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Exquisite measurements of the radiation left over from the big bang led us to believe that we could work out the curvature of the universe to within a few per cent. In doing so, we have determined how much energy the universe contains and that most of it is in an exotic form called dark energy, which is driving the expansion of space. However, recent discoveries have left me wondering if these claims were premature. As we learn more about dark energy and its effect on the expansion of space and time, we find that dark energy and the shape, or geometry, of the universe are worryingly intertwined.

People should not be afraid of dark energy. Remember that the problem with the cosmological constant isn't that it's mysterious and ill-motivated - it's that it's too small! The naive theoretical prediction is larger than what's required by observation by a factor of 10^120. That's a puzzle, no doubt, but setting it equal to zero doesn't make the puzzle go away - then it's smaller than the theoretical prediction by a factor of infinity.

A proposed experiment using ground-based telescopes, called BigBOSS, may be the most cost-effective way to study and measure the phenomenon called dark energy, which appears to be causing the universe to expand at an accelerating rate.

A new project to create a 3D map of space so large that scientists can find a 500 million-light-year-size remnant from the early universe inside it began operation last month. The Baryon Oscillation Spectroscopic Survey opened its eyes to the universe, taking in data from hundreds of galaxies and quasars in the constellation Aquarius, from its perch on the Apache Point Observatory in New Mexico. Eventually, it will image two million galaxies and quasars.

We got the same measurement no matter which method we used, finding out that 25-30% of the total energy of the Universe is in some type of matter. But, only about 0.5% of the total energy is in stars, which means that nearly all of this matter doesn't give off light! So what is the rest of this matter?

ATLAS is a particle physics experiment at the Large Hadron Collider at CERN. The ATLAS detector is searching for new discoveries in the head-on collisions of protons of extraordinarily high energy. ATLAS will learn about the basic forces that have shaped our Universe since the beginning of time and that will determine its fate. Among the possible unknowns are the origin of mass, extra dimensions of space, unification of fundamental forces, and evidence for dark matter candidates in the Universe.

Building on the legacy of the Sloan Digital Sky Survey (SDSS) and SDSS-II, the SDSS-III Collaboration is working to map the Milky Way, search for extrasolar planets, and solve the mystery of dark energy.

Using entire galaxies as lenses to look at other galaxies, researchers have a newly precise way to measure the size and age of the universe and how rapidly it is expanding, on a par with other techniques. The measurement determines a value for the Hubble constant, which indicates the size of the universe, and confirms the age of the universe as 13.75 billion years old, within 170 million years. The results also confirm the strength of dark energy, responsible for accelerating the expansion of the universe.