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Science with Integral – five years on   The red and green boxes represent dense objects discovered by Integral in our galaxy. The blue spots are supermassive black holes in the distant universe. The yellow spots are so-far unidentified sources of gamma-rays. Their distribution suggests that they are probably dense objects within the Milky Way. The atoms that make us  The centre of the galaxy shines brightly in gamma rays with a specific energy of 511 keV. This is the energy released during an encounter between an electron and its antimatter counterpart, the positron. It is not yet known what creates the antimatter particles.
The image shows the full sky at 511 keV. The densest objects in the universe  Integral, ESA's International Gamma-Ray Astrophysics Laboratory, is gathering some of the most energetic radiation that comes from space. The spacecraft was launched in October 2002 and is helping to solve some of the biggest mysteries in astronomy. Gamma rays are even more powerful than the X-rays used in medical examinations. Fortunately, Earth's atmosphere acts as a shield to protect us from this dangerous cosmic radiation. However this means that gamma rays from space can only be detected by satellites.
At time of launch, Integral was the most sensitive gamma-ray observatory ever put into space. It detects radiation from the most violent events far away and from processes that made the Universe habitable. Giant black holes  This all-sky map shows regions of ionized hydrogen gas in the local universe. The hidden black holes detected in the INTEGRAL survey of high-energy X-ray sources are located within the diamond-shape marks. Many sources were detected through the line of sight of the dusty Milky Way galactic plane, which is the bright area stretching across the center of the entire image from left to right.  ESA's Integral gamma-ray observatory has been observing Earth during a period spanning from 24 January to 9 February 2006. The main purpose of the observations has been to study the high-energy diffuse background radiation known as 'cosmic X-ray background' (CXB), by analysis of the decrease of its isotropic flux (not varying with distance or direction) while Earth passes in front of Integral's field of view. High-energy emission from the atmosphere, due to reflections of the CXB, interaction with cosmic rays and aurorae, have also been observed. Mysterious bursts  This artist's impression illustrates how a gamma-ray burst can flare dramatically over a short time period (gamma ray bursts usually last between a hundredth of a second to a hundred seconds). The bursts can occur as often as several times a day. There is no way to predict when or where they will next occur.
ESA missions such as XMM-Newton, Integral and Ulysses study these mysterious, powerful bursts. Release date: 20 February 2008 |