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Mars Swings Unusually Close to Earth
amazon10x writes "Mars will come unusually close to the Earth on Saturday; the second time in 60,000 years. The last occurrence was in 2003. 'This is the best we're going to see Mars, so we should strike the iron while it is hot,' said Kelly Beatty, executive editor of Sky & Telescope magazine. The Red Planet will be 43.1 million miles from Earth at 11:25pm [Eastern time]." Update by J : Starting a few hours after sunset, look fairly high in the eastern sky.
Well what time zone? 11:25pm here could be 6:25am somewhere else. Bad slashdot!
"Unusual" can also mean "rare"-I think that's the context it's used in here.
To fight the war on terror, stop being afraid.
For those like me wondering the time zone, I actually RTFA:
On Saturday, Mars' orbit will bring it 43.1 million miles away from Earth, with its closest pass scheduled for 11:25 p.m. EDT.
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Second time in 60,000 years that we know of? If the last time it happened was in 2003, and this is only 2 years later, and the next time is "scheduled to be in 2018 (FTFA)", is it possible we just didn't have the technology to detect it back then?
The information in the article in SI units:
> On Saturday, Mars' orbit will bring it 69.4 million kilometers away from Earth, with its closest pass scheduled for 3:25 p.m. UTC.
*sigh* The configuration that allows it get this close happens every 60,000 years. The cycle takes a few decade to play out.
"Software is too expensive to build cheaply"
With all the natural disasters lately, I'm stocking up on food and water in case it hits.
How about twice in 2 years, while having not occurred until 60,000 years before that?
...and they want their geocentric theory back...
From TFA: The two planets -- normally separated by about 140 million miles -- will not be this close again until 2018.
Normally separated by 140 million miles? On average, Earth orbits at 93m miles, Mars at 140m miles, both roughly on the same plane. That means the distance will vary periodically from around 230m miles to 47m miles. This current phenomenon is a "minimum minimum" which is why it is notable.
It sounds like CNN looked up the orbital distance from Mars and assumed that it orbits the Earth...
Ydco co
*Doesn't something like this happen every year these days?*
If by "every year" you mean "Every other year," and by "every other year" you mean "2003" then yes, it happens every year. Note, please, that every other year (give or take) Mars gets closer to us, then further, then closer, so there are times where it will be closer than others. This one (and the one in 2003) are just extra-close.
*So it came unusually close in 2003... and now again in 2005... and they're expecting it again in 2018?*
They're not "expecting" it so much as "knowing" it, but yes, Mars gets closest to us every couple years, and sometimes it's closer than others, so it will be in 2018 as well (I assume, I haven't actually researched 2018 in particular). It won't be as close as it is this year, or in 2003, which made these two so special.
*And so it's happening 3 times in 15 years... but we're going to blow that up to say "3 times in 60,000 years!!!"*
We're not blowing up anything. 60,000 years ago (or so) Mars was as close to the Earth as it will be this week. Between 60,000 years ago and now, it's only happened once, in 2003, and it will happen again in a couple days.
*Honestly... the New Orleans Saints win playoff games more rarely than this occurs.*
To put this in terms you'll understand, think of it this way. The NOS win a game, after losing, say, 5 in a row. The announcer says "This is their first win in 6 games." Are you going to complain and say "No it's not, it's their first win in ONE GAME!"?
*Other than it's significance to NASA's mars mission and palmists, all this means to john-everyman is that the red dot in the sky is a little brighter.*
Which is why we're having this discussion on a geek website. It's NEWS.
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Given advances in technology by that point, it should make a great time to put men on Mars.
How long will we have to wait intil we're advanced enough to put women there as well?
"I've got more toys than Teruhisa Kitahara."
We all went to school and we all know how this works. Let's just calm down and consider how rare or not rare this event is.
Earth orbits the sun in a nearly circular orbit at a mean distance of 1 astronomical unit (by definition of AU). Mars on the other hand orbits the sun in a less circular orbit that takes it as far as 1.67 and as close as 1.38 astronomical units from the sun. As we all know, it takes earth 1 year to orbit the sun (again, by definition of a year). It takes Mars 687 days (1.88 earth years).
Let's put this into more "human" terms using an analogy. Let's imagine a rock in the middle of a field. And let's put two people walking in circles around the rock. One person at a distance of 10 meters and the other at a distance that varies between 14 and 17 meters from the rock. Very quickly we'll notice that the closest the people can ever come from eachother is 4 meters and the furthest they can come is 27 meters. But we also notice that as they walk around, the person closer to the rock will take 1 minute to walk around the rock and the person on the outside will take 1.88 mintues so the one on the inside will be overtaking the one on the outside roughly every other minute (once per two years in Mars-Earth terms). And whenever they overtake, the distance will be anything from 4 to 7 meters. And quite often, it will be a distance of 4 to 5 meters or so. It's not rare at all. What's rare is that it would be VERY close to the minimum 4 meters.
So.. when we say it's "amazingly close" and "closer than in 60000 years", it's more like getting within 4.1 meters instead of 4.25 in the analogy above. We're not talking about 4 meters vs. 27 meters or anything like that.
Conclusion: this isn't THAT special at all. Mars isn't THAT much closer at all. For example for Mars missions and such, the difference in distance is mostly irrelevant.
Peppe
I don't know what speeds exactly rockets travel at, but at Mach 2 (earth relativistic since there's not air in space, but about 1200-1400MPH give or take depending on altitude)
Even a relative slow moving spacecraft travels far, far faster than the speed of sound. The average interstellar spacecraft generally cruises at somewhere around the neighborhood of 50,000 mph - roughly Mach 66. Some have been known to hit much higher speeds, but usually that's a result of a nearby planet's gravitational pull.
According to the Guiness Book of World Records, the fastest recorded spacecraft were the NASA-German Helios probes, which hit 158,000 mph during their slingshot pass around the sun.
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This makes virtually no difference to the effort required to transfer an object to Mars from Earth. The orbit would be an elliptical transfer orbit (the most efficient), and is far more dependent on the position of Mars relative to Earth (hence "launch windows" for probes).
The 7ish million miles will make naff all difference - the point is actually when someone will stump up the cash, and when we figure out how to have an effective life support system (food, water, oxygen, shielding against radiation, etc, etc). The furthest humans have gone is ~250,000 miles - 43 and more million miles is, ahem, miles further.
This is just so the demons can use those teleport pads to beam themselves to Earth. Here's hoping that by the time they arrive, we've figured out how to hold a flashlight AND a gun!
"Reality is merely an illusion, albeit a very persistent one " -Albert Einstein
Exactly. And even more importantly for Mars missions and such is that the energy / velocity required to get to Mars varies hardly at all between the every couple of year distance of 49 million miles vs. this year's 43.1 million miles. It's easier to visualize if one understands that one doesn't fly in a straight line to Mars from Earth. That is, to fly from Earth to Mars today, you wouldn't travel 43.1 million miles just because that's the distance today. Rather, you'd travel something like 500 million miles cause you'd fly in a so called Hohman transfer orbit that essentially traces an elliptical orbit that has a periapsis (closest to sun) point that touches Earth's orbit and apoapsis (furthest from the sun point that touches Mars' orbit. The distance of the arc of that orbit between the periapsis and apoapsis is very roughly 500 million miles and varies VERY little depending on how close Mars was to Earth at launch time. And equally small is the variation in flight time and required fuel, thrust and delta velocity.
Peppe
but what about getting them back?
Who says it has to be a return mission? Come on, don't you think there would be plenty of qualified volunteers for a one way mission? This is why I think China will be space pioneers (well, 2nd generation pioneers) - because they will be able to launch one way missions without too many naysayers complaining about it.
And the worst thing about this whole thing is that it isn't true!
While in 2003 Mars passed us closer then at any other time in the last 60.000 years, it passes us by pretty close every 15 and 17 years. The 2003 passage was a "whopping" 1% closer to us than the 1971 pass, and this year's pass at 43 million miles is not unusual at all, every 15-17 years there's at least one pass that is significantly closer than that, the 1988 pass being at 37 million miles - noticably further than 2003, but much closer than this year's passage.
So as usual, take main stream press accounts of science stuff with a very big grain of salt!
Couldn't be much more from the heart.
--
WHO ATE MY BREAKFAST PANTS?
Imagine an egg still in its shell. Looking down at the egg, it's like the shell is the orbit of Mars and the yolk (still inside the shell, of course) is the orbit of the Earth. In 2003, when the two planets got as close as they can get, it was like both were on the wide end of the egg, where the yolk is closest to the shell. Well, Mars' orbit takes about two years and two months to complete, so this year Mars and the Earth meet up near the wide end of the egg again. In two years' time, though, Mars will be a little further along the shell of the egg when it catches up to Earth, which will be a little further from the wide end of the egg.
In 60,000 years or so, the closest approach will have walked all the way around the edge of the egg until it's at the "closest closest approach," the wide end of the egg. There's nothing unusual about it.
We can't very well send both men and women since they wouldn't be able to control themselves. :)
An it will continue to pass closer and closer until *SPLAT*.
Haven't you noticed? 5 years ago, it would have been rare to meet 2 dense induhviduals in a week! Now, I usually encounter at least 1 a day. This accumulating density is subtly increasing the Earth's gravitational field. (Yes, yhat's also why your scale keeps going up.)
I believe reality television is to blame. I eagerly tuned in to the first season of Survivor, thinking "Oh boy! Televised Darwin Awards!" But, wha?? They *vote* people off? The smart people? This isn't "survival of the fittest", it's survival of the weaseliest. (It is so a word, Dilbert says so and that's good enough for me!)
And weaselness is closly related to denseness. Don't believe me? Take a minute to talk to your upper management. Then another minute to see what they get away with. See!?
They use this new sort of witchcraft called 'math,' along with arcane properties such as trajectory, velocity, etc.
In addition, the article states that Earth and Mars are usually 140 million miles apart, as if they just stay stationary and only occasionally move closer. 140 million may be the average, but the separation is always changing. Seriously, this is why other countries laugh at the US, because even our science writers lack even a grade-school education in science.
I am so tired of this story. Every 22 months it comes back and I have to explain it to all the non-technical members of my extended family who ask me about it, expecting a freaking flash in the sky or a moon sized UFO or some crazy crap like that.
...
Think about this: all of these people are voters. Now extrapolate to environemental policies, energy issues, stem cell research
Freedom is on the march!
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