Welcome to the first posting at ORBITAL MANEUVERS new blog site!

I will be moving the posts from the old site shortly, but until then the original site is still available.  This move will allow more flexibility in the blog posts.  Now on to the good stuff!

Black as Coal

In the novel, ORBITAL MANEUVERS, the asteroid that impacts Earth escaped detection for of a number of reasons, but one of the main reasons is that it was composed of a material that was blacker than black — it reflected almost no light.  How black is that?

The scientific term used to quantify this blackness is albedo.  It is simply the ratio of the amount of incident light on an object to the amount of light reflected back.  For the Moon, it is on average about 12%.  Think about that the next night you are out and the full moon is shining above.  Only 12% of the light from the Sun reflects off the surface of the Moon.  Imagine what it would be like if it was 50% or higher!  Also, for another twist on this, consider that the average albedo of a paved, blacktop road surface is about 10%.  So, that bright orb in the night sky really isn’t any brighter than the road you may be driving or walking on!

Now let’s take a look at this new planet that was discovered by Kepler, TrES-2b, about 750 light-years distant in the constellation of Draco the Dragon.  Although this planet is extremely hot, about 1,800 degrees Fahrenheit (980 degrees Celsius, it is extremely dark, with an albedo of slightly less than 1%.  Coal has an albedo of about 1%, which is a something most people can relate to and it’s pretty dark, but we’ve found asteroids in our Solar System that have an albedo of about .6%.  On the other end of the spectrum we have Saturn’s icy moon Enceladus, which has an albedo of 99%.

Artist's impression of TrES-2b - Image courtesy of David A. Aguilar (CfA) Harvard Smithsonian Center for Astrophysics

So, it’s not beyond the realm of possibility that the asteroid that impacts Earth in the novel is so dark that the surveillance systems in place at the time could have missed it.  It’s nice to know that we are more active today as far as monitoring asteroids in the Solar System than we were ten years ago when the novel was started.

What is TrES-2b made of?  We don’t know.  Add that to the list of things we need to learn about in this vast Universe we live in.  The wonders never cease!

Till next time,

RC Davison