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ObiWan377
2003-Jun-07, 10:45 PM
Mars is approching Earth in August if i'm not mistaken right? THe closest its been in years? Is it any threat to Earth, in any way, shape or form? Like could one of its moons fly into us or mess up our gravity? Stupid question, yes. But i'm just curious. I'm an idiot, as I mentioned before in other forums, when it comes to Astronomy and your help would be appreciated. Thank you.

Glom
2003-Jun-07, 10:47 PM
No.

BigJim
2003-Jun-07, 10:51 PM
No.

aurorae
2003-Jun-08, 01:02 AM
Like could one of its moons fly into us or mess up our gravity? Stupid question, yes.

Methinks you should build a simple scale model of the solar system.

Some ideas on this page:
http://www.astrosociety.org/education/activities/handson.html
specifically, the toilet paper model in the last link.

daver
2003-Jun-08, 01:06 AM
Mars is approching Earth in August if i'm not mistaken right? THe closest its been in years? Is it any threat to Earth, in any way, shape or form? Like could one of its moons fly into us or mess up our gravity? Stupid question, yes. But i'm just curious. I'm an idiot, as I mentioned before in other forums, when it comes to Astronomy and your help would be appreciated. Thank you.

I'll elaborate a bit more over the previous answers. Mars' orbit is fairly elliptical (eccentricity = 0.0934) (Earth's is fairly circular--eccentricity is 0.0167). Which means that, at closest approach, Mars is about 206.65 million km from the sun, at farthest, 249.23 million km, average 227.94 million km. Earth at its closest is 147.17 million, farthest 152.03 million, average 149.6 million. I've probably put a few too many significant digits in those calculations.

What this means is that, on the average closest approach to the earth, Mars would be 78.3 million km from earth; its closest 54.6 million, its farthest close approach 102.1 million. This is using a 2-d approximation, which probably isn't all that far off. Deimos orbits Mars at about 23,000 km. At its closest, it is still 2000 times farther from Earth than from Mars.

Mars and Earth have been around a LONG time. It should be obvious that if anything disastrous were to occur due to proximity, it should have happened billions of years ago, or at least at the last close approach. As the other posters have indicated, nothing like that has happened.

I don't know if i want to talk about tidal effects--i guess i'll do so quickly. Mars will have perhaps three times the tidal influence on the Earth at its closest close approach as it does on the average close approach; these effects are still vanishingly small.

darkhunter
2003-Jun-08, 10:06 AM
Like could one of its moons fly into us or mess up our gravity? Stupid question, yes.

Methinks you should build a simple scale model of the solar system.

Some ideas on this page:
http://www.astrosociety.org/education/activities/handson.html
specifically, the toilet paper model in the last link.

Check this out... (http://www.umpi.maine.edu/info/nmms/solar/)

David Hall
2003-Jun-08, 01:41 PM
Methinks you should build a simple scale model of the solar system.

Better yet, try walking it (http://www.badastronomy.com/phpBB/viewtopic.php?t=1767).

tracer
2003-Jun-09, 08:17 PM
Mars is approching Earth in August if i'm not mistaken right? THe closest its been in years? Is it any threat to Earth, in any way, shape or form?
Only if the Martians choose that moment to attack.

ToSeek
2003-Jun-19, 07:47 PM
Here comes Mars! (http://science.nasa.gov/headlines/y2003/18jun_approachingmars.htm)

Nice graphic to show how much bigger it's going to get.

beskeptical
2003-Jun-20, 06:41 AM
Check this out... (http://www.umpi.maine.edu/info/nmms/solar/)

I want one.

There should be a solar system model in every town (that's big enough).

Pinemarten
2003-Jun-20, 09:38 AM
Refering to http://www.umpi.maine.edu/info/nmms/solar/

We should do a Canuck version and make the Texans jealous!
If we paint the Expo '86 ball yellow, I think Pluto would still be in Canada; or how about those huge natural gas storage balls? If we found one close to our extremes, no country could beat our record!
Stimulate unity/tourism/Astronomy etc?
My brain hurts; any fellow Canadians wish to help with the math/research/fundraising?

kucharek
2003-Jun-20, 10:00 AM
Mars is approching Earth in August if i'm not mistaken right? THe closest its been in years? Is it any threat to Earth, in any way, shape or form?
Only if the Martians choose that moment to attack.
From celestial mechanics, this would be the time where you need MOST energy to get from Mars to Earth, as, afetr escaping Mars' gravity, you would have to cancel all the orbital speed of Mars to go straight down to the sun to intercept Earth. And there you have to accelerate to Earth orbitl speed...
No wonder all the probes went now to Mars, and not in August.

Harald