NEW YEAR-------NEW THRILLS

LASS hosted the first observing party of 2012 last Saturday night and it was a booming success.  Six regulars and two guest spent the early evening hours looking at Jupiter, Venus, and Orion as well as a host of other nice targets.  The Goat Hill Clear Clock site that is nearby indicated that we would have good viewing until about 9 PM and as usual, they were accurate almost to the scary point.  Early evening viewing was outstanding so all of us took full advantage of the opportunity.


I had checked the Heavens Above web page for chances to see any of the major satellites and Iridium flares---nothing was going to be available along those lines so I looked at my planetarium program for unusual things that we might want to observe.  I didn't see anything special so we just planned on doing the usual Messier things  and visiting.  After all, visiting is a very major part of the LASS program.  Early in the session most of us took a quick look at Jupiter and noticed that only one moon was actually visible.  We talked about this for a little while and then went about the task of looking for something else.  What we didn't realize was something special was taking place around Jupiter and we weren't even aware of it.  At least we hadn't checked it out and we didn't  know what was actually going on around the big planet.  All of this emphasizes the importance of having a thorough observing plan for every time you go out to look.


Less than an hour into the session someone checked on Jupiter again and made the discovery that one of the moons was just making its appearance from behind/in front of the big red giant.  We all gave it a quick look and within a couple of minutes a second moon appeared on the opposite site of the disk.  Suddenly we realized that we were seeing something very rare and we began to pay a lot of attention to the proceedings.  Within a very short time the fourth moon appeared but it wasn't from behind Jupiter but it appeared almost without warning at a distance from the planet.  To sum it up, we went from one moon visible to all four moons visible within a very short time.   I noted the time that all this was taking place and the next day consulted my trusty planetarium program for an explanation.  Here is what I found.


When we began the observing session shortly after sunset, but before full darkness, we were observing Jupiter with its moon Callisto in all their beauty.  Europa was already transiting the face of the planet but since we weren't aware of that we didn't look for it.   At 6:29, Ganymede emerged from behind Jupiter and we were lucky enough to be looking at almost the exact time that event occurred.  Then at 6:42, Europa completed its transit of the planet and showed itself on the opposite side of Jupiter from Ganymede.  It was almost impossible to tell that both moons were not touching the outer rim of Jupiter at the exact same time.  From 6:15 to 6:42 we went from only one moon visible to three visible.  Then something else happened that we didn't know until the next day when I checked the planetarium program.  At 6:55 shadow of Europa began a transit across the face of Jupiter.  I will admit that it is very hard to follow one of the moons as it transits the face of the planet but the shadow is fairly easy to detect and follow---that is if you know it is going to cross.  By now some of us were getting curious as to the location of the fourth moon and when it might emerge from behind Jupiter.  At 7:51 we had our answer but it wasn't exactly what we were thinking.  It appeared very quickly as the outer most moon---not even anywhere near the edge of Jupiter.  It had not been behind the planet at all but was being eclipsed by Jupiter's shadow.  Then as a final event for Jupiter's evening, the shadow of Europa fell off the edge of Jupiter at 9:13 PM.  Quite a lot of moon activity for one evening.


What is the moral of this narration you might ask?  SIMPLY THIS---if I had looked at the planetarium program in detail I could have been aware that all this Jupiter activity was going to happen.  We did see very part except the shadow of Europa but it was by accident only---nothing that we had planned.  It was neat to see the events unfold as they happened but it would have been a little more exciting for me if I had been aware of how they were going to appear in my scope.  And I always get a special thrill when I watch one of the moon shadows cross the face of Jupiter.  We missed that opportunity by not checking and planning.  I hope to do better in the future.


Incidentally, we did see some great views of Venus and Orion.  Our guest seemed to have a good time and thought they would be coming back again.  But just on schedule according to the Goat Hill Clear Clock prediction, the clouds began to move in shortly after 9 and that ended our first observing session for 2012.  I am looking forward to many more this year.  Hope you can join us for some of them.

EARLY MORNING NIGHT THINGS

Truthfully, I am not what you would describe as a night owl.  Oh I will get up at 3-4 AM to look at a meteor shower or some other once in a night time event but generally speaking if it doesn't happen before midnight it isn't on my radar.  Our annual Messier Marathon is another exception but that accounts for most of my late night astro adventures.  I have been known to attend an extended star party but even then I seldom make it up all night. But I do appreciate what that early morning look has to offer.


The last few mornings I have been up around 4 AM to check on the temperature in my greenhouse.  I always turn the heat on before I go to bed if the weather forecast is below 40 degrees for the night.  The reason I choose 40 degrees is my mistrust of the weather forecasters. They generally are within 5 degrees of the low but if it gets below freezing in the greenhouse, I am in deep trouble.  So I get up and check just to make sure.  It is well worth the effort.


Right now, my night time routine is as follows----around 8 PM I make it out to the greenhouse to turn on the heat if it seems that it will be needed anytime during the night.  Venus is so brilliant at that hour that I am sure someone with good eyes could read a book without any other light source. The moon hasn't made it up yet so that makes Venus seem even brighter.  In fact, Venus is bright enough to have the same effect as a bright moon.  A lot of the dimmer stars are simply washed out.  But I glance around and see what there is to see and then make it back inside to watch the late news and get ready for bed.  Then around 4 AM I pull on my sweats and trek out to check on the temperature.  That's when I really get an eye full of the morning sky.  Lately it has seen severe clear at that time of the morning and for some unknown reason ( although I know it is just my imagination) it seems like there is less light pollution.  The moon is up by that time and shinning brightly but if I stand in the shadow of the clubhouse the stars just jump out in the clear, crisp sky.  The amazing thing is the orientation of the stars and constellations.  It has been so long since I have seen them at this time I needed to get my star and planet locator out and get myself orientated. I know that doesn't sound like a guy who really likes to look at the night sky but it is the truth.  Even though it has been rather cool these last few mornings, it is easy to forget that and simply concentrate on what I could see.  Not so much that I wanted to drag out the old 20 inch Dob at that hour but it does get the juices circulating.  I have resorted to taking out the 10X50's binos to look at a few things.  I haven't had the bino chair out lately but it seems like this might be a good time to get it ready for use. There is one simple thing that I can't seem to understand about all this---when it gets to be that night for the monthly LASS observing session, the clouds seem to move in, the wind starts to blow and the temperature falls out the bottom of the gage.  WHY, WHY,WHY.


Speaking of monthly star parties, January 21st is the date for our 1st gathering of 2012.  I want this year to be a more productive time for our club and I encourage all local members to make every effort to come out.  Getting together seems to be a shot in the arm for me. It makes me want to find things that I haven't seen in a long time and at the same time I find myself wanting to visit with the other club members to see how their observing sessions have been going.  This first meeting after christmas is also a good time to find out what others may have found under the astronomy section of their christmas tree.  SEE YOU THE 21st.


    











   

WHAT IS GOING ON OUT THERE?

This rant may be just a little far out for a local astronomy blog but I found the subject very interesting so here it is.


       THE AMAZING KEPLER TELESCOPE


Some time ago I wrote an article about the "Kepler" space telescope and what might be found by that fantastic piece of equipment.  (See post  "How Many Solar Systems Are Out There", January 2010.)  Well, it is about time to do an update. At the time I posted that article there was approximately 400 stars in our galaxy that had known "exoplanets".  A exoplanet is a planet circling its star in the same way that earth and its friends are orbiting our sun.  Since then the number has swelled to over 700 known stars with exoplanets and there are thousands of star candidates that are waiting in the wings to have their own solar systems confirmed by astrophysicists who are studying the available data.  In terms of astronomy discoveries and advancements, that is an astounding change in our understanding of our universe.   As little as 40 years ago no one knew that there was any other star with a solar system that even resembled ours.  Not that any of these new systems are anywhere like ours in their overall makeup but just the fact that we have made these discoveries is amazing.  


In terms of how large space really is, think of this.  There are roughly 100 billion stars in the Milky Way galaxy.  If only one in four had four exoplanets that would be 400 billion pieces of something floating around in the space of our Milky Way galaxy. Now that doesn't even count all the asteroids and man made objects that are in our own private solar system.  If you really want to get imaginative, think about the fact that there are billions of galaxies out there in the known universe with billions stars in each one and the possibility of exoplanets around all those stars----my goodness we are approaching a number as large as the national debt. 


Now before you start salivating about all these things that you can see I need to bring you down to earth---so to speak.  No back yard astronomer has even come close to seeing an exoplanet in our Milky Way galaxy much less something that small in a distant galaxy.  We can't even break out stars in galaxies other than our own.  But the big guys with the fantastic scopes like Kepler and other measuring devices have be able to detect these objects.  Now hold on to your pants!!! There are even pictures of these rascals. You read correctly---there are pictures of these exoplanets and even pictures of stars that have more than one exoplanet in orbit around them. 
   This is one of the very first pictures showing at least two exoplanets orbiting a star simply identified as HR 8799.  This star is roughly 5 times as bright as our sun and lies 130 light years from earth.  This image was acquired in late 2008 and since then there have been other exoplanets imaged. (double click the image for a larger view)  They are out there folks but the sad thing is that even the nearest ones are so far away that there isn't even a remote (at least creditable) theory as to how we might reach them with anything except cameras.  It is kinda like a kid in a candy store standing in front of the counter and seeing all that candy and knowing that there is no way any of it is going to get into his mouth---then some generous benefactor comes by and puts down 25 cents just to see the kid grin.  Unless some scientific benefactor suddenly comes up with something that hasn't even been thought of,  I don't see any space travel outside our small solar system in my lifetime or even the lifetime of my great grandkids.  But it is so amazing to know that we humans can learn so much about the universe around us.  We may not be able to travel there or to make contact with any other living organism that may exist out there but at least we know that we are very special in all that expanse.  I can well remember about 70 years ago when me and my dad would be outside looking at the night sky and I would ask if it would be possible for anyone to go to the moon.  His simple response was, "it is not intended for mankind to go to the moon."  Well, maybe it was not intended, but someone forgot to tell those who had the foresight to imagine.  I'm glad we have folks around us that have that imaginative spirit.

HOW TO AVOID BUYING THE WRONG TELESCOPE

There are a lot of folks out there that want to buy a home so they can start living the GREAT AMERICAN DREAM.  That was one of the first things that Lucy and I did when I finished all the Air Force flying schools and we arrived at our first permanent assignment.  It was a modest little home---900 sq ft with an attached garage.  Plenty of room for a young couple.  Plenty big enough to have company or start a family.  It served us very well for four years then we were reassigned to England and we sold the house and all the furniture we had acquired.  I won't say that we did a lot of extensive research before we bought the house but we did considered the convenience to the base where I worked,  the overall appearance of the neighborhood,  the total cost, and the possible resale potential.  Looking back some 56 years, we think we did pretty good.  We didn't make a lot of money on the resale but the experience we gained throughout the process paid dividends in home purchases we  would make in the future. 


When I finally discovered my interest in astronomy observing I knew immediately that I wanted a telescope of my own.  The possible selections of what to buy were almost endless.  Since it was an entirely new hobby to me I wanted to make sure I would stay with it long enough to justify the expense of a telescope and that whatever scope I chose would be something I could and would use.  But in reality, you don't know initially if you will develop a longtime interest in the hobby.  That puts you in a slight delima at first but in my case there was a viable solution.  That solution is what I want to discuss in this article about how to avoid buying the wrong telescope.


The telescope that I was looking thru when I really got "hooked" was a 20 inch DOB that a professional observer from the Mcdonald Observatory at Ft Davis, Tx was using to teach a two night astronomy session to a bunch of folks who were on a activity planned vacation. For those of you that don't know much about scopes, that's a "REALLY BIG ONE".  You had to climb up a ladder to look into the eyepiece and the instructor had to continually keep adjusting the scope to keep the desired targets centered.  No matter what the difficulty was, the view of the Andromeda galaxy thru that eyepiece was simply mind boggling to me.  I knew right then that I wanted a telescope.  At the time a scope like that would cost somewhere in the vicinity of $2500/$4000 dollars.  A whole lot more than any beginner should even consider investing in a hobby that might or might not be a long lasting one.  I needed an avenue to find a scope that I could use that would be both economical and functional. For me that avenue was to begin reading articles in Sky & Telescope magazine and join a local astronomy club.  It was a full 1 1/2 years before I made the decision to actually buy a telescope.  Not that I had wavered any in my desire to own a scope but for me I wanted it to be one that I could use and actually see the objects of interest in the sky.

The first scope that got my eye was a Meade 4 inch computerized telescope that  you could use on a tripod or sit on the top of a table. It was small, easily transported and that computerized mount sure looked inviting to me.  I wouldn't have to know very much about the night sky to be able to see things using that baby.  At least that is what I had in mind.  I must have looked at that scope in a dozen or more telescope shops over the course of that 1 1/2 years. It could be purchased for somewhere around $400 dollars.  A 4 inch mirror is a fairly small mirror for a reflector scope and I knew that the larger a telescope mirror was  (basically the size of the telescope) the more light it could gather, hence the more potential there was to see more things. I wanted a scope with the largest mirror I could afford to buy. Finally, I set a top price that I felt that I could spend and that opened several more options to me and closed other options.  Any type of computerized scope larger than the 4 inch model would be well beyond my dollar allowance so that pretty much ruled out a computerized scope for me.  Additionally by this time I had come to realize that for me learning the night sky and how to find objects by manually searching for them (of course aided by charts etc) was a part of the hobby that I wanted to develop.  So it was back to the catalogs to find a scope that would meet all those requirements.

 I settled on an 8 inch reflector that was on an equatorial mount.  I must confess here that my memory does not tell me why I decided on the equatorial mount other than to note that once properly aligned and the target located you can track the target with the simple rotation of a guidance knob on the mount.  There are a few other details to observing with an equatorial mount but I won't go into those here.  In April 2000 I set down in front of my computer and ordered a Orion 8 inch scope.  It cost me about $200 dollars more that the 4 inch would have and about $300 more than a small DOB I was considering. That 8 inch scope served me well for a couple of years and I still have it.  However, after a couple of years of observing I decided that a DOB type scope would be more suited to my observing habits. All astro observers fall prey to the "larger scope" syndrome sooner or later and I was no exception.  I also discovered that the hobby of star gazing was really something I liked to do so I was willing to spend more money to satisfy myself.  It wasn't long until I plunked down about $800 dollars and became the proud owner of a Meade 12.5 inch Dobson scope.


That bigger and better scope for me was still a reflector scope but it was on a Dobson mount.  Most often these scopes are simply referred to as "DOBs".  For simplicity purposes, think of a DOB as a tube that sits on a lazy susan so you can push and pull it where ever you want to point it with almost no effort.  Generally speaking, a DOB with a solid tube to house the mirror is just that---a tube and a base mount.  Two pieces and that is it.  Because of the simplicity of the design, the scope is much less expensive than any comparable sized scope with a different type mount.  It is by far the easiest scope to use because you simply push or pull it toward the desired target.  However, you must constantly make small adjustments to the scope because it doesn't track the desired objects automatically.   Don't be misled here---with any non computerized mount,  regardless of type,  you are going to have to know the sky above you if you are ever going to find things to look at.


With all the simplicity of the DOB, there are things that you must consider.  Weight and the length of the tube assembly are the major factors.  A solid tube 16 inch DOB can easily weigh up to 100 lbs and the base can weigh about 75 lbs. The tube can be 6 feet or longer.  Lugging that kind of weight around on an observing site can be a little intimidating.  But where there is a will there will always be a way and this is no exception. 

Someone with a great vision simply sawed the mirror box off the bottom of the tube, added some lightweight truss bars and put the top cage on the other end and you now have a 3 piece DOB that can be easily disassembled and moved.  The limiting weight factor became a mute point and DOBs really got big.  Most of these big babies were hand crafted until a couple of years ago when scope manufacturers got their act together and began to mass produce the "truss Dob".


By this time, (about 2008) I was really into the observing thing and the desire for a larger, truss type began to enter my mind. A friend of mine happened to have a 15 incher and offered to trade it to me for my 12.5 incher and a few $$$$ to boot.  It was a deal I simply couldn't refuse.  That scope was just what the Dr. ordered and it seemed perfect for me.  Not to big to move around but big enough to really see and observe deep sky objects.  Then it happened again.  Another friend offered to trade me a 20 inch Dob for my 15 because the 20 was getting to difficult for him to move around.  And the offer was for an even swap!!!  The temptation to move up to a large scope without spending more money is worse than offering candy to a baby. 


I was now on my fourth scope ( notice that all were DOBs except the very first one).  The larger scope proved to be as much more impressive as each one of the previous upgrades I had made but I soon discovered why my "FRIEND" was so eager to trade. I had finally got to the point where I couldn't load and unload the base of the larger scope without someone to help me.  But I wasn't about to part with that large scope.  I would either have to revert to taking the smaller 8 inch scope I had originally purchased to star parties away from my house or just not take a scope .  Neither of these options made me feel very good.  


Suddenly out of nowhere my benefactor appeared in shining armour.  Lucy stepped up and asked the key question---"WHY DON'T YOU BUY A SECOND DOB THAT YOU CAN EASILY HANDLE AND MOVE EASILY IN THE PICKUP?"  How she ever discerned my thoughts I will never know but I am eternally greatful.  It isn't often that your spouse offers to let you spend $1000 dollars for a piece of equipment when you already have somewhere in the vicinity of $2500 dollars tied up in a telescope. In addition to the 20 inch scope I now own a very good 12 inch Dob which serves both as a regular at the house but is my standby for carrying to star parties away from home.  Remember back in 2000 I was trying to justify spending $650 dollars for that very first scope?


Not everyone will make the moves that I have made and continue to buy larger and larger scopes.  You can purchase a very good 8 inch DOB from one of the catalog companies for about $350 dollars and a 10 inch DOB for around $550 dollars.  Either of these scopes are very user friendly and are very functional.  


Many folks will opt for a very inexpensive scope from a department store or some similar retail outlet to give to a young observer or someone just beginning in astronomy.  The idea behind a purchase like this may be to determine if the person will become truly interested in astronomy or if it is just a passing fancy.  I understand the thought behind this rational but it will almost always backfire.  If the scope mount and the scope itself are made of cheap materials they will probably prove to be more of a hinderance than benefit to your potential astronomy observer.  Most of these scopes are less than desirable in overall workmanship and are usually very hard to use.  The tripod may be very lightweight and unable to hold the telescope without continual shaking.  No matter how good the telescope may be, if the mount it is on is loose and wobbly you will never be able to see very much in the eyepiece.  In a majority of  scopes of this quality the focus mechanism will never allow you to get a object into good focus because the gearing is not very well machined.  It's a lot like a small bolt in a large hole---it just flops around and is never very solid.  There will be a lot of "department store" scopes for sale this Christmas season and many of them will be advertised as "computerized".  These scopes will sell for something around $99/$350 dollars and are very tempting for the first time buyer.  I would never advise you not to purchase one of these scopes.  They may be exactly what you want and need.  What I would advise you to do is this---visit with someone that owns a scope.  Talk to them about the likes and dislikes of their scope.  If possible, try using the scope to see how it works for you.  Better yet, if possible, visit a astronomy club one night when they are observing.  They will likely have several scopes representing all types and sizes.  They may not all agree on the one best scope but at least you can get the pros and cons from more than one person.  If you decide that observing is the thing you want to do or if someone in your family wants to get into observing, then go out and find yourself a telescope.  If you are still undecided and want to investigate still more before you make a purchase, consider buying a good pair of binoculars.   There is an untold number of objects than you can observe with binoculars alone.  At least if you decide that star gazing isn't for you, the binoculars can be used for a lot of other activities.















  

TOTAL MOON ECLIPSE DECEMBER 10, 2011

Well it is true that there will be a total eclipse of the moon on December 10th of this year but unfortunately for us around the LASS site it is going to be a short look.  The penumbra stage will begin at 5:33 AM (plus or minus a minute of two) and the moon will set in the west (where else does the moon set?)  at about 6:45 AM.  The moon will not be in a total eclipse until 8:06 AM. It will already be below the western horizon from our viewing point by that time so we won't see the whole eclipse. 
I know that most of you that read this blog know that a lunar (moon) eclipse can only happen during or very near the full moon phase.  That is the only time that the earth could possibly be positioned between the Sun and the moon. Technically, it would be possible to have a full lunar eclipse every month but in actually it only happens about twice every year.  And even then it isn't visible to everyone.  It is a little difficult for me to explain this since I can't easily use my hands to illustrate all the many in's and out's of a lunar eclipse in this blog but a casual glance at the illustration here will give you something to hang onto while I attempt to explain the phenomenon. 

Under the conditions shown at the left, the moon is in the full shadow of the earth and therefore is in a full eclipse, at least to folks in some parts of the world. Needless to say, if you can't see the moon at all because it isn't visible to your location during the time that it is in the earth's shadow, you aren't going to see any part of the eclipse. That is the case on the Dec 10th eclipse for us in the Texas area of the U.S.  For us, the eclipse begins early in the AM hours of the 10th and it just so happens that the moon will be setting in the west from our viewpoint at that time of the morning.  We will be able to see part of the earth's shadow as it covers the moon but only for a short period.  If you are lucky enough(?????) to live in Calif you could see the entire eclipse.


Since we have been talking about a "full eclipse", someone might want to know what other kinds of eclipses are there out there?  Simply stated, there is either a full eclipse or a partial one. The partial one could be anything just short of the moon being in the full shadow of earth to something as slight as just what we might call a slight brush.  What then is the thing that prevents all eclipses from being the full blown thing? 

Without trying to get to technical, here is the simple explanation. During its orbit of the sun, the earth follows a path called the "ecliptic". Since the moon is a satellite of earth, it also follows this "ecliptic" with a slight variation.  That variation amounts to approximately 5 degrees variance from that of the earth's ecliptic. Looking at the sketch above, you can see that there is an intersecting line between the earth's ecliptic and the moon's orbit around the earth. The point of this intersection is called "Nodes" and there is a northern and a southern node. In order to have any kind of lunar eclipse the moon must be at the northern or southern node and at the same time the earth must be between the moon and the sun.  It stands to reason that there is always a shadow effect from the sun/earth relationship ( how else could day and night be possible?) but unless there is some object for that shadow to fall upon we only recognize it as night time. The moon does make this critical shadow alignment on the average of every six (6) months hence a lunar eclipse every six months. Sometimes the alignment isn't always perfect therefore we see only a partial eclipse. Always keep this fact in mind---if your can't see the moon from your vantage point when it goes thru all these gyrations, you will not see the eclipse.


 If all of this confuses you just come to one of our LASS observing parties.  I can demonstrate the entire process to you in 3 minutes using a couple of balls and a flashlight. If you need a fully scientific explanation, Google "lunar eclipse" and follow the various articles.  HAVE FUN