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Earth's Little Brother Found
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One man's constant is another man's variable. -- A.J. Perlis
One man's constant is another man's variable. -- A.J. Perlis
Second Moon (Score:0, Interesting)
Uh, wouldn't that screw up the tidal system?
Interesting idea, though.
Not quite a planet, eh? (Score:0, Interesting)
Of course, the part I don't get, *why* can't it hit the Earth? In roughly the same orbit around the sun, a much smaller mass has to travel MUCH slower than the Earth to maintain that orbit. So okay, I suppose *we* should hit *it*, rather than the other way around, but still...
Earth's second moon (Score:5, Interesting)
600 years? (Score:5, Interesting)
If, in 600 years, we haven't sent astronauts to visit other planets, I have preemptively lost faith in the human race.
Come on, in 600 years we should have a pretty decent Mars colony going.
Re:Not quite a planet, eh? (Score:5, Interesting)
No, any object in the same orbital path travels the same velocity.
Think about it this way. If I have a heavy object and a light object orbiting at Earth's distance from the sun, by your hypothesis one will travel faster than the other. So if I duct-tape them together they should travel at a speed somewhere in-between the fast one and the slow one. But the taped-together object masses the sum of both smaller objects so it should travel faster. It can't travel both faster than and slower than its larger half, so the hypothesis can't be right.
Orbits, nodes, & more (Score:2, Interesting)
Whether this new planet is actually a satellite of Earth is still to be determined. Also, a similar orbit does not mean that the climate is also known to be similar a priori.
The Earth's ecliptic orbit in summation with the Moon's orbit around the Earth means that the Moon must intersect the ecliptic; in fact, it will have to do so at two distinct points.
Has anyone found these nodal points for "Earth's Little Brother" yet? That's the true test of whether or not we will truly be affected by such circumstances.
Re:Not quite a planet, eh? (Score:3, Interesting)
Imagine you have a cannon. You fire a cannonball out of it, and it follows a parabolic path until it hits the ground (Boom). Now, you get a more powerful cannon, and fire a cannonball even farther. In fact it's so powerful that the cannonball is traveling so fast horizontally that the ground is receding from it, due to the curvature of the Earth, faster than gravity is pulling it down to the Earth!
Tada! So the cannonball just keeps moving, around the Earth. It's in orbit.
I hope that explanation helps at least one person who was like me.
Zookeeper Hypothesis (Score:5, Interesting)
One proposed resolution [space.com] is the Zookeeper Hypothesis, ie, they could have contacted us but are just waiting and watching for us to evolve, a la 2001.
If so, then wouldn't they want to put a probe near the Earth, which swoops down every few centuries or so for a close look, to see if any thing interesting has happened?
Re:Earth's second moon (Score:3, Interesting)
Interplanetary probes use this method all the time for escaping earth's gravity. After launch, they orbit the earth for awhile building up momentum (this is known as a 'gravity assist') then fling themselves out.
This is actually a much more common cosmic event than actually capturing something in permanent orbit. Doing that requires careful placement in the case of artificial satellites or just random chance in the case of natural ones.
Mr. Bass's Planetoid! (Score:3, Interesting)
She wrote "The Wonderful Flight to the Mushroom Planet", but in "Mr. Bass's Planetoid", she created a tiny asteroid that allowed the two young protagonists to view the Earth while having landed their spaceship on this asteroid.
Next thing you know, the BBC will report that we've discovered Lepton! Watch out Mushroom People, we're coming!
a real answer to Fermi (Score:4, Interesting)
Confused... (Score:5, Interesting)
How is this object considered a "companion" while Cruithne - Earth's "second moon" - is not?
Earth's Second Moon [slashdot.org]
2nd Moon Orbiting Earth Discovered [slashdot.org]
Google Search: Cruithne [google.com]
Is there an astronomer in the house? Or anybody who could clarify this?
Re:meters, miles... (Score:2, Interesting)
No... Four. A nautical mile is 6000 feet; a knot is one nautical mile/hour. A statute mile is ~ 5200 feet. Oh, wait - the wind direction is specified using a 360 degree circle, when it could also be expressed in radians, so really, that's five distinct measuring systems.
Re:meters, miles... (Score:2, Interesting)
Move to the southern hemisphere. You're now the other-side-up, and left and right are reversed.
This is now wandering off-topic even further, but: Have you every tried to define "left"? Pretend you're on the phone with aliens, who want to know what we define as "left".
Up, down are easy -- gravity based definitions are fine. But then try to describe clockwise, or right.
I come close when I have the alien move an electron in the "up" direction, and then try to define clockwise in terms of the direction of the magnetic field lines created.
But then you need a way to define the polarity of the magnetic field -- and I can't think of a naturally occuring magnetic dipole to compare it to.
Nasty brain twister, if you let yourself be kept up at night thinking about such things.
- Peter
Re:Effect on Earth (Score:4, Interesting)
I'm a firm believer in astrology, and I think that this type of object might play some role. [...] Thought?
Apparently not on your end of the connection, there's not. Now, I know we're supposed to be respectful of everyone's beliefs, no matter how crackpot or unfounded they may be, but come on! The URL is "science.slashdot.org," not "stuff-not-subject-to-empirical-proof,reason,or-ex perimentation.slashdot.org". This is a discussion about an asteroid in companion orbit (apparently of the L4 and L5 LaGrange points; see above), and you're wondering what effect it would have if 2002 AA29 were in the fifth house while Jupiter and Venus are in ascendance.
In the immortal words of "Weird" Al Yankovic, "Now, you may find it inconceivable or at the least a bit unlikely that the relative positions of the planets and the stars could have some special deep significance that applies exclusively to only you." I do. 2002 AA29 has been conclusively proven to exist. Has the "like, influence of the planets, man" been subjected to the same rigorous standards?
Didn't think so. Thank you, please drive through.
Re:meters, miles... (Score:3, Interesting)
There is a series of Discovery channel involving building a light aircraft, one of the first points the presenter made was that the construction involved using strange mixtures of units.
You also have fuel load on commercial aircraft being measured as a weight, thousands of pounds; whilst dispensed as a volume; either litres, US gallons or imperial gallons depending where the plane fills up. Messing up the cacluations leading to a flight crew having to test the gliding abilities of an airliner over Canada.
I really wish us stubborn americans would just switch to SI...
The US signed the "Treaty of the metre" a long time ago, the US Congress explicitally has the power to set weights and measures so it's really a political problem.
Re:Confused... (Score:3, Interesting)
See Weigert [queensu.ca] for more information.
Re:Why the US will never switch to metric (Score:2, Interesting)
Example: Freezing to Boiling on water is 32F to 212 F and 0 C to 100 C or 273 K to 373 K. Therefore, by simple math, there are 180 degrees F between the boiling and freezing of water, and only 100 degrees C or K for the same measurements. It would seem to me that the finer temperature scale is degrees F.
Re:meters, miles... (Score:3, Interesting)
This was the Gimli Glider [cadetworld.com], which didn't crash, but did run out of fuel and had to make a dead stick landing on the abandoned RCAFB Gimli. No-one was seriously hurt. The aircraft, registration C-GAUN, serial number 22520, is still in service after $1M worth of repairs. Here [airliners.net] are some photos from earlier this year.
Re:Why the US will never switch to metric (Score:2, Interesting)
(To this post's grandparent) BTW, have you ever watched a weather report? They give temperatures in ranges (ie High 60's). With Celcius, the ranges will be tighter (ie 16C-17C), so I still don't understand your point.
Re:meters, miles... (Score:3, Interesting)
Twenty something years after New Zealand changed to metric I find it interesting and a little disappointing sometimes to observe the results.
Degrees F quickly disappeared because (I assume) of TV weather forecasts. MPH has gone because of car speedos but I think you would get blank looks if you asked a mechanic or tyre installer about pressure in Kpa.
Pounds and ounces seem to be long forgotten except for babies' weights.
Commercial floor space still seems to be advertised in sq ft, land area often in acres although I'm sure the official documentation is metric.
Off the cuff comments on TV by police etc at the scene of some event will often make it clear that feet and yards are still more comfortable than meters.
New born babies' weights are more often than not quoted in the newspapers in pounds.
Some adults still quote weight in stones (14 pounds?) although I doubt that you can even buy scales with stones now.