Astronomy – Scienceandsf -A Blog Published by Robert A. Lawler

A Citizen Scientist discovers what could be the first of a new class of Brown Dwarfs. And what are Brown Dwarfs anyway?

Most people know that our Sun is pretty much a middle of the road star. Any star that is much more than 20 times the mass of our Sun is so big and unstable that it doesn’t last for very long. And any astronomic body that has much less than 1/20th our Sun’s mass won’t have enough pressure and temperature in its core to ignite hydrogen fusion, so they never shine as a star. Jupiter for example is the most massive of the planets, but since it only has 1/1000th the Sun’s mass it is a planet, not a star.

Our Sun, which is a middle sized star is about 1,000 times as massive as the large planet Jupiter. We now known that there are objects in between that we have christened ‘Brown Dwarfs’. (Credit: NASA)

Beginning in the 1960s astronomers began to wonder if there could be objects out in the galaxy that were too small to be stars yet too big to be planets, a class that was eventually given the name Brown Dwarfs. Such objects would have masses in the range of 10-80 times Jupiter’s mass and are often described to be ‘failed stars’.

Brown Dwarfs are too big to be planets but still aren’t massive enough to ignite nuclear fusion in their cores making them ‘failed stars’. (Credit: EarthSky)

Since they don’t shine in visible wavelengths like real stars, and the closest could be light years away Astronomers knew that Brown Dwarfs were going to be very difficult to find. Brown Dwarfs wouldn’t be totally dark however, even the smallest would have some heat left over from their formation while the heaviest could even have a small amount of heavy hydrogen, that is deuterium fusion going on inside them. Because of this Brown Dwarfs would be visible in infrared (IR) light.

There’s no reason why a Brown Dwarf couldn’t have a planet orbiting them but at the moment we’re having enough difficulty just finding Brown Dwarfs. (Credit: Owlcation)

Infrared astronomy is difficult here on Earth’s surface however, because even a tiny amount of water vapour in the air blocks IR light. In the 1960s there simply weren’t any IR telescopes and it wasn’t until the 1990s that a few IR space telescopes were launched into orbit and the first IR telescopes were built on the tops of the highest Andes Mountains, the driest place on Earth.

The high Atacama desert in the Andes mountains of Chile is the best place on Earth to do infra-red astronomy. (Credit: Aura Astronomy)

In 1988 a star designated as GD 165 was discovered to have a very small companion star, designated as GD 165B, during a search for white dwarf stars. The light of GD 165B was barely in the visible red portion of the visible spectra and astronomers wondered if it might be the first known Brown Dwarf. The debate over GD 165B’s status continued for almost a decade until new telescopes conducting the Two Micron All Sky Survey (2MASS) discovered over a hundred similar objects, and so Brown Dwarfs became a new class of celestial object.

What the Universe looks like at a wavelength of 2 Microns courtesy of the 2 Micron All Sky Survey (2MASS) (Credit: Infrared Processing and Analysis Center – Caltech)

Today Brown Dwarfs have been classified into two spectral types, both below the familiar O, B, A, F, G, K, M classes of normal stars. The larger Brown Dwarfs, which have a strong lithium line in their spectra, are classified as “L” type. Since true stars burn their lithium very quickly the presence of lithium in a spectra is indicative of a brown dwarf.

Normal stars are classified by their surface temperature as O, B, A, F, G, K, or M types with O being the hottest and M the coolest. Brown Dwarfs add two new classes L and T to the right. (Credit: SDSS SkyServer)

In time some brown dwarfs were discovered whose surface temperatures were cooler than the L type, so cool that methane was discovered in their spectra, even L type dwarfs are too hot for chemicals to exist. So a new class of Brown Dwarf, the “T” class was created. Presently astronomers have identified nearly a thousand L type and about 350 T type Brown Dwarfs.

Two classes of Brown Dwarfs are recognized by all astronomers while a new classification “Y” is still being debated. (Credit: Backyard Worlds)

Since Brown Dwarfs generate little if any energy by fusion they really have no stable “Main Sequence” period in their lives but instead just continue to get cooler and cooler, eventually becoming so cool that they no longer even radiate in IR wavelengths. For that reason it was thought that it would be very difficult if not impossible to detect a Brown Dwarf that was more than a few billion years old.

But they may just have found one by ‘Accident’, or at least citizen scientist Dan Caselden seems to have found one and his finding it really was an accident. Caselden had written a computer program to search for Brown Dwarfs in the data collected by the Near Earth Object – Wide field Infrared Survey Explorer (NEO-WISE) satellite. In particular Caselden was looking for objects so close to our solar system that they would appear to move slightly against the background of more distant starts over the course of six months or a year. (NEO-WISE conducts a complete survey of the entire sky every six months)

The Wide-field Infrared Survey Explorer (WISE) satellite has been given a new mission to search for Near Earth Objects (NEOs) making it now the NEO-WISE mission. (Credit: Wikipedia)

Caselden was checking out one candidate for a close Brown Dwarf when he noticed another object nearby that was moving even faster. Its spectra didn’t look like that of a Brown Dwarf but Caselden decided he’d check it out.

By day a Security Engineer in his spare time Dan Caselden is a new breed of computer astronomers. Seriously all of the satellites we’ve put into space are sending back so much data that even ordinary people, with a computer, can make important discoveries. (Credit: NASA Solar System Exploration)

Caselden’s discovery has now been given the official designation of WISEA J153429.75-104303.03 but it’s also known by its nickname of Accident. When examined more closely by powerful ground based telescopes Accident was found to be as cool as a T type Brown Dwarf but there was no trace of methane in its spectra. In fact there was no trace of carbon or any of the more massive elements like oxygen or sodium or iron. WISEA J153429.75-104303.03 appears to be made entirely of the elements hydrogen and helium.

If you’re interested in being a citizen scientist try checking it out on YouTube. (Credit: Twitter)

That would indicate that Accident is old, very old, ten billion years old or older. You see, shortly after the big bang, when the first galaxies began to form the matter in the Universe was almost entirely hydrogen and helium. The heavier elements, like those that make up planets and even our our bodies were created inside the nuclear furnaces of the first generation of stars some 10 to 13 billion years ago.

The first stars began to form only 100 million years after the Big Bang. At that time only the elements Hydrogen and Helium existed in any amount so the elements that formed the planets, and our bodies were forged in the cores of those first stars. (Credit: Futurism)

So Accident may be a Brown Dwarf that was formed at the same time as the very first stars. If that is so then WISEA J153429.75-104303.03 may hold secrets within it that relate to how the first stars and galaxies came into being. WISEA J153429.75-104303.03 could even be the first in an entirely new class of Brown Dwarfs. So I guess it will be no accident if astronomers pay a great deal of attention to it in the years to come.

Accident brings another question to mind. Just how many Brown Dwarfs are there out there in our galaxy? So far we have only found around two thousand but they are all rather close, within 100 light years. We are still only beginning to get a feel for how common they are.

Many of the Brown Dwarfs we know about are companions of more normal stars such as this one. (Credit: Universe Today)

We do know that there are a lot more middle sized stars like our Sun than big, bright ones like Vega, and there are a lot more small, dim stars like Barnard’s star or Proxima Centauri than middling stars like our Sun. If you extrapolate from those facts then there could be a lot more Brown Dwarfs in the Milky Way than all of the real stars put together.

On a clear night you can see thousands of nearby stars but how many Brown Dwarfs are out there that we can’t see? (Credit: Space Tourism Guide)

Think about that the next time you go out on a nice clear night to gaze up at the heavens.

Astronomers succeed in taking first Picture of a Black Hole

First Picture of a Block Hole (Credit: Event Horizon Telescope Collaboration)

Yes it’s true; you can’t see a black hole. The glowing doughnut shape in the image above is actually the swirling mass of gas and dust that is falling into the black hole. Astronomers call that whirlpool an accretion disk and the energy released by that matter as it drops into the gravitational well of the black hole causes the disk to glow. Also, the actual image that you see above wasn’t really taken in visible light. Rather it’s a computer-generated image converted from measurements of radio emissions across the region around the black hole.

In fact it took eight radio telescopes and more than three hundred astronomers working together in a group known as the Event Horizon Telescope Collaboration to collect the signals from the black hole needed to construct the image. The eight radio telescopes which make up the Event Horizon Telescope (EHT) are spread around the half the world; see map below. By combining the received signals of those telescopes the astronomers succeeded in constructing a single radio telescope whose resolution was equivalent to a telescope that would be nearly the size of the Earth. (The resolution of a telescope is its ability to separate two objects that are both very far away and very close together.)

The Eight Radio Telescopes that were combined to produce the Black Hole Image Span half the World (Credit: EHT)

The technique used to combine the eight signals is know as Very Long Baseline Interferometry (VLBI) and networks the telescopes by adding their signals together, allowing them to interfere with each other, remember these signals are waves, exactly as they would in a telescope as big as the distance between the telescopes. In order to add the signals together properly they must have been received at precisely the same time. This means that each radio telescope in the EHT must be governed by its own atomic clock, and all eight atomic clocks must have been synchronized before the first signals were received.

The Combined Array for Research in Millimeter-wave Astronomy (CARMA) is just one of the eight telescopes that make up the Event Horizons Telescope (Credit: University of Chicago, Department of Astronomy and Astrophysics)

That degree of precision was necessary because the black hole whose image was taken sits 55 million light-years away in the galaxy known as M87 or Virgo A and the size of the black hole is about the same as the orbit of Pluto while the size of the accretion disk is about eight times larger. In addition to producing the image the measurements made by the EVT allowed a more precise measurement of the black hole’s mass, a whopping 6.5 billion times the mass of our Sun.

The Galaxy M87 which contains the first Black Hole ever Images (Credit: The Daily Galaxy)

All that work was certainly worth the effort. That one image confirms much of the theoretical work that has been conducted regarding black holes over the last thirty to forty years. The black hole’s event horizon, the energy emitted by the accretion disk as matter flows into the black hole, they’re all there, just as the models predicted.

What the Theories said a Black Hole looked like. Turned out they were Right! (Credit: Science)

The importance of the image is that it confirms one of the strangest predictions of Einstein’s General Theory of Relativity, the very existence of black holes. Now however, the researchers hope to use the EVTC to probe closer to the event horizons of black holes in order to test the limits of the General Theory. Even after one hundred years physicists have still been unable to integrate General Relativity with Quantum Mechanics, the other great theory of modern physics. The possibility that observations of black holes by the EVT may discover some clue leading to that unification is very enticing.

The astronomers also hope to learn more about the supermassive black holes that sit in the center of every galaxy. At the moment we don’t even know for certain which comes first, the galaxy or the black hole in its center but there are theories of galactic evolution that start in both directions. Maybe EVTC will find the evidence to answer that question.

As their next step the members of the EVTC are planning on trying to obtain images of the black hole that sits at the center of our own galaxy. Since our black hole is a lot closer, only 30,000 LY away you might wonder why the astronomers didn’t start with our black hole. You have to remember however, that to see the center of the Milky Way you have to look through most of the galaxy’s disk. In other words that black hole may be closer but there’s a lot more stuff in the way!

Looking towards the center of the Milky Way there’s a lot of other stuff between us and that Black Hole (Credit: Harvard CfA)

So the first image of a black hole that was taken by the EVT is really just a first step. There are many black holes to be studied out there, which means many more discoveries just waiting for the EVT to make.

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!

Is an Alien Supercivilization Causing Taby’s Star to Flicker?

Two years ago the star KIC 8462852, also know as Taby’s star created a bit of a sensation in the press and all over the web. The reason for all the excitement was the suggestion that the star’s irregular light curve, the amount of energy generated over time, could be explained by the existence of an ‘Alien Megastructure’ built around the star. Well Taby’s star is acting up again and we still know very little about the cause.

Let’s start with a few things we do know for certain. First of all KIC 8462852 is an F spectral type star in the constellation of Cygnus. Now the F spectral class is the next class bigger and brighter than our Sun, which is spectral class G. Taby’s star is in fact estimated to be about 1.5 times as massive as our Sun and about 5 times brighter. Despite its brightness however, at an estimated distance of 1300 light years Taby’s star cannot be seen with the unaided eye. The picture below shows Taby’s position in our sky.

In many respects KIC 8462852 should be just an average, normal main sequence star, a star as stable and constant as our own Sun. Taby’s star is anything but stable however, its brightness has been observed to drop by as much as 22% and even after years of observations astronomers have been completely unable to find any pattern in the variations of its light. The picture below shows KIC 8462852’s light curve for the 17th of April in 2013 as measured by the Kepler Space Telescope.

Several possible mechanisms for the variations in KIC 8462852’s brightness have been suggested. A system of one or more planets passing in front of the star can produce small and periodic dips in brightness; in fact this is how the Kepler space telescope has succeeded in discovering hundreds of planets outside our solar. However KIC 8462852 has larger reductions in it’s light output than could be caused by a planet, as much as 22% remember.

Other possible explanations include a swarm of asteroids or giant planets ‘flying in formation’ in highly eccentric orbits that sometimes bring them close to the star and other times take them far away from it. If the idea of three, four or more Jupiter sized planets orbiting as a group seems unlikely, well many astronomers agree with you. Bare in mind though, that astronomers have examined the light curves of millions of stars by now so it’s quite possible that Taby’s star is that one in a million oddball.

A recent suggestion has been made that the fluctuations in the light output from KIC 8462852 may be due to the star’s having swallowed a planet a couple of thousand years ago and in a sense its stomach is still upset.

Finally we have the proposed explanation that has everyone talking. There is a definite possibility that an alien supercivilization is building a structure similar to one described by Physicist Freeman Dyson and known as a Dyson Sphere. The idea of a Dyson Sphere is simple, in fact it’s the ultimate in solar power. By enclosing a star in a sphere an advanced civilization would have access to its entire energy output.

In this scenario the aliens are in the process of building the Dyson sphere around KIC 8462852 so that at present it is only capturing a small portion of the star’s total energy. This would still be more energy than the human race has used in its entire history.

All these possibilities are just that however, possibilities. We need more and more careful observations before we can make any kind of definite statement about the cause of the irregularity of Taby’s star. Since KIC 8462852 is now once again varying in brightness maybe soon we will learn more.

Before I go I do want to say one more thing. While much of what we know about KIC 8462852 comes from the Kepler space telescope or other professional observatories much of it has also come from observations by amateur astronomers. Throughout history these scientific hobbyists have discovered much of what we know about the Universe by their searches for comets or asteroids or by their measurements of the light curves of variable stars like Taby’s star.

Searching for ET on Wolf 1061c

Over the past two decades astronomers have had a field day discovering new planets orbits other stars within our galaxy. As of the beginning of 2017 more than 3500 extrasolar planets have been discovered, enough to give astronomers a good statistical sample of how many planets are out there, and what kind.

Those planet’s which orbit their star in the ‘habitable zone’ where liquid water can exist on their surface have received extra attention because of the possibility that life may exist on them. Such planets are neither too close to their star nor too distant and are often referred to as Goldilocks planets. Wolf 1061c is one such planet and at a distance of 13.8 light years it is one of the closest.

Astronomer Stephen Kane of San Francisco State University is presently conducting an extensive examination of Wolf 1061c to learn all we can with our present technologies while at the same time preparing for further studies as new instruments come on line.

The parent star of Wolf 1061c is a small red dwarf star whose energy output is only 0.15% that of our Sun. This means that the planet must orbit very close to it’s star in order to receive enough sunlight to warm it’s surface. The planet itself has a mass of an estimated 4.25 times that of our Earth so it may have a much stronger surface gravity.

Also, Wolf 1061c is the middle of three planets known to orbit Wolf 1061. All of them are believed to be rocky worlds more massive than Earth and because the entire Wolf system is so small the three planet’s gravities interact with each other making their orbits change considerably with time. Professor Kane warns that this could mean that the climate on Wolf 1061c may be quite chaotic. While none of this makes Wolf 1061c sound like a good spot for a vacation home you should remember that life is very adaptable and the inhabitants of Wolf 1061c might find our Earth to be unbearably dull.

Professor Kane hopes to learn even more about Wolf 1061c when the new James Webb space telescope is launched in October of next year (2018). The examination of nearby extrasolar planets is one of the jobs the Webb telescope was designed to carry out so we should soon know even more about Wolf 1061c. The last two decades have been very interesting times for the planet hunters and let’s hope that the next two decades are even more exciting. To learn more about Professor Kane’s work the link below will take you to San Francisco State University’s news story about Professor Kane.

http://news.sfsu.edu/news-story/sf-state-astronomer-searches-signs-life-wolf-1061-exoplanet

Astronomer Predicts a Nova Eruption for first Time

Scientists make predictions, that’s how we know that our models are correct. If we can forecast that something will happen before it happens we must have a good idea of just what’s causing it to happen.

In my blog back on January the first I mention the total solar eclipse that’s going to happen on the 17th of August of this year and scientists have been predicting eclipses now since the time of the Roman emperor Claudius.

A few predictions have been some of the greatest moments in the history of science, such as when Edmund Halley predicted that a comet would return or when Paul Dirac predicted the existence of Anti-matter. Just a few years ago the discovery of the Higgs boson confirmed a prediction made by Peter Higgs back in the 1960s.

Now Astronomer Lawrence Molnar of Calvin College in Grand Rapids Michigan is making the first ever prediction of the eruption of a Nova, the explosion of a particular star system. The star system in question is called KIC 9832227, a 12th magnitude system in the constellation in the of Cygnus. The system consists of three stars, two of which form a contact binary, that is two stars that are so close to each other that they are “kissing”. See picture below.

Star Merger Geometry. L. Molnar, Calvin College

Professor Molnar and his team have been studying KIC9832227 for many years now and have noted an acceleration in the orbit period of the two stars, an acceleration which is increasing exponentially. Based on these observations Professor Molnar predicts that in 2022, give or take a year the stars will merge into one and that the resulting explosion will make the 12th magnitude system temporarily visible to the naked eye, a new star or Nova will appear briefly in our night sky.

While not as spectacular as a Supernova, where a star 10 or more times as massive as our Sun explodes in a fireball as bright as an entire Galaxy this is the first time anyone has been bold enough to predict a date on when a nova will occur. I hope that five years from now I get to see KIC 9832227 as it goes Nova. If it does Professor Molnar will have joined the ranks of Halley and Dirac and many others whose predictions have done so much to advance human knowledge. You can read an article on Professor Molnar’s work at Sky and Telescope Magazine by clicking on the link below.

http://www.skyandtelescope.com/uncategorized/stars-en-route-to-merger/

Before I go I want to also mention a new, and I think very beautiful picture of our Earth with the Moon that has been taken from orbit around Mars by NASA’s Mars Reconnaissance Orbiter.

Earth and Moon as seen from Mars- NASA Picture

If you’d like a better picture check out the article at Space.com by clicking below.

http://www.space.com/35252-earth-and-moon-from-mars-photo.html

P.S. I finally got around to making a unique header image for Science and Science Fiction. I hope you like it!

These are a few of My Favourite Things

I assume anyone who visits this blog, or at least anyone who comes back, has an interest in science, space and astronomy. With that in mind I thought I’d take a moment to tell you all about some of the web sites I like to visit, these are a few of my favourite things.

I guess the best place to start would be NASA’s main page. Now this page is pretty general, intended for students and the general public but it does allow you to access to information on every mission NASA has ever undertaken. Seriously, there’s a lot of good stuff to be found here.

http://www.nasa.gov

Another NASA site, which actually isn’t easy to get to from their main site, is “How to spot the Station” which allows you to get detailed sighting information to find the International Space Station as it flies over your head. I’ve seen that station now over thirty times and it’s always pretty cool

http://spotthestation.nasa.gov

And if you like NASA you’ll love the Jet Propulsion Labouratory (JPL) in California. Their main page is also general interest but again, if you look around there’s a lot to see.

http://www.jpl.nasa.gov

JPL also has a really cool site that’s hard to get to from their main page. This is the small body database. Orbital and physical parameters for thousands (it’s growing all the time) of small asteroids and other objects in our solar system. It takes a little bit of figuring out but I really love the orbital diagrams, especially for Near Earth Objects (NEOs). Caution, the orbital applet is JAVA enabled so you need JAVA on your computer.

http://ssd.jpl.nasa.gov/sbdb.cgi

There are now several commercial sites that are also worth checking out on occasion. The best known is Space.com which is a news site dedicated to the latest happenings in space.

http://www.space.com

A new one, as far as I know, is Spaceflight insider. This site also has space news but it also has a launch calendar of upcoming launches from around the world.

http://www.spaceflightinsider.com

One last cool space site is SpaceWeather.com. Yes there is a web site dedicated to giving you the latest weather report from our solar system. A couple of interesting things to see here are the latest sun spot report, the solar wind and cosmic ray intensities and near Earth asteroid approaches during the next month.

http://www.spaceweather.com

Now let’s change course a little bit and look at some astronomy sites. I guess a nice segue would be the main web site for the Hubble space telescope. You can spend days just going through the beautiful images.

http://hubblesite.org

One of my favourite sites is the SEDs Messier data. Charles Messier was a French astronomer about the time of our revolution who was studying comets. Well he made up a list of fuzzy objects that weren’t comets. The objects on that list turned out to be galaxies and nebula and star clusters and supernova remnants. The SEDs site has tons of beautiful images of these objects.

http://messier.seds.org

A daily astronomical note of interest can be found at Stardate.org by the McDonald Observatory in Texas. They often have information on things to see in the sky tonight.

http://stardate.org

Another observatory with a cool web site is Keck in Hawaii. Again plenty of beautiful images.

http://www.keckobservatory.org

A great commercial site is Sky and Telescope magazine. The best part of their site, as far as I’m concerned, is the interactive sky chart which can show you what the sky will look like anywhere in the world not just for tonight but for any night for the next hundred years. Oh, and the last hundred years as well. Lemme tell ya, I’ve planned many nights of stargazing using that site. This is also a great place to look for telescope and accessories to buy.

http://www.skyandtelescope.com

This getting to be a bit of a long post so I think I’ll save Physics and Paleontology and Archeology for a later date. I have one more site for today and it’s possibly the most interesting. Back in the 1960s Jodrell Bank Radio observatory in Manchester England discovered the astronomical objects know a Pulsars. Well Jodrell Bank has a web page where you can hear, that’s right hear the sound of collapsed stars only a couple of kilometers across that are spinning so fast that they generate a magnetic field so huge it shoots out a radio beam like a searchlight and every time that beam passes Earth Jodrell Bank hears a click. So go to this site and listen to the sound of a dead star.

http://www.jodrellbank.manchester.ac.uk/research/pulsar/education/sounds

You may have noticed I haven’t even mentioned Science Fiction. Don’t worry, I get ’round to it.

Happy Halloween

Tomorrow is Samhair, pronounced Sah’-win and better known in our modern world as Halloween. Samhair is one of the quarter points, the days that mark the middle of our seasons of Winter, Spring, Summer and Fall. The days halfway between a solstice and an equinox.

Samhair is the quarter point for the Fall season just as Imbolc, we call it Ground Hog’s day, is the Winter quarter point. There is also the Spring quarter point of Beltane, May Day, and the Summer quarter point of Lughnasa which somehow never got a more modern name.

From what historians and anthropologists can tell, people have celebrated the quarter points just as long as the better know first days of the seasons. The same ancient astronomers who watched the movements of the planets against the background of fixed stars, who saw how the place where the Sun rose in the East every day changed during the course of a year gave us not only the four seasons but the four quarter points as well.

In pre-Christian Europe, the ancient Celtic world (by the way it’s Kel-tic, not Sel-tic) Samhair was the new year, the harvest time and a time when the veil between the world of the living and the world of the spirits was lifted. This was true of all the quarter points, for iron age people they were a time of both fear and promise. Because of the mystical, magical nature of the quarter points the Christian church tried for centuries to wipe out the ancient celebrations related to them. It is a historic fact that one of the heresies that Joan of Arc was accused of was dancing around a May Pole.

In the wider Universe of course, Samhair and Beltane as well as the Solstices’ and equinoxes are special times unique to our planet Earth having no significance on Jupiter or Pluto let alone another star system. It’s only because we are so tied to our home planet and it’s orbit around our Sun that the very idea of a certain day of the year having any significance makes sense. On other worlds Christmas, or your birthday or the anniversary of the Battle of Waterloo have no meaning of any kind.

Nevertheless, as human beings we like to celebrate, to party and the recognition of certain days being special, being a good reason to party gives us pleasure and a chance to connect both with the living and those who celebrated before us. So get out an enjoy your Halloween, have some candy of roast some marshmallows over an open fire and remember how the rhythms of our world are the rhythms of our lives and have been since the beginnings of life on Earth.

Here we go again. The Universe just got ten times bigger!

A team of astronomers led by Christopher Conselice at the University of Nottingham in the UK have been studying the deep field images coming from the Hubble Space Telescope and concluded that the Universe contains ten times as many galaxies as was previously thought.

The previous census performed by the Sloan Digital Sky Survey, SDSS (link below) concluded that the observable Universe contained between 100-200 Billion galaxies.

http://classic.sdss.org/

This new census realized that the density of galaxies in the early Universe was far greater than it is now and that many of these early galaxies were too faint to be seen in the data used by the SDSS. On the basis of their data from the Hubble they have realized that the Universe contains on the order of one Trillion galaxies.

As exciting as this discovery is it’s really nothing new. Every time we study the Universe with new, more powerful, more precise instruments the Universe grows ever larger. Sometimes the expansion is linear as with this census by Dr. Conselice and his team, sometimes it is exponential as when Carl Hubble himself discovered that the smudgy nebula he studied were actual galaxies separate from our Milky Way. By the way, the Greek word galaxy just means Milky Way. From Galileo to Dr. Conselice we have learned that the Universe is more than we can ever imagine.

I have seen this phenomenon of expansion happen three or four times now in my life and I expect to see it happen at least one more time.The James Webb space telescope is expected to be launched sometime in 2018 and with this new window to infinity I have no doubt that the Universe will grow once again.

To read further about the new census follow in link below.

http://www.spacetelescope.org/news/heic1620/

Yes there is a Thirteenth Zodiacal Sign, always has been.

For the past two weeks there have been a number of stories in the news about how NASA is Trying to change Astrology. I’ve been thinking about whether or not to post a blog on this subject and originally decided against it since astrology just isn’t worth talking about! However the story won’t go away so I’ve changed my mind in the hope that maybe this time people will recognize that astrologers don’t even know astrology let alone anything about reality.

For what it’s worth, about 3,000 years ago in Babylon the priests who watched the sky for messages from above (that is how Astronomy got started) decided that the position of the Sun against the background of fixed stars at the moment a person was born must have an effect on that person’s destiny. If the concept of astrological sign means anything that is what it is, the constellation of stars that the sun was in the moment of your birth. Now, I’ll admit that’s an interesting hypothesis, 3,000 years ago it was worth testing. It happens to be wrong but it was worth testing.

Now the ancient Chaldeans, the people of Babylon, recognized that during the course of a year the Sun went through thirteen constellations, that’s right thirteen, the twelve zodiacal signs we’re familiar with plus the constellation Ophiuchus. By the way, this is why a very easy to spot constellation like Orion or the Big Dipper is not a zodiacal sign while a very difficult to find constellation like Capricorn is.

The trouble started immediately. The Chaldeans didn’t like the number thirteen, it was considered unlucky even back then. So they just threw out the constellation of Ophiuchus, reality after all has to match our irrational prejudices. There was also the problem that some of the constellations of the zodiac are bigger that the others so the Sun spent more time in some than in others. The Babylonians solved this problem by just each making each sign the same length of time whether it should be or not. This then gave us the signs of the zodiac we’re all familiar with, Aquarius 20Jan-18Feb, Pisces Feb20-Mar19 etc.

But there was another problem the Babylonians didn’t know about, the precession of the equinox, the precession of the Earth’s axis in a huge circle every 26,000 years. The fact that it takes so long is the reason the Babylonians didn’t know about it. However it does mean that about every 2200 years the entire zodiac gets shifted by one entire sign to the left. It’s the dawning of the age of Aquarius remember, well that’s because for the past two millennia the equinox has occurred while the Sun was in Pisces but soon it will occur in Aquarius because the entire zodiac has shifted by almost one entire sign.

Now astrologers have either ignored of been ignorant of this plain fact for, well since the beginning of astrology. Because of this ignorance of their own “science” they have basically given almost everyone the wrong sign. For example, I was born on the 4th of September, which makes me a Virgo. Except that the Sun happened to be in Leo the moment I was born so, if astrology means anything at all I should be a Leo.

None of this is news. Astronomers have made headlines by pointing out the truth four or five times in my Life and the fact that reality is so quickly forgotten again is, disappointing at the very least. NASA has even had to publically say they aren’t trying to change people’s sign, actually they have issued a statement that astrology isn’t science anyway so it doesn’t matter.

As I said, we have gone through this several times in my life so at the very least it would be nice it would be nice if astrologers would take a little time to learn astrology. I’m not holding my breath.