What star is this?

[brocks]

@Second

Even with everyone in the thread agreeing that it’s Jupiter I’m still a wee bit skeptical. I thought Jupiter was not able to been seen with the naked eye?

And even if you could see it with the naked eye, that it would be so bright as to outshine all the other stars, even Sirius?

Jupiter’s brightness varies with its distance, but even at its worst, it’s a little brighter than Sirius. It’s current apparent magnitude is about -2.5, which means it’s about 2.5 times as bright as Sirius.

(The numbers are a coincidence. Sirius is about magnitude -1.5, and a difference of 1 in magnitude translates to a 2.512 factor in brightness.)

[Ludovic]

@Colophon

The teacher scoffed at that and said something like “Nice imagination, I think Colophon has been out in his spaceship…” :dubious:

If you had above-average eyesight or were in a very dark location you could have responded “no, it’s true! I even saw Uranus last night!”

[DesertDog]

@Colophon

The teacher scoffed at that and said something like “Nice imagination, I think Colophon has been out in his spaceship…” :dubious:

Teachers like that should be decapitated and their heads left on a pike. They obviously aren’t using their brains so they’ll never miss their noggin. No wonder kids hate scjence.

[K364]

Here’s an interesting table of “apparent magnitude” http://en.wikipedia.org/wiki/Apparent_magnitude#Table_of_notable_celestial_objects

note - less is brighter

Venus…Max: -4.89 Min: -3.82
Jupiter…Max: -2.94 Min: -1.61
Mars…Max: -2.91 Min: +1.84
Mercury…Max: -2.45 Min: +5.73
Sirius…Max: -1.47
Canopus…Max: -0.72
Saturn…Max: -0.49 Min: +1.47
α Centauri…Max: -0.27
Arcturus…Max: -0.24
Vesta…Max: +5.14
Uranus…Max: +5.32 Min: +5.95
Neptune…Max: +7.78 Min: +8.02

[cmyk]

@wedgehed

Where does Mars fit in?

Speaking of Mars, I know it’s called the Red Planet, I know that people often describe its reddish light, but I’ve never been able to discern a reddish color when I see Mars. Does it vary or are my eyes bad?

:smack:

It’s only very slightly “orangish”… and I mean slightly. But it is discernible.

Also, Mercury is harder to catch than the rest of the planets, since it hangs so tight to the sun (as does Venus, being an inner planet… but it’s bigger and farther out so it’s easier to catch). So it can only be seen at sunrise or sunset, assuming it’s not too close to the sun, or behind it from our vantage.

[brocks]

@wedgehed

Speaking of Mars, I know it’s called the Red Planet, I know that people often describe its reddish light, but I’ve never been able to discern a reddish color when I see Mars. Does it vary or are my eyes bad?

Look at it through binoculars. Even a cheap pair makes the color much easier to see.

[cmyk]

I’ll second that. Binoculars are a must-have, even over a telescope, whether you’re a casual star(planet)-gazer, or even a pro.

[standingwave]

@wedgehed

Where does Mars fit in?

Speaking of Mars, I know it’s called the Red Planet, I know that people often describe its reddish light, but I’ve never been able to discern a reddish color when I see Mars. Does it vary or are my eyes bad?

The eye’s cones (the cells that detect color) aren’t as sensitive as the rods so they require more light. Catch Mars at opposition (closest approach) sometime and you should be able to discern color. Opposition occurs every 26 months and the next one will be in March. No other planet has such a wide range of distance from Earth. Mars is 1.4 AU from the Sun (Earth is 1.0 AU) so when Mars is at opposition, it’s 0.4 AU from Earth. But when Mars is on the other side of the Sun, it’s 2.4AU distant (1 + 1.4).