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Found this...

http://www.mira.org/fts0/planets/101/text/txt201x. htm

It is gravitation that tends to cause the spin to slow down. The moon is locked into a 1:1 ratio of rotation:revolution, so it always presents the same "side" to the earth (no, not the "dark side of the moon v. light side of the moon bit. Even when the moon is a waning crescent, it is presenting the same surface features towards the Earth).

What will be interesting for Earth is to see which of the two largest bodies in terms of gravitation wins out, or if there will always be some form of resonance. Will we always present the same portion of Earth to the sun, so that one side of the planet bakes while the other freezes (which I believe is where Mercury is headed. Try going here: http://www.mira.org/fts0/planets/092/text/txt001x. htm for a description of Mercury's rotational period), or will we always present the same surface to the moon while we orbit the sun?

Actually, if I remember correctly, Mars has it's problems not because of it's size or mass, but because it has a weak magnetic field. Because of that, every solar storm that smacks into the planet shears off some of it's atmosphere. Linky.

Saturn's moon Titan has a radius of about 2570km and a mass of about 1.35e23kg and has a thick atmosphere. Linky

Mars's radius is about 3397km and has a mass of about 6.42e23kg and has a thin atmosphere.Linky

mars polar caps are dry ice (frozen CO2) http://www.mira.org/fts0/planets/097/text/txt003x. htm

Alright, even though earlier in the article other forces are named as the main actors on Oort Cloud comets. I read the part that you quote as "once the comet is nudged towards the sun, the bigger planets can then influence the orbits so they become shorter".

Why do I still doubt it? Jupiter mass is only 0.001 solar mass, Oort cloud distance is in the order of magnitude of 100,000 AU, gravity influence decreases with distance squared, and comets are small.

But hey, the Oort Cloud has not even been proven to exist so why are we bickering? :)

In all the APOD picture of Saturn I found a reference to Spokes and a picture that contains them.

<sarcasm>

The sun is angry; we are doomed. These flares are just the beginning, they will increase in magnitude until they are so big, they penetrate the Earth's magnetic field, destroy the entire ozone layer and sanitize the surface of the Earth with UV rays - just like an autoclave. Not even bacteria will survive except underground and deep in the Ocean.

The signs are showing, this is the END OF THE WORLD! The sun has been showing more activity since 1940 than it has for the last 1000 years put together. Doom is imminent!

Scientists don't act worried, they think they understand the sun and how it works, but science it just guesses. Maybe the sun is made of iron instead of hydrogen where would all the theories that say we are safe be then, if such a basic 'fact' about the sun turned out to be wrong?

As the flares grow in size and number you will all see that my theory is correct! "What is my theory?" you ask. It is that since the END OF THE WORLD makes a good movie plot point, that it must be happening NOW! These are going to be interesting times... We should all start storing canned food and porno mags in bomb shelters now before it's too late and we get cooked by the MASSIVE RADIATION STORM!

And what if the sun should stop flaring, and I should get proven wrong. WE ARE STILL DOOMED! In the same way that load from a light socket makes the generators in a power plant harder to turn, so geomagnetic storms transfer the kinetic energy of megatons of speeding charged particles directly to the magmatic dynamo at our planet's core. Small purturbations can affect this chaotic fluid flow in unpredictable ways but the most worrying is that the shock from the kinetic energy of all those particles will cause avalanches at the core/mantle boundary this will cause massive vulcanism that will cover the earth with lava!

If that doesn't get us, terrorists wielding viruses will.

Get out your sandwich board and whisky! Walk the streets and warn! THE END OF THE WORLD IS NIGH!!!!

<sarcasm>

John Mitchel, in 1783, had the idea that a star could be so heavy that the light itself could not escape its gravitational field. I think this precludes mr. Poe by some decades.

I assume that the gravity lensing difference between the two stars can easily be picked out because although they both throw a lot of light, they don't have the same spectrum, and probably not even the same redshift. You can then subtract out the closer star because you very carefully observed it when there was nothing significant behind it.

This is not gravitational lensing, but gravitational microlensing. From the BBC text I guess it's the planet's gravitational field modifying the star's light curve. The light curve is a plot of light intensity vs time. For a main sequence star, i.e., a "regular" one, say, Sol, there's no reason for the light curve to change over a small period of time (400 days or less, typical in microlensing events). Now, what puzzles me is an Earth sized planet's gravitational field isn't strong enough for the effect to be measurable.

You can look here and here if you are interested in more information about gravitational lenses. I couldn't find more details at Mount Stromlo Observatory's homepage.