Institute of Astronomy

Astronomy News

Japan Launches Asteroid Mission

5 December 2014 - 1:37am
On Dec. 3, the Japan Aerospace Exploration Agency successfully launched its Hayabusa2 mission to rendezvous with an asteroid, land a small probe plus three mini rovers on its surface, and then return samples to Earth. NASA and JAXA are cooperating on the science of the mission.

Autumn Statement: response from the Royal Astronomical Society The RAS comments...

4 December 2014 - 3:06pm
Autumn Statement: response from the Royal Astronomical Society

The RAS comments on the UK government's latest economic policy.

Autumn Statement: response from the Royal Astronomical Society
The UK Government yesterday published its Autumn Statement, which sets out public sector spending plans and expected economic performance. In science, new announcements included an additional commitment of £55m for the European Space Agency, to suppo

Know thy enemy: the million space rocks we must find

4 December 2014 - 1:41pm
It's time to ramp up efforts to find the many smaller near-Earth objects that could unleash destruction on our planet, says astronomer Martin Rees

Green Light for E-ELT Construction

4 December 2014 - 11:00am
At a recent meeting ESO’s main governing body, the Council, gave the green light [1] for the construction of the European Extremely Large Telescope (E-ELT) in two phases. Spending of around one billion euros has been authorised for the first phase, which will cover the construction costs of a fully working telescope with a suite of powerful instruments and first light targeted in ten years time. It will enable tremendous scientific discoveries in the fields of exoplanets, the stellar composition of nearby galaxies and the deep Universe. The largest ESO contract ever, for the telescope dome and main structure, will be placed within the next year.

Alien life arrested by climate catch-22

3 December 2014 - 6:30pm
Other Earth-like planets may be caught in a dilemma – they need stable, warm climates to support complex life, but a lack of life may preclude this

Spotted: First quadruple star image produced by gravity

3 December 2014 - 6:25pm
A newly discovered supernova and its four gravitationally lensed images may give researchers a way to pin down the universe's expansion rate

Hayabusa 2 probe begins journey to land on an asteroid

3 December 2014 - 1:20pm
Japanese space agency JAXA has successfully launched Hayabusa 2, which will land on asteroid 1993 JU3 in 2018

Astrophysics: Stars fight back

3 December 2014 - 12:00am

Astrophysics: Stars fight back

Nature 516, 7529 (2014). doi:10.1038/516044a

Authors: Philip F. Hopkins

Galaxies contain fewer stars than predicted. The discovery of a massive galactic outflow of molecular gas in a compact galaxy, which forms stars 100 times faster than the Milky Way, may help to explain why. See Letter p.68

Stellar feedback as the origin of an extended molecular outflow in a starburst galaxy

3 December 2014 - 12:00am

Stellar feedback as the origin of an extended molecular outflow in a starburst galaxy

Nature 516, 7529 (2014). doi:10.1038/nature14012

Authors: J. E. Geach, R. C. Hickox, A. M. Diamond-Stanic, M. Krips, G. H. Rudnick, C. A. Tremonti, P. H. Sell, A. L. Coil & J. Moustakas

Recent observations have revealed that starburst galaxies can drive molecular gas outflows through stellar radiation pressure. Molecular gas is the phase of the interstellar medium from which stars form, so these outflows curtail stellar mass growth in galaxies. Previously known outflows, however, involve small fractions of the total molecular gas content and have typical scales of less than a kiloparsec. In at least some cases, input from active galactic nuclei is dynamically important, so pure stellar feedback (the momentum return into the interstellar medium) has been considered incapable of rapidly terminating star formation on galactic scales. Molecular gas has been detected outside the galactic plane of the archetypal starburst galaxy M82 (refs 4 and 5), but so far there has been no evidence that starbursts can propel substantial quantities of cold molecular gas to the same galactocentric radius (about 10 kiloparsecs) as the warmer gas that has been traced by metal ion absorbers in the circumgalactic medium. Here we report observations of molecular gas in a compact (effective radius 100 parsecs) massive starburst galaxy at redshift 0.7, which is known to drive a fast outflow of ionized gas. We find that 35 per cent of the total molecular gas extends approximately 10 kiloparsecs, and one-third of this extended gas has a velocity of up to 1,000 kilometres per second. The kinetic energy associated with this high-velocity component is consistent with the momentum flux available from stellar radiation pressure. This demonstrates that nuclear bursts of star formation are capable of ejecting large amounts of cold gas from the central regions of galaxies, thereby strongly affecting their evolution by truncating star formation and redistributing matter.