Mars and Venus Light Intensity

Well Mars is now closer so its light is brighter than Venus(not for
long) Venus reflects white light off its clouds(more intense) where as
Mars reflects red light off its rusty surface. We could interpret red
light as an object being very far away,but not in this case,for we know
why we are seeing red up close. Venus has to be third for reflecting
light,for its close to the sun,has a size close to earth's,and clouds.
We can more easily relate Venus to Earth than to Mars. However there is
life on Earth but not on Mars or Venus. They could have come close(but
no cigars) Bert

Bert posted:

Well Mars is now closer so its light is brighter than Venus

No Bert. Mars is not as bright as Venus. Venus right now is magnitude -3.9,
while Mars is -2.8. This makes Venus over two and a half times brighter than
Mars is now. With negative magnitudes, the higher the number's value, the
brighter the object is, which is opposite of the fainter "positive" magnitudes.

Venus has to be third for reflecting
light,

Venus has the highest albedo of any planet (0.65). Second place is held by
Jupiter (albedo 0.52), third is held by Uranus (albedo 0.51), and Saturn is in
fourth place with an albedo of 0.47.
--
David W. Knisely
Prairie Astronomy Club: http://www.prairieastronomyclub.org
Hyde Memorial Observatory: http://www.hydeobservatory.info/

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The Earth and the moon must make for great intensity. Its to bad Venus
does not have a large moon,240 thousand miles away. Mars little
asteroids don't do anything. I find calling them moons makes little
sense. Just a thought as seen from Mars would the Earth moon make the
Earth appear to have a moving bulge,or could a 10"" telescope show there
is space between them. Bert

G=EMC^2 Glazier wrote:

Just a thought as seen from Mars would the Earth moon make the
Earth appear to have a moving bulge,or could a 10"" telescope show there
is space between them. Bert

I think that from Mars you'd often have trouble just getting both the
earth and the moon into the same high-power field. Consider that the
distance between the two averages about thirty times the diameter of
the earth, or over a hundred times the diameter of the moon. Right
about now, near inferior conjunction (our opposition) and with the
moon near first quarter, the earth and moon would appear something
like 24' apart. This may not sound like much, but even the naked eye
can resolve objects with only a couple of arc-minutes of separation.
Although 24' must be close to the maximum possible, Terra and Luna
would only rarely be hard to 'split' as seen from Mars, with little
if any optical aid.

--
Odysseus

Odysseus wrote in message ...
G=EMC^2 Glazier wrote:

Just a thought as seen from Mars would the Earth moon make the
Earth appear to have a moving bulge,or could a 10"" telescope show there
is space between them. Bert

I think that from Mars you'd often have trouble just getting both the
earth and the moon into the same high-power field. Consider that the
distance between the two averages about thirty times the diameter of
the earth, or over a hundred times the diameter of the moon. Right
about now, near inferior conjunction (our opposition) and with the
moon near first quarter, the earth and moon would appear something
like 24' apart.

For comparison, the diameter of the Moon as seen from Earth is about
30'. The Earth-Moon separation is trivial to see from Mars; they'd
look like a double planet, with a very bright Earth and a fairly dim
Moon. Through a telescope they'd show phases, like Venus does to
Earth.

When Jupiter is at Martian opposition, in fact, a person on the
surface of Mars could very probably see both Ganymede and Callisto.

Add to that the fact that one of the Martian moons goes backwards
across the sky, and the other takes a day and a half from rising to
setting... something like a half dozen asteroids at least are
naked-eye visible, at different times... and you realize the Martian
sky is enormously interesting compared to ours.

(In fact, other than -- obviously -- Venus, and some of the Centaurs
and Kuypers, you'd be hard-pressed to find anyplace in the solar
system with a sky as dull as ours.)

(G=EMC^2 Glazier) wrote in message ...
Well Mars is now closer so its light is brighter than Venus(not for
long) Venus reflects white light off its clouds(more intense) where as
Mars reflects red light off its rusty surface. We could interpret red
light as an object being very far away,but not in this case,for we know
why we are seeing red up close. Venus has to be third for reflecting
light,for its close to the sun,has a size close to earth's,and clouds.
We can more easily relate Venus to Earth than to Mars. However there is
life on Earth but not on Mars or Venus. They could have come close(but
no cigars) Bert

Bert, not to be insulting or anything, but as far as I can tell you
never have a single clue what you're talking about.

Mars is dimmer than Venus, even now, because (a) its albedo is a lot
lower than Venus', (b) it has about a third the surface area of Venus,
and (c) it gets about a quarter the sunlight Venus does. This
multiplies out to about a twentieth of the absolute brightness of
Venus... ameliorated somewhat by the fact that when Venus is close to
us, we see only a lit crescent. Still, Venus is always several times
as bright as Mars ever gets.

eyelessgame

In message ,
eyelessgame writes

(In fact, other than -- obviously -- Venus, and some of the Centaurs
and Kuypers, you'd be hard-pressed to find anyplace in the solar
system with a sky as dull as ours.)

Maybe, but for the moment this is the only place with anyone enjoying
the view.
--
"Forty millions of miles it was from us, more than forty millions of miles of
void"

Of course there's this http://www.msss.com/mars_images/moc/2003/05/22/



"Odysseus" wrote in message
...
G=EMC^2 Glazier wrote:

Just a thought as seen from Mars would the Earth moon make the
Earth appear to have a moving bulge,or could a 10"" telescope show there
is space between them. Bert

I think that from Mars you'd often have trouble just getting both the
earth and the moon into the same high-power field. Consider that the
distance between the two averages about thirty times the diameter of
the earth, or over a hundred times the diameter of the moon. Right
about now, near inferior conjunction (our opposition) and with the
moon near first quarter, the earth and moon would appear something
like 24' apart. This may not sound like much, but even the naked eye
can resolve objects with only a couple of arc-minutes of separation.
Although 24' must be close to the maximum possible, Terra and Luna
would only rarely be hard to 'split' as seen from Mars, with little
if any optical aid.

--
Odysseus

(G=EMC^2 Glazier) wrote in message ...
We could interpret red light as an object being very far away

What would lead you to that assumption? There is no relationship
between color and distance whatsoever. You might in an uninformed way
be thinking about cosmological "red shift" which is an altogether
different animal.

Hi Odysseus and Bill N Thanks bill that is the first time I've seen
those pictures and are saving them. Odysseus that is good to know that
just with our eyes we can see both the earth and moon separation from
Mars. Bert