Institute of Astronomy

Astronomy News

Pluto snapped from 8 million km

10 July 2015 - 9:33am

Nasa's spacecraft New Horizons acquires another stunning view of Pluto as it bears down on the dwarf planet, ahead of its 14 July flyby.

What will Pluto mission discover?

10 July 2015 - 9:33am

The key questions about Nasa's Pluto flyby

Biggest Explosions in the Universe Powered by Strongest Magnets

9 July 2015 - 10:04am
Observations from ESO’s La Silla and Paranal Observatories in Chile have for the first time demonstrated a link between a very long-lasting burst of gamma rays and an unusually bright supernova explosion. The results show that the supernova was not driven by radioactive decay, as expected, but was instead powered by the decaying super-strong magnetic fields around an exotic object called a magnetar. The results will appear in the journal Nature on 9 July 2015.

Mystery plasma blobs lurk in deep space and no one knows why

9 July 2015 - 10:02am

Dark objects affecting the radio signals from quasars and pulsars could be strangely dense blobs of plasma. But if so, how did they get there?

It's time to decide when to declare a planet lifeless

9 July 2015 - 10:01am

Spacecraft are sterilised before they visit Mars to protect any life there – but it is expensive and no life has yet been found. When do we stop?

A very luminous magnetar-powered supernova associated with an ultra-long γ-ray burst

9 July 2015 - 10:00am

A very luminous magnetar-powered supernova associated with an ultra-long γ-ray burst

Nature 523, 7559 (2015). doi:10.1038/nature14579

Authors: Jochen Greiner, Paolo A. Mazzali, D. Alexander Kann, Thomas Krühler, Elena Pian, Simon Prentice, Felipe Olivares E., Andrea Rossi, Sylvio Klose, Stefan Taubenberger, Fabian Knust, Paulo M. J. Afonso, Chris Ashall, Jan Bolmer, Corentin Delvaux, Roland Diehl, Jonathan Elliott, Robert Filgas, Johan P. U. Fynbo, John F. Graham, Ana Nicuesa Guelbenzu, Shiho Kobayashi, Giorgos Leloudas, Sandra Savaglio, Patricia Schady, Sebastian Schmidl, Tassilo Schweyer, Vladimir Sudilovsky, Mohit Tanga, Adria C. Updike, Hendrik van Eerten & Karla Varela

A new class of ultra-long-duration (more than 10,000 seconds) γ-ray bursts has recently been suggested. They may originate in the explosion of stars with much larger radii than those producing normal long-duration γ-ray bursts or in the tidal disruption of a star. No clear supernova has yet been associated with an ultra-long-duration γ-ray burst. Here we report that a supernova (SN 2011kl) was associated with the ultra-long-duration γ-ray burst GRB 111209A, at a redshift z of 0.677. This supernova is more than three times more luminous than type Ic supernovae associated with long-duration γ-ray bursts, and its spectrum is distinctly different. The slope of the continuum resembles those of super-luminous supernovae, but extends further down into the rest-frame ultraviolet implying a low metal content. The light curve evolves much more rapidly than those of super-luminous supernovae. This combination of high luminosity and low metal-line opacity cannot be reconciled with typical type Ic supernovae, but can be reproduced by a model where extra energy is injected by a strongly magnetized neutron star (a magnetar), which has also been proposed as the explanation for super-luminous supernovae.

Feedback in low-mass galaxies in the early Universe

9 July 2015 - 9:59am

Feedback in low-mass galaxies in the early Universe

Nature 523, 7559 (2015). doi:10.1038/nature14454

Authors: Dawn K. Erb

The formation, evolution and death of massive stars release large quantities of energy and momentum into the gas surrounding the sites of star formation. This process, generically termed ‘feedback’, inhibits further star formation either by removing gas from the galaxy, or by heating it to temperatures that are too high to form new stars. Observations reveal feedback in the form of galactic-scale outflows of gas in galaxies with high rates of star formation, especially in the early Universe. Feedback in faint, low-mass galaxies probably facilitated the escape of ionizing radiation from galaxies when the Universe was about 500 million years old, so that the hydrogen between galaxies changed from neutral to ionized—the last major phase transition in the Universe.

Astrophysics: A twist in the tale of γ-ray bursts

9 July 2015 - 9:59am

Astrophysics: A twist in the tale of γ-ray bursts

Nature 523, 7559 (2015). doi:10.1038/523164b

Authors: Stephen J. Smartt

An unusually long burst of γ-rays zapped Earth in December 2011, lasting 4 hours. The cause of this burst is now proposed to be a peculiar supernova produced by a spinning magnetic neutron star. See Letter p.189

Pluto fly-by: a graphical guide to the historic mission

9 July 2015 - 9:56am

Pluto fly-by: a graphical guide to the historic mission

Nature 523, 7559 (2015).

Author: Alexandra Witze

New Horizons mission is set to speed past an ice world at the fringes of the Solar System.

Astronomy: Event pile-up may explain solar storm

9 July 2015 - 9:54am

Astronomy: Event pile-up may explain solar storm

Nature 523, 7559 (2015). doi:10.1038/523131b

A rare combination of factors might have combined to make a solar storm in March 2015 the strongest seen for a decade.Like most such storms, this one began when the Sun spurted fast-moving plasma in an event called a coronal mass ejection. A different

Rare system of five stars discovered

9 July 2015 - 9:34am

Astronomers have discovered a very rare system of five connected stars.

Pluto map shows 'whale' of a feature

9 July 2015 - 9:33am

Scientists release their latest map of the surface of Pluto, using images from the inbound New Horizons probe.

Astronomers use cosmic gravity to create a 'black-hole-scope'

7 July 2015 - 9:43am

The INTEGRAL, Fermi and Swift space observatories have used the magnifying power of a cosmic lens to explore the inner regions of a supermassive black hole.

New Horizons hiccup won't affect Pluto mission science

7 July 2015 - 9:41am

NASA says temporary loss of contact with the spacecraft over the weekend was a one-off and won't affect its historic arrival at the dwarf planet next week

Pluto probe 'on course' for flyby

7 July 2015 - 9:23am

The New Horizons spacecraft lost very little science data when it went into "safe mode" at the weekend, the mission team says.

Counting stars with Gaia

6 July 2015 - 9:45am

This image, based on housekeeping data from ESA's Gaia satellite, is no ordinary depiction of the heavens. While the image portrays the outline of our Galaxy, the Milky Way, and of its neighbouring Magellanic Clouds, it was obtained in a rather unusual way.