BEGINNERS' STARGAZING QUIZ (QM) - IPY

[onewithnature]

A NEW QUIZ FOR THOSE WHO GASP UNCONTROLLABLY WHEN THEY LOOK SKYWARDS ON A CLEAR NIGHT. IT COULD BE THE KAROO OR KRUGER OR KGALAGADI, OR JUST ANY PLACE WHERE THE STARS CAN BE CLEARLY SEEN!

ENJOY THIS JOURNEY THROUGH SPACE - I'LL BRING YOU THE NIGHT HIT-PARADE FOR ALL OF YOU TO THRILL OVER ...

LET'S BEGIN, OH HEAVENLY MITES:

[onewithnature]

A brilliantly clear night in Satara, you have just finished braaiing outside your chalet, which you managed to procure in a position almost next to the fence. Your day was spectacular – a pride of 12 healthy lion lying on the S100; a large-tuskered elephant bull in musk that mock-charged you twice (you hoped it was a mock charge, to justify your decision to hang around and take awesome pictures); a herd of around 300 zebra, interspersed with perhaps 200 wildebeest in the vicinity of the S90; and something you have never seen before – two caracal kittens peeping their tiny heads out from behind a large rock. You are in Paradise, and you know it.

Then, just when you think it cannot get any better, your girlfriend of two weeks takes you by the hand and whispers that the two of you take a stroll along the fence to see if there are any nocturnals sneaking along. You are only too happy to do so, and with sated stomach and a Cheshire-cat grin on your face, you interlace your hands with hers and move silently into the darkness.

You know this is it. You've been waiting for this opportunity for a fortnight. You know that all you have to do is dazzle her with your knowledge. But you cannot see anything except the stars, as it is new moon. No problem, you think; you'll just wing it – I mean, how many people really know anything about astronomy! You slip behind her and gently point upwards at the twinkling sky.

“There's the great Scorpion, and his red eye.” You point at a brilliant red star which is about halfway up towards the zenith. She smiles at you and your heart gives a leap. “Wow,” she murmurs, “I've always wanted to see the Scorpion – it's my birth sign, you know?” You didn't know that, but it doesn't matter – you're making an impression, a real impression! “Where's the tail of Scorpius? she asks.
You cannot see a tail, but you know that, if a constellation is rising, then you must be facing east. And so, the tail, which is at the end of the Scorpion, must still be below the horizon. “It's still going to rise over there.” You point at the horizon, continuing, “Maybe we can sneak out later and look for it?” “Mmmmm,” she mutters.

“Oh, and that very bright star over there!” You point at an exceptionally bright, white star just to the right of your red eye. “That's not really a star, you see, but the planet Venus.” “The goddess of Love,” you conclude with rising passion in your voice. She smiles again at you, this time more broadly and definitely more sweetly. You interlace your fingers with hers and move both of your right hands towards the right again. You snuggle up to her and, lowering your voice to almost a whisper, you show her a large cross over the south-eastern horizon. “That cross – that's the Southern Cross. When you're with me you can never be lost because, with that cross (you cross your right arms over her chest), I will always give us direction.” You're making more progress than you hoped, so you murmur to her how you take the length of the longest side of the cross and extrapolate it three times along its longest axis, then drop that point down to the horizon; and, wallah – that is south. All of this talking has given you the opportunity to turn her gently around so that your faces are close and, as she gazes up into your eyes, you lean forward.

Suddenly, she pulls back a little and asks, “My darling. Do you always talk so much rubbish when you're trying to impress me? Why don't you just admit you know nothing about the stars?” You're in shock and hear yourself mumbling some kind of clever excuse like, “Well, I wanted to really make you the star here – it's got nothing to do with those stars, you know.”

She pulls further back in disgust. “You know how much I hate dishonesty!” her voice has risen in pitch and her face is one giant frown. “Just tell me the truth – where did you learn that hogwash?” You have nothing to say; you should have paid much more attention to that book your mother bought you for Christmas all those years ago: “Stargazing for Beginners.” Winging it has brought disaster.

But, then, you wonder if she's bluffing, just to get out of being intimate. “I did tell you the truth,” you try, but you don't get another word in. She turns on you like a Cape Cobra ready to strike:
“That red star is the eye of the bull, Taurus; it has nothing whatsoever to do with Scorpius! And that very bright star on Taurus's right is Sirius, the brightest star in the sky, in the constellation of Orion – Venus is not even up! And, if you knew a little bit about astronomy – like you claim you do – you will know that Scorpius and Orion can never be in the sky at the same time because they're at opposite ends of the Zodiac! And that hogwash about the Southern Cross – Crux is not up at the moment, only the pointers are. You were looking at the False Cross. Even if it was Crux, you extrapolate the longest side five times (four-and-a-half to be precise), not three. Really – if you can lie to me about those things up in the sky so early in our relationship, then what else are you going to lie to me about?”

Your brain is numb and you cannot find anything to say about your behaviour. “But, you never told me you're an astronomer!” you finally blurt out; “That's not fair you know – you strung me along for your fun!”

She looks at you with the sweetest smile again, and you hear her say in the most dulcet voice: “I'm not an astronomer. I've been on the SANParks forum and following onewithnature's Advanced Stargazing Quiz for the last year. All that I know about stargazing comes from him! But, you're in luck: he's coincidentally starting a Beginner's Stargazing Quiz today, and it's for free! All you have to do is follow his questions and answers, and you may one day be able to wow some lady with your expertise. However, Darling – or, should I say, ex-Darling – all you will know for now is that your star has set! Adios.”

You turn away and promise yourself that you will never reveal yourself to be ignorant again. You smile bravely and walk towards the laptop in your now-empty chalet – you go to the SANParks website where you booked this holiday of a lifetime, and find onewithnature's Beginner's Stargazing Quiz. You settle back as the hyaenas cackle outside and begin to read the tutorial on stargazing in this thread. You manage a smile: in a few months, you will be an expert!

[onewithnature]

I have been wanting to initiate a tutorial-based, question-and-answer format for beginners in stargazing for a while now. Today is as good a day as any to begin – most especially because it is my birthday, and I will be honoured to share with all of you what little knowledge of the vast universe I know. Since I was 5 years old, I was astounded by the magnificence of the heavens above. When I learnt of the great distances between us and even the nearest stars – that we are, in essence, gazing up at a time machine of what was, and not how the universe presently is - I realised how insignificant we appear, yet, paradoxically, how significant we really are in the great scheme of it all!

My Advanced Stargazing Quiz (originally the Zodiac Quiz, and more recently the Advanced Zodiac Quiz) has been going strong for just over a year now. I began with the intent of educating on the Zodiac signs, but this soon expanded to the neighbouring constellations. Though I started with the basics, it soon became more involved, especially because of those that responded, and their general enthusiasm for astronomy and the night-time stars.

I have realised that it is difficult for beginners to now begin reading my Advanced Stargazing Quiz from the start, covering reams of information before they become somewhat proficient in identifying various constellations and their stars. Consequently, I have upgraded the old quiz to an advanced status, and it will continue in this format along the lines it always has. Anyone is welcome to participate, but it will be aimed mainly at those who already have a fair degree of understanding of the night skies.

But, here, I now initiate the Beginners Stargazing Quiz. As its name suggests, it is aimed entirely at beginners in stargazing. I will start at the very beginning, assuming that anyone following this thread knows absolutely nothing about stars, constellations, planets, and other heavenly bodies. (Hopefully they will know to look upwards, though – if anyone doesn't know where to look to find the stars, please pm me!) We will progressively learn step-by-step, and this learning will be both practical and slow enough for anyone to keep pace. I aim to keep it as simple as possible, avoiding complicated scientific jargon and unnecessary confusion. (I remember how difficult I initially found it to use star charts and locate even relatively simple patterns in the sky.) Yet, I will try to keep it light-hearted, interesting, and with just the right degree of humour and temptation to keep you on the path of astro-enlightenment.

If you know nothing about stargazing, or just a little, please join me in our pursuit of making sense of the night skies. Because I am based in Johannesburg, I will concentrate on the Southern Hemisphere skies as seen from South Africa. However, because most of what we see here will also be seen in Australia, New Zealand, South America, and the rest of Southern Africa, anyone in those countries are encouraged to also participate. If you let me know your locations, and any adjustments are necessary, I will inform you on how to do that (either by private message, or on the quiz itself if there are several people in one location).

[onewithnature]

Before we start, some guidelines on how to make the most of this thread:

*** I will ask one question every week or so. I will allow several days for everyone interested to post an answer. Please post what you think the answer might be – you will neither be judged, nor criticised in any way! I know that it can sometimes be nerve-racking to participate on an open forum, but you will learn so much more and obtain great enjoyment by doing so! Do your best: then the rest will follow! Once I have received sufficient answers, I will respond and give the correct answer.

*** Once I have answered a question, I will open the subject for discussion. Here I will encourage anyone and everyone to ask questions about the subject at hand. Please don't be shy: there is no such thing as a question that is insignificant - if you don't know the answer, it is important for you to find out! Here also, I encourage those who know a little more about the subject, to add interesting information that may enhance interest. Forumites are welcome to have an open discussion on this thread with each other until I ask the next question. I will act as mediator, and answer any questions posed by you, or add interesting and relevant information as I see fit.

*** Once I am satisfied that we can move on to the next building block of our journey, I will pose a new question, and the process will repeat itself.

*** Please don't feel that you need to run out and buy expensive astronomy and stargazing books. Of course, this may enhance your enthusiasm, but it may also confuse you if you don't have a firm foundation of stargazing. It is not necessary to have even a single book on the subject at this stage, for I will ensure that everyone can participate and understand what is going on!

*** A pair of binoculars will be very useful as it can bring a “WOW” factor to stargazing – it is often astounding how many more stars appear in binoculars, and how one can see objects you didn't even know existed! Every forumite on the SANParks website should, and probably does, own a pair of binoculars because we all go game viewing! However, some guidelines on binoculars for looking at the night-time skies: 7 x 30, 8 x 40, and 10 x 50 binoculars are the most useful. There will be no benefit to increasing the magnification beyond 10 times, as the field of view of what you see will be very narrow, and the natural tremor of one's hands will cause the stars to dance around in the heavens! (Even the 10 x 50 can be heavy to hold for any length of time, and it is recommended that, if you choose this size for stargazing, you mount it on a tripod.)
Also, try not to choose binoculars that have the diameter of the front lens of the binoculars less than 30mm (this is the second value above; e.g. 7 x 30, or 8 x 40), as it will let less light in and the objects you are viewing may appear quite dim. So, 50mm lets in more light than 40mm, which lets in more light than 30mm, and so on.
Binoculars should therefore be chosen to balance the amount of light received through the binocs with the steadiness of the magnification used.
Most of the heavenly objects I will focus on will be clearly visible with the naked eye, whether from a city or out in the country. Occasionally, binoculars will be required, but this would only be necessary much later in our course.

*** If there are several answers that are true for one question, please post one fact at a time, and allow someone else to participate too by adding to your answer. This, I feel, is important so that newbies do not feel intimidated by others that have been on the forum for a longer time.

FANTASTIC! WE'RE READY TO BEGIN! ENJOY THE JOURNEY WITH ME ...

[onewithnature]

Here is your very first question:

BACKGROUND INFORMATION:
When you look upwards at the sky on a clear night, you will be able to see hundreds, if not thousands, of heavenly bodies. Most of these will be stars, but there will also be planets.

DEFINITIONS:
A STAR is a hot, massive, ball of gas in the universe that produces its own light. Our own Sun, and most of the stars you see in the night skies, are stars.
A PLANET is a large, round object made of rock or gas that orbits (travels around) a star. A planet does not produce its own light, but rather reflects the light of the star (which is why we see it).

QUESTION:

NAME TWO WAYS IN WHICH WE CAN EASILY DISTINGUISH BETWEEN A STAR AND A PLANET IN THE NIGHT SKY.
(In other words, when we look at a shining body in the night sky, what do we look for to see if it is a star or a planet?)[/

[Lockie]

...I'll take a shot at this...Is it that a star will twinkle, as it is continuously decomposing, and a planet will be a steady shine?

Gosh I hope this isn't a revolving quiz if I get it right

[onewithnature]

No, Lockie ... this is a QM, which means that I generally ask the questions I want to, and there is no requirement for people who answer them to post a subsequent question. I spent so much time preparing everything, and then I forgot to define what type of quiz it is. So, for clarity, it is not an OQ, nor an RV, but a QM.
I will give other people a chance to also answer, and then I will comment on your answer, Lockie. Thanks for playing.

[Siobain]

Great Quiz OWN! Really looking forward to this.

I agree with Lockie's answer in that the stars have a twinkling shine. Is the movement also
a way to tell the difference, as planets and their moons rotate following close to the ecliptic
whereas stars remain stationary, with the Earth's rotation making them appear to move, so
the planets would move in amongst the stars?

[normana53]

Planets show up in different locations in the sky each night (relative to the stars), while Stars are more or less fixed in reference to each other. Planets will always follow the same general path as the Moon and Sun.

[Josh of the Bushveld]

Great quizz OWN
My answer would also be that stars twinkle whereas planets give a more consistent colour of light.

The other answers on relative position also make sense, since the planets are so much closer.

[JustNature]

great quiz OWN, now to start learning
My answer would also be stars twinkle from gases they are burning and planets are a constant light reflected from the sun, then the planets move as also mentioned

[Timepilot]

You think to highly of my metal capacities Siobain.

I don't think so M367

I get the feeling that OWN is actually looking for people to research and learn here (for heavens sake, I still research and I've been doing this on and off for nearly 40 years ) - especially if there is going to be discussions afterwards

[jaapvandijk]

OWN !!!!!

Im so looking forward in learning step by step!

Many thanks for the huge effort you are putting into this!!!

You mentioned a bino. When you look at a planet with your bino, you should see a small ball, while when you look at a star it will still be only a speck.

Looking forward to the rest!

[onewithnature]

Great stuff to start, indeed, oh astronomically enlightened mites! Nice answers - well thought-out! Since you all took the time to reply, I'm going to add your names to a list of those that participate (at one time or another ... or another and another and another ) in the opening post! This will be updated regularly ... after all, one day, your names will be up in lights in planetariums all around the world, yes - so you all better get used to it!!!

Thanks for playing Lockie, Siobain, normana53, joshilewis, Just Nature, and jaapvandijk! The class of 2010 has begun in style!!

[onewithnature]

To recap the question before I give the answer:

DEFINITIONS:
A STAR is a hot, massive, ball of gas in the universe that produces its own light. Our own Sun, and most of the stars you see in the night skies, are stars.
A PLANET is a large, round object made of rock or gas that orbits (travels around) a star. A planet does not produce its own light, but rather reflects the light of the star (which is why we see it).[/color]

QUESTION:

NAME TWO WAYS IN WHICH WE CAN EASILY DISTINGUISH BETWEEN A STAR AND A PLANET IN THE NIGHT SKY.
(In other words, when we look at a shining body in the night sky, what do we look for to see if it is a star or a planet?)[/[/quote]

Now, to the answer. As always - and especially at the beginning - I'm going to keep it extremely simple. If anyone is still unsure, please do not be shy to ask me again to explain! (If you really don't want to do it via public forum (although, this way, everyone benefits from the question), you're welcome to send me a pm.)

As all of you have said, the easiest way to determine whether a heavenly body (other than the Sun and the Moon and comets and meteors and ... ) is a star or a planet is to see if it twinkles. This is not always a hard-and-fast rule as some large stars may not be easily seen to twinkle, and some of the fainter, distant planets may indeed have a slight twinkle.
But, almost always, if you gaze at a planet, it will shine steadily in the sky. If you look at a star, it will twinkle - that is, it's light will rapidly fade and grow stronger. The main reason for this we will figure out when I open it up for discussion, which I will do after this.

The second way to tell if you are looking at a planet or a star is to, as everyone correctly said, watch to see if it moves relative to the other heavenly bodies. Planets visibly move across the sky relative to other objects, while stars do not. The reason has been already mentioned by an astute astronomy student here, but we will also open that up to discussion to discover why this is.
Of course, the movement is not large enough to see it in one night but, if one watches an object for several nights or even weeks or months, some movement will be noted relative to the other stars around it. In fact, the word "planet" indeed comes from the Greeks, who noted that these heavenly bodies wandered across the skies over the course of the seasons - and so "planet" means "wanderer"!
The outer planets - that is, those that are further from the Sun than Earth is - tend to move slower across the skies the further out they are! So, Mars moves quicker than Jupiter, which moves quicker than Saturn, which moves quicker than Uranus, which moves quicker than Neptune.

So, to summarise:
- Stars generally twinkle, while planets generally shine steadily;
- Stars remain fixed relative to each other and to the background night sky, while planets move across the sky relative to stars (and each other) over the course of time.

There is one other way that one can distinguish (as mentioned by an astute mite): if one looks through a pair of binoculars, planets generally have a ball-shaped appearance, while stars remain twinkling points of light. Of course, the strength and size of the binoculars plays a role in this, and the planets like Uranus and Neptune may be too far away to be seen as a ball of light. Rather, these outer planets would need a small telescope to see it as a clear ball. Nevertheless, for Mercury, Venus, Mars, Jupiter, and Saturn, they generally appear as small balls in a pair of binoculars.

GREAT WORK, ASTUTE ASTRONOMICAL STUDENTS!! GIVE YOURSELVES ALL A BIG HANDCLAP THERE!!! lIKE THIS ... !!!