Where does the Gold come from?

Gold doesn’t come from your local jewelry store, and the Gold rush that occurred in the Yukon territory at the turn of the 20th century is not the source I’m talking about either.  I want to take it further back, to the origins of gold the element.  Similar to the origins of most other elements on the periodic table, it requires an immense amount of energy, such as the nuclear fusion that goes on within a star.  But Gold can not be made by a star’s thermonuclear engine.  Gold requires more energy, as does every other element heavier than Iron.  So...

Starship Fuel for the Future

For the first time in 30 years, the United States has the capability to produce fuel for deep space missions.  Plutonium-238 is an isotope that produces thermal energy through radioactive decay.  This energy can be converted into electricity and used to power spacecraft systems for decades of flight.  Systems using this isotope include the Viking landers, the Voyager spacecraft, and more recent missions like the Mars Science Laboratory (Curiosity) and New Horizons. The Oak Ridge National Laboratory in Tennessee, run by the US Department of Energy, has produced 50 grams of the isotope, amounting to the size of a golf...

What is between a Star and a Planet? Brown Dwarfs

Categorizing objects in the universe can be difficult.  The fiasco with Pluto over the last decade is more than proof of that.  We generally look to location and then to size as the two main methods for classifying the stuff that permeates the cosmos.  Galaxies contain stars, which host orbiting planets, which host orbiting moons; While asteroids fly in between planets and icy comets are wander through the outskirts of star systems. But what about the in-between objects? Often we find strange things in strange places. There are moons in our solar system that are larger than planets.  What would...