The Southern Cross, or Crux to give it its official name, is the smallest of all the 88 constellations and an iconic feature of the antipodean sky. Yet it is not solely an asterism and navigation aid of the far south, as it can be seen from the Tropic of Cancer when best placed. Come and explore its wealth of interesting objects for binoculars and small telescopes.
An international team of scientists used the 64-metre Parkes Radio Telescope equipped with an innovative receiver to see through the stars and dust of the Milky Way, into a previously unexplored region of space. Hundreds of hidden nearby galaxies have therefore been studied for the first time, shedding light on a mysterious gravitational anomaly dubbed the Great Attractor.
A dwarf galaxy discovered close to the famous Sculptor Galaxy (NGC 253) by Australian astrophotographer Michael Sidonio has been studied in detail by the 8-metre Subaru Telescope in Hawaii. This fruitful collaboration between amateur and professional astronomers has revealed that the dwarf galaxy, now known as NGC 253-dw2, is being disrupted by the nearby giant spiral.
Every school child learns the basic structure of the Earth: a thin outer crust, a thick mantle, and a Mars-sized core. But is this structure universal? Will rocky exoplanets orbiting other stars have the same three layers? New research suggests that the answer is yes — they will have interiors very similar to Earth.
Planetary nebulae such as Hen 2-437 form when an ageing low-mass star — such as the Sun — reaches the final stages of life. The star swells to become a red giant, before casting off its gaseous outer layers into space. Hen 2-437 is a bipolar nebula — the material ejected by the dying star has streamed out into space to create the two icy blue lobes pictured here.
A new science satellite, the ASTRO-H X-ray Observatory, will blast into Earth orbit this month. The project, led by the Japan Aerospace Exploration Agency (JAXA), aims to collect a wealth of new data on everything from the formation of galaxy clusters to the warping of space and time around black holes. ASTRO-H boasts a sensitivity level that is orders of magnitude better than previous technology.
An international research team has used sophisticated computer simulations to calculate a two-dimensional map of the dust chemistry in the solar nebula, the thin dusty disc that surrounded the young Sun and out of which the planets formed. The study has given new insights into the chemical composition of the dust grains that formed in the solar system 4.5 billion years ago.
Stars are born inside a rotating cloud of interstellar gas and dust. Before finding itself on the star, however, most of the cloud lands onto a circumstellar disc forming around the star. The manner in which the material is transported through the disc onto the star, causing the star to grow in mass, has recently become a major research topic in astrophysics.
The nitrogen ice glaciers on Pluto appear to carry an intriguing cargo: numerous, isolated hills that may be fragments of water ice from Pluto’s surrounding uplands. Since water ice is less dense than nitrogen-dominated ice, scientists believe these water ice hills are floating in a sea of frozen nitrogen and move over time like icebergs in Earth’s Arctic Ocean.
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