What does it mean?

XMM-Newton – is a joint European Space Agency (ESA)-NASA orbiting observatory, designed to observe high-energy X-rays emitted from exotic astronomical objects such as pulsars, black holes and active galaxies. It was launched on December 10, 1999 from the ESA base at Kourou, French Guiana and continues to make observations today.

X-ray – high energy electromagnetic radiation that is more powerful than visible and ultra-violet light but less than gamma-rays. Because of their high energies and short wavelengths, x-rays can easily pass through “soft” materials and can be used to take pictures of insides of things, like the human body.

Dark energy – a hypothesized exotic form of energy that makes up the majority of the universe. This form of energy is causing the expansion of the universe to accelerate.

Is that all?

XMM-Newton – The main ESA website for XMM-Newton.

XMM-Newton Guest Observer Facility (GOF) – The GOF provides a clearing house for project-generated technical information and analysis software as well as user and proposal support on the U.S. side of the Atlantic.

X-rays – Detailed information about X-rays and their uses for astronomy as well as here on Earth.

Discovery of the most massive cluster of galaxies known in the distant Universe – XMM-Newton press release.

What is Dark Energy? – Intended for students age 14 and up and other interested in finding out more about dark energy.

Isaac Newton’s Life – Biography of Sir Isaac Newton.