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Although the authors have no doubt embellished this one, it sounds very like a supernova, and indeed there was an explosion in this year.

Merely a nova I'm afraid. The star coughs and throws off waste material from the surface, resulting in a bright flare. Such things are rare enough, but supernova (The complete destruction of a star) is incredibly rare - I did read of one expert who reckoned there's been three during the life of our galaxy. In any case, an observable supernova had better be a long way off because the explosion has dire consequences for nearby star systems.

 

 

So, are you saying that the Crab Nebula and such others are only the results of novae and not supernovae? I have to confess I haven't read any up-to-date stuff on astronomy for a while, so this interests me, Caldrail. From my reading years ago I always thought the main nebulae in our galaxy and others were the results of supernovae. Has research proved otherwise now? And I had heard that Betelgeuze (?sp) in Orion was going to be the next big supernova. Have you any up-to-date info on this? It's an unstable red giant, but will it be a mere nova when it goes, or a big blast?

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Which mesopotamian king? Surely his weaponsmith did the work and not him? In any case, such remains are scarce and not so easily found. Remember that a large-ish meteor doesn't simply drop on the ground. It creates a sizeable crater and usually buries itself under the debris. Its a large metallic stone travelling at high speed, much higher than a catapult stone. And where did you get the story that the sword made from it was stronger? My guess is thats a piece of ancient hype. If they can work meteoric iron to create a sword, they can create iron swords of mundane origin.

 

 

History class, but then again i could be wrong.

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Although the authors have no doubt embellished this one, it sounds very like a supernova, and indeed there was an explosion in this year.

Merely a nova I'm afraid. The star coughs and throws off waste material from the surface, resulting in a bright flare. Such things are rare enough, but supernova (The complete destruction of a star) is incredibly rare - I did read of one expert who reckoned there's been three during the life of our galaxy. In any case, an observable supernova had better be a long way off because the explosion has dire consequences for nearby star systems.

So, are you saying that the Crab Nebula and such others are only the results of novae and not supernovae? I have to confess I haven't read any up-to-date stuff on astronomy for a while, so this interests me, Caldrail. From my reading years ago I always thought the main nebulae in our galaxy and others were the results of supernovae. Has research proved otherwise now? And I had heard that Betelgeuze (?sp) in Orion was going to be the next big supernova. Have you any up-to-date info on this? It's an unstable red giant, but will it be a mere nova when it goes, or a big blast?

Its a question of scale, and many reports of these things are written by people who don't understand the difference between the two events. It may well be that Betelgeuse is primed and ready I'll check into this for you if I still have the info to hand.

 

------======######======------

 

No, sadly I don't have that info anynore. From what I remember there's only a limited range of stars that have the potential for supernova, and its not a sure thing that they will. For a general definition then, a nova is an explosion that does not destroy the star, the supernova on the other hand does. You are right though, the Crab Nebula is apparently the smoking evidence of such a supernova, although I understand a pulsar is still there in the center. Its difficult to appreciate how vast such an explosion is. Think of the bombs that flattened Hiroshima and Nagasaki. Now make that bomb sun-sized, thousands of times bigger than the earth. Now make that a giant star, less stable than our own. Get the picture? Thats one BIG explosion!

Edited by caldrail

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Ah Caldrail... a meteor is any stellar object that is visibly seen to pass through the Earth's atmosphere and burns up whether leaving a trail or not. It can be any size too - from as small as a speck of dust to a larger rock usually. A meteorite on the other hand is an object that falls as a meteor but eventually reaches the Earth's surface. It does not have to be found either as it can disintegrate on impact. A meteor shower is an annual event usually seen on the same dates roughly every year. These will build up in intensity over anything from a few days to a couple of months. It depends upon our passage through the debris of the object that has cast its particles in a narrow or wide band of space. Over time this will widen. A meteor storm reults from our traversing through a very thick field of debris and these events are rare.

 

I could go into more detail if anyone wished but that is sufficient to explain what these things are. I studied meteor showers for many years and have spoken to some of the worlds leading authorities on this subject too but in latter years my interest in Roman History and too many cold nights have allowed that to take a back seat.

 

I hope that helps... sorry if I sound like a teacher!!

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Ah Caldrail... a meteor is any stellar object that is visibly seen to pass through the Earth's atmosphere and burns up whether leaving a trail or not. It can be any size too - from as small as a speck of dust to a larger rock usually. A meteorite on the other hand is an object that falls as a meteor but eventually reaches the Earth's surface. It does not have to be found either as it can disintegrate on impact. A meteor shower is an annual event usually seen on the same dates roughly every year. These will build up in intensity over anything from a few days to a couple of months. It depends upon our passage through the debris of the object that has cast its particles in a narrow or wide band of space. Over time this will widen. A meteor storm reults from our traversing through a very thick field of debris and these events are rare.

 

I could go into more detail if anyone wished but that is sufficient to explain what these things are. I studied meteor showers for many years and have spoken to some of the worlds leading authorities on this subject too but in latter years my interest in Roman History and too many cold nights have allowed that to take a back seat.

 

I hope that helps... sorry if I sound like a teacher!!

Meteorite showers are commonplace. Tons of material falls on earth every day. We have bits of the moon and mars dropping on us for instance. How? Because they suffer meteorite strikes too, and without the thicker atmosphere to burn these objects down before collision, and the weaker gravity, debris from these craters can travel into our gravity field. Look into the night sky (preferably away from a built up area with its light pollution) and you may well see the odd meteorite falling. It appears as a speck of light - hence the phrase 'falling star'. A meteor is essentially the same phenomenon but on a larger scale and definitely more impressive to look at, which is why it has its own name.

 

Perhaps you might consider some revision? :romansoldier:

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It appears there are some Astronomy buffs amongst the Romans here at UNRV particularly those who like to enjoy the naked eye variety; no telescopes and gear to set up, just the self to attend to. Sometimes events occur that almost rival a minor meteor shower in excitement. Here's a preview of the early morning sky of Wednesday October 3rd thru Sunday the 7th of October and beyond.

 

In early October, bright orange Mars rises before midnight. On October 3, the Red Planet rises with a Last Quarter Moon and stands within a degree - less than 2 Moon-diameters - of Gemini's fine open cluster, M35. Take a long look at this wonderful arrangement through binoculars.

 

Between October 7 and 12, Mars passes north of Eta and Mu GEMINorum. The planet's eastward motion slows daily as Earth closes and prepares to overtake it.

 

Mars is bright, reaching magnitude -0.6 by month's end. The Red Planet's brightness and color beautifully complement magnitude 0.4 Betelgeuse, nearly 20

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Ah Caldrail... a meteor is any stellar object that is visibly seen to pass through the Earth's atmosphere and burns up whether leaving a trail or not. It can be any size too - from as small as a speck of dust to a larger rock usually. A meteorite on the other hand is an object that falls as a meteor but eventually reaches the Earth's surface. It does not have to be found either as it can disintegrate on impact. A meteor shower is an annual event usually seen on the same dates roughly every year. These will build up in intensity over anything from a few days to a couple of months. It depends upon our passage through the debris of the object that has cast its particles in a narrow or wide band of space. Over time this will widen. A meteor storm reults from our traversing through a very thick field of debris and these events are rare.

 

I could go into more detail if anyone wished but that is sufficient to explain what these things are. I studied meteor showers for many years and have spoken to some of the worlds leading authorities on this subject too but in latter years my interest in Roman History and too many cold nights have allowed that to take a back seat.

 

I hope that helps... sorry if I sound like a teacher!!

Meteorite showers are commonplace. Tons of material falls on earth every day. We have bits of the moon and mars dropping on us for instance. How? Because they suffer meteorite strikes too, and without the thicker atmosphere to burn these objects down before collision, and the weaker gravity, debris from these craters can travel into our gravity field. Look into the night sky (preferably away from a built up area with its light pollution) and you may well see the odd meteorite falling. It appears as a speck of light - hence the phrase 'falling star'. A meteor is essentially the same phenomenon but on a larger scale and definitely more impressive to look at, which is why it has its own name.

 

Perhaps you might consider some revision? :)

 

Dearest Caldrail

 

I will take your words bit by bit and correct you. While I am impressed with your knowledge of Roman History you really need to do some revision yourself when it comes to astronomy. Your terms are wrongly interpreted.

 

'Meteorite showers are commonplace.' If this were so many more people would be hit with them as these are the objects that fall to Earth. Your term should be 'meteor shower'.

 

'Tons of material falls on earth every day.' Correct. And most of these are called micrometeorites!

 

'We have bits of the moon and mars dropping on us for instance. How? Because they suffer meteorite strikes too, and without the thicker atmosphere to burn these objects down before collision, and the weaker gravity, debris from these craters can travel into our gravity field.' Partly true. We do have stuff from all over space hitting the atmosphere but well over 90% of it burns up before hitting the Earth's surface.

 

'Look into the night sky (preferably away from a built up area with its light pollution) and you may well see the odd meteorite falling. It appears as a speck of light - hence the phrase 'falling star'.' While your advice here is correct about light pollution the latter part is incorrect. You are unlikely to see this happening. It is very rare to visibly 'see' what is eventually a meteorite fall to the Earth. What you describe is a meteor... commonly dubbed either a 'shooting star' or 'falling star'. Another one is an ancient term and was classed as the 'tears of the Gods'. A meteor does appear as a speck of light (at first) but you forgot to mention it streaks across the sky so a speck is strictly wrong and so is known as a 'streak' or 'stream'.

 

'A meteor is essentially the same phenomenon but on a larger scale and definitely more impressive to look at, which is why it has its own name.' Please see my earlier descriptions of these objects as I do not wish to repeat myself. However, the 'more impressive' meteor you mention has a different name altogether. This is a fireball and is anything really brighter than a magnitude of -5 in stellar terms. Another bigger object is that of a bolide. This is an audible phenomenon and an explosion can be heard from it as it disintegrates in the atmosphere. This is even more rare. Fireballs, if seen, should be reported as soon as possible as this is where possible METEORITE debris can be found at the end of the reported path of trajectory through the atmosphere.

 

And so endeth a lesson!! Please do read up on this Caldrail as I assure you I am perfectly correct. I stated I studied this phenomenon for years and one does not need to revise as one does not forget terms that do not change. I was actually noted in the British Astronomical Associations Journals as having provided an accurate magnitude, time, path and speed for an event which led to the discovery of some extremely important meteorite material after it impacted Earth.

 

One other point I have not stated is that away from the meteor showers and all other descriptions above we have one other - a sporadic meteor. This term is given to a single meteor that is not associated with any shower and can appear anytime and anywhere in the night sky. These are far more common than you would think and by far outweigh the numbers of shower meteors on years where average displays are noted from all showers.

 

Have a read of a good astronomy book and come back and tell me what I know... I am correct!! Sorry Caldrail to do that but I feel my integrity and knowledge were being put to your Roman sword so I had to put up my Roman shield!! :)

Edited by Augustus Caesar

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Augustus Caesar, Cladrail, and all who get excited by meteor showers, since this topic has been enlivened I'd like to further comment. There are events that vastly exceed an ordinary meteor shower, and when witnessed can be life altering. What follows is a post I made at Astronomy.com.forum under the topic Extreme Astronomy: (As follows)

 

60,000 Meteors per Hour!

 

Meteor Showers can be thrilling. Even seeing 1 or two nice so called "falling stars" can be a thrill. I know they are for me. I was deeply influenced to become an amateur astronomer because of an event visible to all who may have been alive on the night of October 9, (a Wednesday), 1946.

 

Depending on weather conditions at an observers location, as is always the case for things astronomical, those who were alert to the sky on that night would have seen what I saw at the young age of 5 years. It was both awe inspiring and traumatic, for someone so young. Others that I know of who saw it, claim to have seen what I saw but weren't as moved by it as I was. That's probably because all those other witnesseswere somewhat older than I at the time.

 

In my copy of Field Guide to the Stars and Planets (Menzel) 1964 there is a table (#21) titled Meteor Showers. Listed there are all the periodic meteor showers and also certain ephemeral events that are called Meteor Storms. The comet associated with the event of that night is Comet Giacobini-Zinner. The meteors which also become visible at the passing through Earth orbit of Comet G-Z are called Giacobinids.

 

On the night of 9-OCT-46 the chart shows approximately 1,000 meteors (falling stars) per hour. In an earlier event in 1933 the table shows 20,000 objects per hour. (other subsequent apparitions have been non events). My own estimate (even though at 5 years of age) is closer to 60,000 per hour. I base my estimate on the memory of meteors being visible in all parts of the sky, and that anywhere one looked the sky was literally crawling with moving, falling-star like objects.

 

The official estimate of one thousand objects/hour in the whole bowl of sky would only account for less than one object a second, (20,000 / 3600 sec/hr = .277 objects in any 1-second of viewing or one object every 3-1/2 seconds). That's an immensely long span of time for an observer seeing what I saw that night. A couple hundred moving objects in the entire sky per second would yield 72,000 objects per hour. I can accept 60,000 per hour, then, as being reasonably close to what I saw that night.

 

Consider that that would only be 17 objects visible per second, and only one per 6/100's of a second.

 

Observing an event such as the one I've just described would tend to make one a constant observer of the night sky. ... And would influence the observer to an unusual level of interest in astronomy.

 

Because of that experience, all my life I've made it a point to go out on any clear night and take a look at the night sky and check it out. Like many of you, I consider the stars my constant companions, and yes my friends. Because of them I don't need many others. As an alert and skeptical observor, I can say that with all those many hours of observations, I have never seen a phenomena that could not be explained by more or less prosaic astronomical facts. I have never seen something that made me wonder if I'd seen a UFO or the like.

 

I did once in the middle of the day see what I would have to call a very large meteor (bolide?) pass from south to north across Indiana Skies, visible for long seconds, across the entire sky and appear to be deflected back into space. My memory is that that happened about the year 1991.

 

Besides the Meteor Storm, first mentioned, I observed what appeared to be a constant flux of many small meteors in the high desert night sky of California and particularly at the skies zenith, just at the edge of visibility. Is this a common occurance? See my comment under Extreme Astronomy after the post of jkade "observing from above the clouds" Americanbottoms 2007/8/19 8:31 PM being my comment:

http://www.astronomy.com/ASY/CS/forums/351896/ShowPost.aspx

 

Go there for details if further interested.

 

Exciting Viewing, and Clear Skies to you all!

 

FAUSTUS

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Faustus

 

Hi... I envy you enormously living in a country where you can get away from light pollution without too much difficulty. Here in England there are so few spots that can be truly rewarding it is quite sad. However, witnessing a storm of the ilk you describe would be a dream come true for me although I would hardly be able to count the darned things!! That would be of little importance to a casual observer and not much of an important thing to myself either unless I had a camera to measure the activity. I remember many years ago watching a Perseid shower that was one of the best recorded in modern times. I recorded 117 meteors in one hour and you may think that is trivial. In some ways yes it is but as the light around me was quite bright I found that a remarkable figure as did the BAA officials I sent my report in to. It was the highest figure obtained nationally on that night which was quite a result for me. It doesn't really matter what numbers you see really or record - it is down to the absolute majesty of seeing a streak of light silently glide across the firmament and within a second or two completely vanish only for the anticipation of seeing another build into a frenzy when a shower reaches its peak. Part of the excitement is when you observe when no shower activity is present and one spots several sporadic meteors. This is either tantalisingly a small number or better still about a dozen per hour. You never know where or when they are coming and they appear from all parts of the heavens. Absolutely magnificent.

 

I took my wife out to observe this phenomenon for her first time and she fell in love with them. It thrills her even now after all these years as a non astronomer to see something just catch the vision for a second or so and disappear leaving her with the satisfaction that another piece of heavenly magic has set off a spark which makes her want to stay and see more. We have witnessed a shower together too and that makes me feel proud. This is one of the last bastions of astronomy that the professionals cannot really take away from the amateur and the awesome displays make each observation so worthwhile.

 

You mention a book by a guy called Menzel... Donald that is. That book was one of the first I ever bought and I still have it. It is a first edition. I treat it with so much respect. An excellent book. The table is by no means a full one though. The BAA yearbooks give a fuller table and even that omits some of the lesser known minor showers. But what the heck!! Who really cares? If you wanna know them you'll find them and observe them anyway.

 

Good watching Faustus!! I may just go out again one of these winter nights when it is so cold and I may take my wife and a flask too... I look forward to it! :suprise:

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Salve A.C.

 

It's always great to run across other amateur Astronomers, and there seem to be a few here at UNRV. Most people are not aware of the serious work in Astronomy amateurs do as the professionals are busy doing the "serious" work. If you followed my link to the Astronomy.com Forums, you can see that it's an active field for people who wonder about the most universal science of them all, and the one we all share a visual part of practically every day.

 

Some of us have slightly incorrect conceptions and nomenclature for things in our favorite science, but it's the enthusiasm that is important. We can all head back to our favorite book sources to brush up, and be reminded of things we'd forgotten. I feel a small tug at providing some corrective enlightenment here but I'm most pleased at the enthusiasm I see at UNRV for reason and logic as well as history; a great sense of proportion prevails here-abouts.

 

The two three largest sections of my personal library are Ancient Roman History, Astronomy, and Science Fiction (but not necessarily in that order). I presently have all issues of Astronomy Magazine from 1978 through 2007.

 

Astronomy is a very conservative science. As you recall, Astronomers would not seriously discuss Exo-planets until we'd actually found some. We are headed for mapping sunspots on other stars with interferometry(sp?), if we can do that, then planetary bodies will have to come next. It

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Although the authors have no doubt embellished this one, it sounds very like a supernova, and indeed there was an explosion in this year.

Merely a nova I'm afraid. The star coughs and throws off waste material from the surface, resulting in a bright flare. Such things are rare enough, but supernova (The complete destruction of a star) is incredibly rare - I did read of one expert who reckoned there's been three during the life of our galaxy. In any case, an observable supernova had better be a long way off because the explosion has dire consequences for nearby star systems.

 

 

So, are you saying that the Crab Nebula and such others are only the results of novae and not supernovae? I have to confess I haven't read any up-to-date stuff on astronomy for a while, so this interests me, Caldrail. From my reading years ago I always thought the main nebulae in our galaxy and others were the results of supernovae. Has research proved otherwise now? And I had heard that Betelgeuze (?sp) in Orion was going to be the next big supernova. Have you any up-to-date info on this? It's an unstable red giant, but will it be a mere nova when it goes, or a big blast?

Salve, Amici!

 

This official list from the IAU ( International Astronomical Union) shows more than four thousand supernovae http://cfa-www.harvard.edu/iau/lists/Supernovae.html"" target="_blank">Sequitur.

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I could go into more detail if anyone wished but that is sufficient to explain what these things are. I studied meteor showers for many years and have spoken to some of the worlds leading authorities on this subject too but in latter years my interest in Roman History and too many cold nights have allowed that to take a back seat.

 

Have a read of a good astronomy book and come back and tell me what I know... I am correct!! Sorry Caldrail to do that but I feel my integrity and knowledge were being put to your Roman sword so I had to put up my Roman shield!! :ph34r:

 

Careful Augustus.. I sense a little hubris. Your arguement should carry weight, not your own description of your status and qualification. Plenty of people with letters after their name have made fools of themselves simply because they assumed they were right and could not be questioned. Actually I think your knowledge of astronomy is good.. But that doesn't mean you're right. However, since you've wiped the floor with my statement, dunked me in the bucket and cleaned off the dirt, I step back from the floor, sit down, and lick my wounds... :ph34r:

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Calders, Augustus, Faustus - how big are YOUR telescopes - and does size matter? Mines only a little 3 inch refractor, and the equatorial mount is a tad rusty at the moment... :)

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Calders, Augustus, Faustus - how big are YOUR telescopes - and does size matter? Mines only a little 3 inch refractor, and the equatorial mount is a tad rusty at the moment... :)

 

NN

 

Mine is an 8" Meade LX2080 f8 Catadioptic circa 1987 with a slightly rusty motor drive. But no, size doesn't matter as it's all about the eyes when it comes to meteor showers. In an 8' like mine, the moon can almost perfectly fill the field of view at apogee, and at perigee it is quite noticeably smaller, but the best lunar views are during crescent and gibbous phases, then fault lines and mountain shadows are clearly visible. Jupiter's moons can be identified even with a decent pair of binoculars, but a camera tripod can help a lot with binocs.

 

 

Valete, clear skies and good viewing to all

 

Faustus

 

--------------------

 

Ah, Moon of my Delight who know'st no wane,

The Moon of Heav'n is rising once again:

How oft hereafter rising shall she look

Through this same Garden after me---in vain!

Edited by Faustus

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Calders, Augustus, Faustus - how big are YOUR telescopes - and does size matter? Mines only a little 3 inch refractor, and the equatorial mount is a tad rusty at the moment... :(

 

Northern Neil, etal

 

Now that I've displayed my "bragging rights" I think I owe you a more direct answer: Size doesn't really matter. What does matter is Set-Up time, and even storage. If you can build an observatory with a shuttered roof then go for something rrreally large like a 12 or 14" scope, maybe then.

 

When I got my 8", I gave away my Tasco "Jason" 3" refractor scope. Later I wished I hadn't.

Your 3" will do almost everything my larger scope will do, after you get the mount cleaned. A rule I follow as a life long builder is this: when I go to the store to buy a tool, I ask one most important question: What am I not going to like about this? (What is it going to require of me that I am not going to want to do later?)

 

Anyone thinking of buying a larger scope should attend a Star Party. They are held all over the U.S. practically any week-end where amateurs go to show off their scopes with overflowing enthusiasm to share their scopes. Those parties are probably going on near to you. Check HERE (check out community events). Surf a little there and you'll find whatever you want.

 

The best objects for small scopes like ours are: Globular clusters, Open clusters, Double stars, Venus (phases), Jupiter and the dance of its larger moons, Saturn/rings and moons, our own moon and it's phases because it changes daily as to what it reveals. The outer planets are just too small, and more fun to just keep track of with the naked eye.

 

Anything my list doesn't include would be appreciated; what are yours?

 

Another object that is not paid enough attention to is our own sun. Daily there is a sunset during which the sun is naturally filtered by the thick atmosphere of our Earth (but not so good for sunrises as it is rising from the atmosphere's filter). Once i appraise the situation with my unprotected eye, I often take a look at it then with my binocs to look for sunspots. They rotate with the sun's surface rotation speed of 25.7 days at its equator and down to 33.4 days at 75 degrees N. & S, latitudes with variation in between, entering on the left and exiting on the right. I also keep a piece of dark filter glass over the eyepiece of an old pair of binocs with the other eyepiece taped over many times with duct tape. When the tape brightens up I know I'm close to alignment with the sun, making it easier to find. Now that I've said all that I'm obliged to issue a warning: observe eye safety!

 

 

Valete --

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