Bad Astronomy

Welcome from the DarkSyde

The political blog DailyKos has a weekly science section written by a man known only as DarkSyde (though leads to his identity aren’t all that difficult to turn up). This week’s post is interesting: he put up a very pretty illustration by artist Karen Wehrstein of what the sky might look like from Gliese 581c, the planet recently discovered that is slightly larger and more massive than the Earth.

To my delight, he makes it clear this is pure speculation based on the little we know about the planet, but there is enough in the image to spark the imagination (I’ll note that he and I corresponded a few times over what should be in the picture). Red dwarfs are notoriously active stars, with magnetic fields that drive flaring activity on the surface and corresponding starspots. However, they are not flattened– that’s an atmospheric effect, just like how the Sun and Moon look flattened when on the Earth’s horizon.

Adding that was my idea. :-)

At the distance of the planet from its star, the red dwarf would be bigger in apparent size than the Sun is in our skies, and the total brightness would be higher. However, the surface brightness would be lower – the amount of light you see from the star per square degree. Hanging low on the horizon, with the Moon Illusion in full force, the star would look positively enormous, glowering, and surface features would be easier to spot. It would be very dramatic, and incredibly beautiful.

Ms. Wehrstein has some more artwork of the night side as well, speculating on how things might look there too. Some folks might protest this sort of thing; letting our imagination run ahead of our science. In fact, I support this. As long as people understand it is speculation and not necessarily reality, this lets us visualize these alien vistas and maybe spur us on to think more about what circumstances really are like in such places. Who knows who will be inspired by such artwork, then go on and study the real thing?