Anyone see anything in the Sky?

[Deelow]

First of all I'm in Grande Prairie, so people in Calgary my not be looking at the same sky....but can anyone see this big orange star in the sky to the south?

I've talked to a few people with telescopes, they say it looks like it's on fire, other people are saying it's the Space Station.

A) Can you see it in Calgary?
B) What the Hell is it?

[Daradon]

Isn't it Mars?

Mars is closer to the Earth now that it has been for most of human history I believe.

[KevanGuy]

Isn't it just Venus? Or maybe Mars? Im not as up on my Astronomy as I used to be.

edit:But yes, I have noticed it too.

[photon]

Yes, it's Mars. Mars is in the eastern sky and is a distinct orange.

Venus would be more south south west and visible close to sunset.

The easiest way to tell the difference between a star and a planet visibly is if it twinkles. Stars twinkle, planets for the most part do not.

The Space Station orbits very quickly so you would see it move against the field of stars, moving across the sky in a few minutes.

[Buff]

I thought this was going to be a UFO sighting thread. I noticed, here in Lethbridge, what appeared to be Northern lights, only they were in the west.

[evman150]

Like the others said, it's Mars. Other bright objects are a different colour. The brightest being Venus which is yellow, Jupiter which is yellowy as well, and Sirius which is bluey.

For an interesting example of contrast in celestial object colour, look at the constellation of Orion, and observe the two brightest stars, the brightest in the top left and the second brightest in the bottom right. Betelgeuse (A Ori) is a red very cool supergiant star on its way out while Rigel (B Ori) is a blue, hot main sequence star. The different colours can be readily observed.

To get an idea of what I mean by "cool" and "hot", the Sun is average, and it's temperature is ~5800K. A Ori is cool, meaning its temperature is in the neighbourhood of 3500K. B Ori is on the hot side, coming in at ~10000K. So it can be used as a rule that stars in the sky (not planets) that are red are cool, yellow/orange are medium, blue/white are hot.

Sorry, I guess what I wrote has nothing to do with the OP's question. Oh well. I just love stellar evolution and stellar astronomy in general!

[Cowperson]

I live in the country southwest of Calgary and the International Space Station passes over periodically going west to east and crosses the horizon generally within two minutes or so. . . . . so it ain't that!!!

Its an interesting sight to see the Space Shuttle trailing it, two bright dots racing across the sky.

Yes . . . . Mars. See any canals?

Cowperson

[red '00]

I'm gonna have to check this out. Always liked this sort of stuff.

[Neeper]

Actually, I am sure everything twinkles. It doesn't matter if it's a star or planet. It's the layer of ozone that makes the lights look like it's twinkling.

[Eddie Bronze]

I think I saw it?

I read what photon said and looked off my east facing balcony and can see, a orange-like color that does not blink looking southeast? Is that right?

I don't have a telescope.

How many miles away would it be right now? And what kind of glow would it be putting off for us to be able to see it at that amazing distance? I wonder if 'they' can see us?

Sorry folks, it's a bad night for me, I don't see a full moon so Mars must be too close.

[Shazam]

Stars and planets twinkle because of temperature and visibility differences in the atmosphere.

[Cube Inmate]

I was just out looking at Mars in my telescope... I didn't see any canals, but I'm pretty sure I saw a face. Mars is about 0.52 AU (astronomical units) away right now, or about 78 Million km.

Cow... can I come out and use your back yard to do some telescopic viewing? I'll bring beer! It bloody sucks living in the lit-up city

btw: Neeper--nothing to do with ozone...the ozone layer starts some 15+ km above us (sources vary as to actual elevation), and the majority of the twinkling effect is caused by the lowest layers of the atmosphere...just the first few kilometers. This is why observatories are on mountain tops.

Twinkling is mostly caused by the movement of air pockets/currents with different densities. Moving air sucks.

[evman150]

Originally Posted by Eddie Bronze

And what kind of glow would it be putting off for us to be able to see it at that amazing distance? I wonder if 'they' can see us?

Mars does not have a "luminosity". It radiates, but not in the visible spectrum (~5000 Å). It radiates at ~5-10 microns, which is in the infrared.

The only reason we see Mars is because of the light from the Sun that reflects off it. One could figure out how much light is actually recieved per unit area from the reflection of the sun off mars and back to earth.

Just take the cross sectional area of Mars divided by the surface area of the sphere with radius r = mars orbital radius. Multiply this by the luminosity of the Sun ~3.85E26W to get the amount of light hitting Mars per unit time. Now multiple this by the albedo of Mars (sort of a rating of reflectivity; 0<albedo<1), then repeat the cross sectional area/sphere surface area exercise except for the earth mars space (you'd have to take an average, or do it for just one point in the respective orbits. Then you get how much light we actually get from Mars. 'Twould be an interesting exercise.

Edit: There is no they. At least not on Mars.

[evman150]

Originally Posted by Neeper

Actually, I am sure everything twinkles. It doesn't matter if it's a star or planet. It's the layer of ozone that makes the lights look like it's twinkling.

Stars are far away so their angular diameter is tiny. Planets are closer so their angular diameter is WAY bigger (still not really noticable to the naked eye though), even though they are many orders smaller in size. The smaller the angular diameter of the source, the larger the effect atmospheric turbulance has on the source. This can be pictured by thinking of the Moon. The moon doesn't twinkle. Why not? Because it's so big in the sky. Same with the planets.

[MagicallyAdept]

Originally Posted by evman150

Like the others said, it's Mars. Other bright objects are a different colour. The brightest being Venus which is yellow, Jupiter which is yellowy as well, and Sirius which is bluey.

For an interesting example of contrast in celestial object colour, look at the constellation of Orion, and observe the two brightest stars, the brightest in the top left and the second brightest in the bottom right. Betelgeuse (A Ori) is a red very cool supergiant star on its way out while Rigel (B Ori) is a blue, hot main sequence star. The different colours can be readily observed.

To get an idea of what I mean by "cool" and "hot", the Sun is average, and it's temperature is ~5800K. A Ori is cool, meaning its temperature is in the neighbourhood of 3500K. B Ori is on the hot side, coming in at ~10000K. So it can be used as a rule that stars in the sky (not planets) that are red are cool, yellow/orange are medium, blue/white are hot.

Sorry, I guess what I wrote has nothing to do with the OP's question. Oh well. I just love stellar evolution and stellar astronomy in general!

i work in the lighting industry and a hockey forum was the last place i though i would hear anyone talking about colour temperature and kelvins but hey i was wrong. i originally thought you had your numbers the wrong way around but i see you are talking about the actual temperature of the stars. in the film industry we use colour temperature so the higher the K, the cooler the light, weird hey? but i agree astronomy is interesting.

Magic

[Hack&Lube]

International Space Station orbits at like 27,000 KPH so it's not that. The ISS would move through the sky very quickly if you can spot it.

[Bring_Back_Shantz]

Originally Posted by Neeper

Actually, I am sure everything twinkles. It doesn't matter if it's a star or planet. It's the layer of ozone that makes the lights look like it's twinkling.

Close neeper, but it has nothing to do with the ozone. It's just a matter of light refracting through the air. As the air is constantly moving, and there are areas that are hotter/cooler, and more or less dense or polluted, the ammount the light refracts is constantly changing, hence the twinkling.

[Bring_Back_Shantz]

Oops double post.
Oh well.
Plus I've seen a lot of people already put this type of thing up.

[Bobblehead]

My favourite site for figuring out what I am looking at in the sky is the Sky and Telescope Interactive Sky Chart

Just enter in where you are, the time of day, and check out the sky.

[photon]

Stars twinkle (scintillate) because they appear as a point source of light and the refractive shifts of atmospheric disturbance are larger than their visual size. Planets' visual size is larger than the refractive shifts so they don't twinlke. Usually anyway; sometimes if they are low in the sky and there's lots of turbulance then a planet can twinkle.

Star light as also very spatially coherent (similar to a laser) so they also appeal to the eye because we usually don't see that sort of light.