Sunday, January 30, 2011

A Little Fun With Your New Astrological Sign

Now I know you are a little distraught over the fact you are not what you think you are when it comes to astrological signs so I have decided to set up a one time therapy session dealing with this oh so important revelation to the astrological believing public. When I got wind of this upheaval in the whole  astrological community I was shocked because all you really had to do was look at a star map and then with a few calculations figure out... Hey the Sun is not where it should be. He is visiting next door in some other signs house. Psst(whispering)  astronomers have known this for a looong time. We should have said something many hundreds of years ago and we didn't and for that the scientific community surely apologizes. What the heck happened? I was born  Wednesday on June the 8th so that would make me a Gemini well up until a few weeks ago that is. 

There were a couple of problems  for ancient astrologers  when they set up this zodiacal system. There were 13 constellations in the ecliptic...  always was.  Astrologers may have thought 12 sounded way more cooler than 13  so they decided one of these signs has got to go. I guess they thought long and hard about it  and finally tossed Ophiuchus out. So why him ? Here is my guess. Would you want your daughter to be called a snake handler? or boy for that matter? Way too much teasing going on... They knew kids were ruthless!  So that is why Ophi got the pink slip. They had their 12 houses (kind of) and all was happy except... They did not count on precession. The Sun and Earth do a dance constantly of wobbling in rotation and in orbit. Gravity is a constant relentless action between objects. the two main precession problems are axial and ecliptic precession

Axial precession is the movement of the rotational axis of an astronomical body, whereby the axis slowly traces out a cone. In the case of the Earth, this type of precession is also known as the precession of the equinoxes or precession of the equator. The Earth goes through one such complete precessional cycle in a period of approximately 26,000 years, during which the positions of stars as measured in the equatorial coordinate system will slowly change; the change is actually due to the change of the coordinates. Over this cycle the Earth's north axial pole moves from where it is now, within 1° of Polaris, in a circle around the ecliptic pole, with an angular radius of about 23.5 degrees (or approximately 23 degrees 27 arc-minutes). The shift is 1 degree in 72 years, where the angle is taken from the observer, not from the center of the circle.

Aristarchus of Samos (c. 280 BC) is the earliest known astronomer to recognize and assess the precession of the equinoxes at almost 1º per century (which is not far from the actual value for antiquity, 1.38º).The Precession (axial rotation) was later explained by Newtonian physics . Being an oblate spheroid, the Earth has a nonspherical shape, bulging outward at the equator. The gravitational tidal forces of the Moon Sun apply torque as they attempt to pull the equatorial bulge into the plane of the ecliptic. The portion of the precession due to the combined action of the Sun and the Moon is called lunisolar precession.  Astronomers knew way back then  you could not put an immovable system into a constantly moving system and not have  some problems. I guess the did not get the memo to fix their problem 2200 years ago or so another precession is ecliptical
The inclination of Earth's orbit drifts up and down. Relative to its present orbit this drift has a period of about 70,000 years. Relative to the invariable plane it has a 100,000 year period. The invariable plane represents the angular momentum of the solar system, and is approximately the orbital plane of Jupiter. To the observer the Sun now is moving through  some astrological houses for just two weeks and some for as long as three months! This concrete unmoving system is  having a tough time of it in the modern world.

So what will be the outcome? well I believe there will be two camps, one of which my darling daughter Meghan is camped out in and then the one I am finding a home in . My dear sweet Daughter was born in early September and that makes her a Virgo in her mind ... So much so that she decided to have a tattoo of Virgo stamped near her bikini line. When I told her she was not a Virgo  but a Leo she leaps at me like a lion Hmmm. Meg roared she does not care what house the sun is in she is a Virgo! I even offered to have a red X tattooed through her Virgo tattoo. She just growled at me.... Hmmm.

As for me  I started to reflect upon this transition. I was a Gemini and now I am a Taurus and then it hit me like a ton of bricks. Oh my stars I am  and have always been a Taurus . I remembered when my dad would ask me where I had been. I would tell him  and he would say that sounded like a load of Bull. or even later in life when I was giving a presentation of why we need to expand our  efforts to look for the Ether I was met by  a score of people  chanting ...Bull! OR right about now when you read this and cry Bull Hockey! Yes I am feeling quite comfortable in my new Bull digs. I think my sweet wife has known for awhile that I was  full of Bull .
Until next time,

Keep looking up!


Saturday, January 29, 2011

The Carnival Is Back In Town

 The Carnival of Space is back in town. Everything from space to spaceships are there and everything in between. All kinds of fascinating stuff await your perusal. The host this week is Brian Wang of Next Big Future. This is a spot to stretch your mind as you try to get your head around the next big thing in science Take a moment and check out some of the Blogs there. I have always loved a good carnival  You will love this one! Ready set GO! Here

Sunday, January 23, 2011

It Is Never a Dull Moment With Cataclysmic Variables

I am in the middle of getting a presentation together for Cataclysmic Variables (CV) and thought you might like a crash course in it as well. Cataclysmic variables are binary systems that consist of an normal star and a white dwarf. They are typically small. The  typical binary system is roughly the size of the Earth-Moon system - with an orbital period in the range 1-10 hrs. The companion star, a more or less normal star like our Sun, loses material onto the white dwarf by accretion. This part is kind of interesting so I will give you some background on the setup. The white dwarf  was at one time a regular schlep of a star. For few billion years or so it cooked hydrogen into helium by fusion. Sadly the star eventually ran out of hydrogen so what do you do? you start fusing helium together until you wind up with a mostly carbon rich star that has ceased fusion and is just hanging out cooling down for the next billion years. While all of this was happening the star went through the red giant phase etc. So there it sits a sun like mass squished down into the size of the earth.This makes for a very dense and more to the point, a huge gravity well. Ah but what if there was a close by companion star? A regular star in most ways except for the fact that it is in an orbit with the earlier mentioned white dwarf? This scenario has the makings for a CV

There are several types of CVs out there and all of them have different ways of doing their business. Let's break CVs down into some bite sized chunks. For starters there are two major types of CVs. One has a fusion dominated  phase. The second has an accretion disk dominated phase.

Fusion Dominated  includes 
1.Classical Novae
2.Super Soft Sources (SSS)

 Classical Novae
A classical nova occurs when material (drawn from the companion star) accretes onto the surface of a white dwarf star's surface and thus begins an unstable thermonuclear fusion reaction. Material transfer will gradually occur between novae explosions  The mass will be accreted onto the white dwarf's surface at a low rate, generating only weak X-ray emission. The nova outburst will increase the apparent brightness of the binary star system by ten thousand to a million times (an increase in stellar magnitude of 10 to 15). Can I get a Wow! there? The reason is  fairly simple  in that the slow build up of material causes the bottom layer to compress and finally is set off on the fusion path. At this point all of the material is fused at the same moment releasing a massive explosion of light /energy  They are thought to recur, though with recurrence time scales of 10,000 years, We will just have to wait and see if it happens again. No known  classical novae recurrence have been observed.

Super Soft Sources
Super Soft Sources (or SSSs) are the new kids on the block in the family of cataclysmic variables. This CV was first categorized by ROSAT observations.  SSSs are objects with temperatures of between 200,000 and 800,000 K and luminosities around 1038 ergs/s. More than 90% of their observed X-ray emission is below 0.5 keV. The leading theory is  SSSs are white dwarfs with classic hydrogen fusion occurring from material accreting onto their surfaces. This could make SSSs the progenitor for Type Ia supernovae.
In the white dwarf scenario, the observed black body radii is simply the size of the white dwarf star itself with nuclear fusion occurring on its surface. If accretion occurs onto the white dwarf surface at low rates, fusion will be sporadic and violent, just like classical novae type explosions. If accretion is at a high rate, the white dwarf will acquire a red-giant-like atmosphere. Continuous nuclear fusion on the dwarf star surface would be possible only for a narrow range of accretion rates of the order of 10-7 solar masses per year. For relatively massive white dwarfs 0.7 - 1.2 solar masses, this raises the distinct possibility that such objects could eventually exceed the Chandrasekhar limit,  making them the candidates for Type Ia supernovae. White dwarfs have a limit to how big they can be  If they get larger than 1.4 solar masses they will inevitably supernova and collapse into a neutron star. That is what the Chandrasekhar limit is. That takes care of  the fusion dominated side of CV's. Now let's take a look at accretion dominated CVs.

Accretion dominated CVs can be chopped up into three main categories. all of which are fascinating in their workings. They are:

1.Dwarf Novae
3.Intermediate Polars

Dwarf Novae

Dwarf novae (DN) outbursts are dimmer events than classical novae outbursts. Their peak absolute magnitudes are weaker by at least 100 times. DN  are known to recur with times as short as a few weeks. DN also have short durations, lasting just a few days. Interestingly, dwarf novae also can exhibit a variety of unusual behaviors. Some occasionally exhibit long outbursts known as superoutbursts


In a polar system  matter will overflow the Roche lobe of the companion star. However, the white dwarf possesses a strong magnetic field, which prevents the formation of a accretion disk. Instead, the overflowing material is directed by the magnetic field structure until it impacts on the surface of the white dwarf at its magnetic pole. Until impact, the material essentially free falls, thus reaching substantial velocities which are seen in the optical spectra. The collision generates a shock wave which is the source of hard (energetic) X-rays. Hard X-rays emitted in the direction of the white dwarf from the shock wave heat the local area around the pole enough for the pole to become a source of intense soft (less energetic) X-rays.  Polars are generally much stronger sources of soft X-rays than hard X-rays. This is probably due to uneven matter streaming. knots in the accretion flows would most likely cause energy to also be let go deep within the atmosphere of the white dwarf. This results in more soft X-ray emission. The strong magnetic field will also tidally lock the orientation of the white dwarf relative to the companion, so that orbital and rotational periods are identical.
X-ray emission from polar systems is entirely due to the accretion column and its impact, so in quiescent times when matter is not accreting onto the system, the entire system is much dimmer.

Intermediate Polars

When a Polar has a wide separation between companions or does not have an outstanding magnetic field  but still a very good one  an accretion disk can and will form. When this action is found  The moniker of Intermediate Polar is bestowed on the pair As material migrates inwards in the disk, it may eventually encounter a magnetic field strong enough to control the flow of material, at which point matter would instead stream from the inner edge of the disk along magnetic field lines onto the pole of the white dwarf. Such a system would therefore be expected to be a source of hard X-rays from the shock at the magnetic poles. Intermediate polars, either due to weaker magnetic fields or wider star separations, will not necessarily have orbital and spin rates locked. Observed systems have longer orbital periods than polars, which given that the systems have comparable masses verifies their wider separation.

Now if that wet your whistle for the wild world of variable stars then hop on over to the American Association of Variable Star Observers here and get a handle on variable stars  You could even discover one! They happen all the time

Until next time
Keep looking up!

Steve T

Monday, January 17, 2011

A Glorious and Cold Night Camping with The Scouts

Troop 128 out of Milford Ohio made plans to backpack down a very scenic trail in  John Bryon State Park. It was a cold crisp day and all was right with the world. The morning brought overcast skies and snow showers but to a Boyscout this was just icing on the cake for a grand day in the great outdoors.. Earlier in the month the troop had contacted the Cincinnati Astronomical Society to set up an observing session at their campsite. Now if you know anything about Midwest weather  the word of the winter season in the Midwest is clouds. We do get (once in a blue moon) some nice crisp night with the winter sky blazing in all of it's glory. I said by all means we will have a program for those boys. My general rule when dealing with weather and scouts is to have a plan B in the ready. Plan A of course was the bringing out of telescopes to find and pierce a sucker hole looking for a wonder lying within the hole. For this I had two other Volunteers,  telescopes at the ready. We  had 20 boys on this particular Camp-out to take care of. With three scopes it was going to be a piece of cake...  Right?

Not exactly... The clouds were relentless  and we ended up going to plan B. In my mind There is nothing more fun than sitting around a campfire telling stories and having fun. So why not mix those two events? I had twenty boys sitting there listening to me regale about Galileo and how he took astronomy into the modern age with the telescope. The Boys were all too eager to ask questions and I fielded them all. everything from the 2012 end of the world scenario that will not happen to how we got our water on earth. It was a fun night and a memorable one for the boys. That was the pinnacle of fun for the weekend. Friday The CAS kicked off it's celebration of one hundred years in the astronomy gameand I was there to share in that oh and on Thursday I gave a presentation at the Cincinnati Observatory Center on asteroids and was able to share a peek at the moon with our visitors for a very brief moment though a sucker hole in the sky. The telescope we used was the 1842 Merz-Mahler 12 inch refractor.This is one of the oldest telescope you will ever look through. So what did you do this weekend?  Get out and share the beauty that is the night sky with others You do not need a fancy  telescope or a clear sky.  Just share a little bit about what you have seen and say to them: Get  thee to a telescope as soon as you can!

Until next week,

Keep looking up!
Steve T

Sunday, January 9, 2011

The Cincinnati Astronomical Society is 100 Years Old!

The city of Cincinnati Ohio is ever so fortunate to have two astronomy centers  that have stood the test of time and are 100 years or older; the Cincinnati Observatory Center (168 years old) and the Cincinnati Astronomical Society  100 years old this year. Both of these fine organizations share many of the same goals in education and public out reach but one hundred years ago it was not like that.

The Cincinnati Astronomical Society (CAS), established officially in 1911, traces its origin to probably 1909. One of America's earliest established amateur astronomical societies; it experienced two unique periods during its history. The first period, 1911 to 1941, was dominated by Dr. Delisle Setwart, the Society's founder and President, as he attempted to establish a quasi-professional observatory. The second period, 1941 to the present, was administered by 14 presidents as they guided the Society in its pursuit of classical amateur activities -- telescope making, learning astronomy, and public educational activities.

1911 - 1941

From 1896 to 1910, Dr. Delisle Stewart served as an assistant astronomer at the Cincinnati Observatory of the University of Cincinnati. Research at the observatory during this period centered on the classical stellar measurement techniques. Stewart attempted to persuade the observatory's director to apply the then new astronomical research tool, astrophotography. Stewart's interest in astrophotography was intensified by his Harvard training and his previous two years service at Arequipa Observatory, Peru, where he photographed the southern skies. Stewart eventually lost his job over his persistent attempt to persuade the Cincinnati Observatory to adopt astrophotography.

Stewart's response to his rebuke was to establish a new astronomical society with the goal of building a new observatory dedicated to astrophotographic research. The Society's name, Cincinnati Astronomical Society, was borrowed from the original CAS, 1845-1870. This was the first professional astronomical society in America. Its telescope and assets were donated in 1870 to the city of Cincinnati. The city subsequently donation the assets to the University of Cincinnati (and its then new Cincinnati Observatory) from whence Stewart was dismissed.

An unusual event occurred in Cincinnati in 1911 that affected, initially positively but eventually negatively. Stewart's plan to establish a new observatory. The city was rightfully proud of its Chamber of Commerce building that was designed by the famed architect Henry Hobson Richardson. The building received world-wide recognition for its beautifully carved, expansive, Romanesque arches. The edifice was destroyed by fire in 1911. Since Stewart was a lover of Richardson's work and the city loved its Chamber of Commerce Building, Stewart found a way to turn this disaster to his advantage. He offered to build his new observatory based on the architectural plan of the Chamber of Commerce building. The new observatory would then be faced with the Richardson granite stones that were salvaged from the destroyed building.

The citizens responded to Stewart's concept by generously donating services to transfer the huge Richardson stones to a temporary storage site and by buying bonds that were issued by CAS. Sufficient funds were acquired within three years of the fire that CAS acquired 142 acres of land in Miami Heights/Mt. Zion (the current CAS location) for the new observatory site about twenty miles west of Cincinnati. The site's principal selection criterion was its distance from the city's light pollution, a problem that then prevented the inner-city located Cincinnati Observatory from performing adequate astrophotography.

All of the solicited funds were consumed in financing the transfer of thousands of tons of the massive Richardson stones from the original downtown site, to their temporary storage site, and finally to Miami Heights/Mt. Zion. The largest stone weighed 27,500 pounds. For the next twenty years Delisle Stewart begged wealthy Cincinnatians to purchase the remaining CAS bonds in order to raise the required funds. Finally, by the end of the 1930's, sufficient funds were obtained so that the observatory's construction could begin.

The architects designed a two-story observatory building that included a large central dome and two side domes--each mounted on the end walls. The building's main floor was designed to include offices, a reception hall and museum of astronomy, a lecture hall, classrooms and the Richardson Memorial Collection. The second floor was to have a library, reading and study rooms photographic darkrooms with separate rooms for plate storage, spectroscopic and photometric laboratories, and rest rooms for the night observers. The domes were to house two large reflecting telescopes and one large refractor telescope. As with icing on a cake, the observatory would be faced with the famous Richardson granites. Assuredly this would be a magnificent facility, one in which the Cincinnati Astronomical Society and the city would be proud.

The effect of the Great Depression took its toll on CAS and its observatory. Construction of the basic outline of the building was completed, and the basement was finished to a degree that the CAS members could use the area for a meeting room. However, the Society lacked the funds to complete the project.

1941 - Present

With the death of Dr. Stewart in 1941, the Society lost its driving force. There was no one left with the ability of desire to make another effort to raise the required funds, and somehow, to complete the building. It was ironic that the Richardson arches, which had inspired the construction concept, proved to be its undoing; not a single block of granite was raised into place. The granite stones remained strewn around the observatory site, mockingly tombstone like.

For the first 32 years of its history, CAS was dominated by Dr. Delisle Stewart. Since 1941, the Society underwent a transformation from a quasi-professional society to an amateur one. From a society on the verge of extinction, it had rebounded to become a responsive, respected organization under the direction of fourteen succeeding Presidents.

Those interested in reading the complete history of the Cincinnati Astronomical Society are invited to read the 132 page book A Brief History of the Cincinnati Astronomical Society , by John E. Ventre and 
Edward J. Goodman. (History  borrowed from CAS website)
Now did that whet your appetite? If it did then by all means you need to mark your calendar for January 14th @8:00PM  The CAS is kicking off it's celebration of 100 years with the History of the Cincinnati Astronomical Society  and a look at the next hundred years plus a public star gaze held at the headquarters grounds located on Zion Road across from the Mitchel Memorial Forest. You will be able to take a look through one of our wonderful scopes  and get a glimpse of what has made the CAS a lasting  force in amateur astronomy! 
Until next time,
Keep looking up!

Steve T

Sunday, January 2, 2011

The Death Of a Star Can Bring Life

Supernovae  have the ability to build the elements for life  and disperse them through out their region of space. New star formations use these heavy elements and organic compounds to form the planets within its accretion disk.This action from ancient explosions of stars  provided most of the elements needed to kick start life on a planet.
When the largest of  stars exhaust their hydrogen fuel, they start producing energy with nuclear reactions that fuse helium into carbon. When they exhaust their helium, they fuse ever heavier elements in their cores until they have iron cores. Iron is the boundary between nuclear fission and fusion reactions, so no additional nuclear reactions will occur in the core. Gravity takes over  and Boom! we have ignition
This release of energy is enough to fuse elements on the periodic table heavier than iron and blast them into space to be recycled into the next generation of stars and planets. Supernovas are the source that create the elements  needed for life on Earth. 

 A property of Earth's organic molecules could be caused by supernova, suggesting that life’s building blocks were created somewhere other than earth. Many of these building blocks, such as amino acids, sugars and other organic molecules, are chiral. Meaning: they come in two identical forms that are mirror opposites.  They are asymmetrical mirror images of each other, so you cannot superimpose them on each other. They are considered right- or left-handed depending on how their atoms are arranged. On Earth, life likes to be left-handed . Left-handedness also seems to prevail throughout the cosmos, according to studies of meteorites. Researchers from the Lawrence Livermore National Laboratory believe supernovas are the reason.
When a star collapses, it ejects all kinds of particles including electron antineutrinos, which are right-handed. Nuclear astrophysicist like Richard Boyd and his colleagues suggest these particles would interact with right-handed nitrogen atoms inside amino acid molecules.
This interaction would convert the nitrogen into carbon, thereby destroying the righty amino acid molecules. The left-handed nitrogen would be left alone mostly which means left-handed amino acids would be dominant. That could explain their abundance on Earth and elsewhere in the universe.

 Other evidence that points to life  building block can be found by the recent Spitzer and Chandra Space telescope discoveries of PAHs (polycyclic aromatic hydrocarbons) being found in Supernovae seem to survive the supernova explosion. These carbon and hydrogen compounds are found in comets, in star-forming regions and planetary disks, which also seem to be where supernovae are found. 

 That should be enough to chew on for awhile.  

Until next time ,
Keep looking up!
Steve T

Ushering in a New Year!

2011  is a new year and a celebration of all things astronomy. This year marks the 100th anniversary of the Cincinnati Astronomical Society. I am proud to be a part of this wonderful milestone. The CAS has long been a friend to the community with its outreach programs and participation with other astronomical and science groups from across the Ohio Kentucky and Indiana region. This year I will be blogging regularly on astronomical topics as well as events for this important celebration so look for a new post soon like later today!  

Keep looking up!
Steve T