species of cyanobacteria and blur-green algae.

These bacteria and algae are examples of life in extreme conditions, many live deep underwater in the boiling hot volcanic springs of Yellowstone or similar hostile environments. The ability to get energy from light that other ‘more advanced’ living things can’t use gives these single celled creatures the advantage they need to survive.

Life forms that can life in such extreme conditions are of great interest to space scientists who want to understand what life on other worlds, with very different environments, might be like. In fact Mars, further from the Sun with lower levels of light, might be the perfect environment for bacteria using the chlorophyll-f style of photosynthesis.

Some scientists have gone even further and are already suggesting that such bacteria be taken from Earth to Mars in order to start producing oxygen that one day people might breath. Importing and spreading such low light using, oxygen producing bacteria across the planet would be one of the first steps in Terraforming Mars for human habitation.

I’m certain that there’s still a great deal more to be learned about chlorophyll and the process of photosynthesis just as I’m certain scientists will keep studying it. And maybe someday soon we will find life on Mars or Europa or elsewhere and we will get the chance to learn how true aliens produce their food.

Archaeology News for June 2018, better precision for Carbon 14 dating in the Middle East and a Spectacular find whose date could be effected.

Starting in the 1950s the science of Archaeology was revolutionized by the use of radioactive carbon-14 as a means of giving precise, hard dates to objects discovered during archaeological digs. Like any measuring tool however, carbon-14 (¹⁴C) dating has been, and continues to be improved in order to make its measurements more accurate, more precise and more reliable. Now a new study from researchers at Cornell and Oxford Universities seeks to further improve the accuracy of ¹⁴C dating for the Middle Eastern region by comparing it to the dates obtained by examinations of tree rings.

To understand the significance of the study let me take a few minutes to describe what ¹⁴C is and how we use it to date things. If you remember from you high school chemistry all atoms are made up of particles called protons, neutrons and electrons. The protons and neutrons reside in the very center of the atom, which is called the nucleus while the electrons fly around the nucleus. In a neutral atom the number of protons and electrons is equal and it is that number that determines what kind of atom, what chemical element it is. For example an atom of carbon has six protons and six electrons.

The number of neutrons can vary, but if the nucleus has too few, or too many neutrons it will be radioactively unstable. For carbon the stable number of neutrons is either six, making carbon-12 (¹²C) which makes up almost 99% of the cosmic abundance, or seven making carbon-13 (¹³C) at a little over 1%.

With eight neutrons carbon-14, (¹⁴C) is radioactive with a half-life of 5568 years. This means that if you had a thousand atoms of ¹⁴C in 5568 years you would only have 500 atoms of ¹⁴C left. Then in another 5568 years (11136 years total) you would only have 250 atoms of ¹⁴C. This having goes on every 5568 years until the ¹⁴C is gone. The image below shows the decay of a ¹⁴C atom.

The Decay of Carbon -14 (Credit: Science Blogs)

But if ¹⁴C shrinks by half in just a few thousand years, how is there is any left? After all the Earth is billions of years old isn’t it? Shouldn’t the ¹⁴C be all gone by now?

It would have, if not for the solar wind striking the top of our atmosphere which produces a small amount of ¹⁴C all of the time. This trace of ¹⁴C drifts down into the lower atmosphere where it is absorbed into plants during photosynthesis. The image below shows the reaction that produces ¹⁴C.

The Production of Carbon-14 (Credit: Science Blogs)

Animals, like us, then eat the plants so some radioactive ¹⁴C gets absorbed into our bodies. (That’s right, you are radioactive. Well a little bit!) The ratio of ¹⁴C to ¹²C can be measured. When the animal or plant dies the ¹⁴C begins to decay, half of it disappearing every 5568 years. If you measure the ratio ¹⁴C/¹²C in organic material you can calculate how long it’s been dead! This was what scientists first thought 70 years ago.

Turns out it wasn’t quite that easy. You may also remember from high school that the Sun has an eleven year Sunspot cycle and that cycle, along with other factors alter the amount of ¹⁴C produced each year leading to some small inaccuracies. Because of this scientists have done a lot of work over the years in order to develop calibration factors that improve both the accuracy and precision of ¹²C dating.

The new study is one such attempt at a better calibration. The study consisted of taking samples from tree rings of a historically known date. For example if a building in Jerusalem is documented to have been built in 1830, wood used in its construction would have been cut down in 1829 and if you count in 100 rings from the last ring you then have material from the year 1729. Measuring the age of that material using ¹⁴C and by comparing that date to 1729 you get a calibration of ¹⁴C dating in Jerusalem.

That’s a part of the issue, the study from Cornell have found discrepancies between ¹⁴C dates in the Middle East and similar studies in other parts of the northern hemisphere. The researchers have found an average of a 19-year variation over the period 1610 to 1940CE. They speculate that the reason could be tied to the fact that the growing season for agriculture in the Middle East is actually during the winter rather than the summer as in Europe and Asia. The question is however, if the dates from 400 years ago are off by 19 years what about the date of something from say 3,000 years ago?

That would be nice to know because as it happens a very important find has recently been dug up at the archaeological site Abel Beth Maacah in northern Israel. The find is a 5cm tall figure of the head of a man, see image below. The head is made of a glass like material called faience and is almost certainly that of a high noble if not a king.

Figurine of head of a biblical King? (Credit: Fox News)

The find has been ¹⁴C dated to the 9th century BCE when a village called Abil al-Qamh was the crossroads of three biblical kingdoms, Tyre, the Aramean kingdom based in Damascus and Israel itself. In fact Abil al-Qamh is mentioned several times in the bible and based on the ¹⁴C date it has been suggested that the figurine may in fact be that of the well-known biblical king Ahab or that of his son Jehu. However it is just as likely that the head could be that of the Aramean king Ben Hadad or king Ithobaal of Tyre. Each of these men are mentioned in the bible so a definite identification as any one of them would be a discovery of historical as well as archaeological importance.