While we continue to unravel these mysteries, we are now looking to use gamma-ray bursts as a tool to study structures by using the light from GRBs that explode behind these structures as beacons. The mission we've proposed is called Xenia—from the Greek word for “hospitality”—and it's a very big collaboration. It's at least 50 institutions, with 90 team members from all over the world.
Xenia Video Presentation: Xenia will use GRBs as flashlights to take a look deep into space in areas where phenomena are too faint for us to see in any detail. The videos describes how Xenia will accomplish the mission and other science it will perform in between GRBs.
You, I, the air we breathe, the stars, and the other matter in the Universe are all composed of protons, neutrons, and electrons. These are the ingredients that make all elements from hydrogen to iron and beyond. Astronomers call elements heavier than hydrogen and helium “metals”. Metals are essential for star formation and their subsequent evolution, and ultimately the formation of planets and the development of life, as we know it. To understand the history and evolution of metals is an essential part for our understanding of the Universe.
Nature's most powerful explosions, gamma-ray bursts, tell us about the history of heavy metal production, when the first stars formed long after the Big Bang. The earliest stars to be born were more massive than any that we know of today and had low metal content. Because of their high mass, these stars exhausted their fuel supply in about one million years and perished in enormous supernovae that ejected the first 26 elements (up to iron) in the Periodic Table. Successive generations of stars then formed out of clouds of dust that were enriched by metals ejected by supernovae. As these massive, metal-rich stars exploded, they created new elements. Every element heavier than iron was produced in a supernova, including gold.
Using X-ray imaging and spectroscopy, Xenia will read the metal diaries of the Universe to explore and reconstruct their cosmic history from the first population of stars to the processes involved in the formation of galaxies and galaxy clusters. GRBs are like beacons to an ancient world because they allow us to see at great distances the light from old stars, and their brightness gives us the opportunity to use spectroscopy to measure the chemical abundances in early stars and galaxies.