Astronomy Question of the Week 02/05

[tfwthom]

Lets try this one:<br /><br /><span method="POST" action="/dopoll.php"></span> <div class="Discussion_UserSignature"> <font size="1" color="#3366ff">www.siriuslookers.org</font> </div>

 

[harmonicaman]

Great question! Very tricky; I think you could actually argue the case for either answer...

 

[newtonian]

TFWThom - It is my understanding the tail is always away from the sun, but comets are not always travelling towards the sun - so I stuck my neck out (no tail available) and said false.<br /><br />However, if the comet is travelling faster than the solar wind speed.....?

 

[Saiph]

here's my hint:<br /><br />The question says only that "<i>a</i>" tail points away from the sun. <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>

 

[alokmohan]

Yes .IT POINTS OUT.NO CONFUSION.

 

[harmonicaman]

Comets have ions tails and dust tails. I agree that the ion tail always points away from the sun, but what about the dust tail? <br /><br />Doesn't a comet leave a trail of dust particles in its wake which we observe as annual meteor showers when the Earth crosses the comet's orbit? Couldn't this be considered a "Tail" trailing behind the comet?

 

[abhinavkumar_iitr05]

Actually the question reads out as the tail is always behind the comet's head which is always not true.Its always away from the SUN.

 

[tfwthom]

A bump to get this on the 1st page<br /><br /><br />Answer later......... <div class="Discussion_UserSignature"> <font size="1" color="#3366ff">www.siriuslookers.org</font> </div>

 

[newtonian]

TFWThom - Was that a clue?<br /><br />The tail is bumped from its former position by an enlightening source? <br /><br />Dust would also be bumped, not just ions, correct???

 

[rhodan]

<i>A comet has a tail that trails behind as the comet rounds the sun.</i><br /><br />Key is 'as it rounds the sun'. The dust tail would trail behind, because it always points in the direction the comet comes from. The ion tail would point away from the Sun. So, true. <br />

 

[tfwthom]

(Total Votes: 16) <br />True <br /> 5 (31%) <br /> <br />False <br /> 11 (68%) <br /> <br />False<br /><br />Comets do not have tails until they near the Sun. Then, as the heat of the Sun vaporizes the ices that make up the comet, dust and gases escape. These driven off from the head of the comet by solar wind and the pressure of the sunlight, form one or more tails that are pointed away from the Sun. So after the comet has passed the Sun - returning to outer space - the tail will precede the comet until at some distance it will have diminished to nothing.<br /><br />Once thought to be phenomena in our atmosphere, we have known since the observations of Tycho Brahe that they are parts of the Solar System well beyond Earth's atmosphere. Most are on long elliptical orbits (perhaps parabolic in some cases) that take them from the outer reaches of the Solar System to the vicinity of the Sun. If they come near the Sun they are heated and emit gases and dust that are swept by the Solar Wind into the characteristic tail that consequently always points away from the Sun. <br /> <div class="Discussion_UserSignature"> <font size="1" color="#3366ff">www.siriuslookers.org</font> </div>

 

[Saiph]

ahh...so the dust tail is <i>also</i> pushed away a bit? Just not as much as the ion tail? <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>

 

[bobw]

Did you get that one wrong? I got it right but wanted to change my vote the instant I clicked the mouse. I forgot about the dust tail when I voted. Let's hope astronomers find a gravel tail soon <img src="/images/icons/smile.gif" /><br /><br />These quizzes are fun. <div class="Discussion_UserSignature"> </div>

 

[tfwthom]

Glad you enjoy them...they get to be work. Except for the true/false ones I have to figure how to make them multiple choice.<br /><br />And I don't get to answer lol <div class="Discussion_UserSignature"> <font size="1" color="#3366ff">www.siriuslookers.org</font> </div>

 

[bobw]

<font color="yellow">they get to be work</font><br /><br />I have not been able to think of a good one yet. <div class="Discussion_UserSignature"> </div>

 

[tfwthom]

I'm not making up the questions....they are out of a game called Good Heavens! It's an astronomy card game like kind of like Trivia Persuit. Only thing I have to figure out is how to make them multiple choice.<br /><br />I got it for those nights when the clouds ruin the night. Break out the Glenfiddich (or beer or whatever) and some kind of game to pass the time. I pull a camper to observing star parties so carrying chess, cards, and backgammon games and three scopes is nothing. Ask NEVERS lol when the skies get bad it's "Miller Time" and just party. <br /><br /> <div class="Discussion_UserSignature"> <font size="1" color="#3366ff">www.siriuslookers.org</font> </div>

 

[hungrrrry1]

I haven't read everyone's responses so my answer may sound the same as one two or parts of many....<br /><br />It is false...<br /><br />The comets tail would usually move away from the sun regardless if the comet was moving toward it or away...if merely floating through space, dust that may gush from a comet due to freezing, warming, chemical reaction or other would likely still drift with the comet on a similar path except away from the comet...Solar wind would repel this dust and comet out-gassing away from the sun. so as the comet nears the sun the tail is behind (if there is a back end of a comet) the approaching comet as it passes around the tail stays 180 degrees the other side of the comet and then as the comet heads away from the sun the tail is ahead of the comet as it travels back to the region it came from. As I stated, solar wind makes it to earth in like 15 minutes or something like that so it is logical to believe that the dust will travel the way the wind blows, the comet can't even remotely keep up with that.

 

[hungrrrry1]

OK...sorry, now that I have taken the time to read some of the answers and see that the actual answer from this game is actually posted I feel like a dumb/ss for posting...anyways...gotta get back to work.

 

[kauboi]

Not at all, you added useful info and that's what this place is all about. Thanks for your response, it helped the answer to be more complete and 'understandable'.