What is the universe made of? This question has driven astronomers for hundreds of years. For the past quarter of a century, scientists have believed “normal” stuff like atoms and molecules that make up you, me, Earth, and nearly everything we can see only accounts for 5% of the universe. Another 25% is “dark matter”, an unknown substance we can’t see but which we can detect through how it affects normal matter via gravity. The remaining 70% of the cosmos is made of “dark energy”.
Discovered in 1998, this is an unknown form of energy believed to be making the universe expand at an ever-increasing rate. In a new study soon to be published in the Astronomical Journal, we have measured the properties of dark energy in more detail than ever before. Our results show it may be a hypothetical vacuum energy first proposed by Einstein – or it may be something stranger and more complicated that changes over time