Institute of Astronomy

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Goals defined for UK's Lunar mission

Astronomy News - 8 December 2014 - 1:23am

Scientists set out the detailed scientific goals of a proposed UK-led mission to the Moon, including research into the feasibility of a human base there.

New Horizons Wakes Up on Pluto's Doorstep

Astronomy News - 7 December 2014 - 5:04pm
After a voyage of nearly nine years and three billion miles —the farthest any space mission has ever traveled to reach its primary target – NASA’s New Horizons spacecraft came out of hibernation on Dec. 6th for its long-awaited 2015 encounter with the Pluto system.

Giant galactic gas 'blow out' seen for the first time

Astronomy News - 5 December 2014 - 5:30pm

A gigantic rainbow jet has been glimpsed in the act of being booted out of a galactic nursery by the forming stars

Pluto probe prepares to wake after nine-year journey

Astronomy News - 5 December 2014 - 4:57pm
After an epic trip covering about 4.76 billion kilometres, the New Horizons spacecraft is about to arrive near Pluto and its remote, icy neighbours

Japan Launches Asteroid Mission

Astronomy News - 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...

Astronomy News - 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

Astronomy News - 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

Astronomy News - 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

Astronomy News - 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

Astronomy News - 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

Astronomy News - 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

Astronomy News - 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

Astronomy News - 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.

Is Jupiter's Great Red Spot a Sunburn?

Astronomy News - 28 November 2014 - 5:54pm
The ruddy color of Jupiter's Great Red Spot is likely a product of simple chemicals being broken apart by sunlight in the planet's upper atmosphere, according to a new analysis of data from NASA's Cassini mission. The results contradict the other leading theory for the origin of the spot's striking color -- that the reddish chemicals come from beneath Jupiter's clouds.

Naked nebula reveals astronomy's colour tricks

Astronomy News - 28 November 2014 - 4:10pm
A raw picture of the Helix nebula reveals the processing involved in creating stunning astronomical images

Conference Announcement: Planck 2014 - The microwave sky in temperature and polarization

Astronomy News - 28 November 2014 - 8:46am
The Planck Collaboration will present the latest scientific results from ESA’s Planck satellite during a conference to be held from 1 to 5 December 2014 in Ferrara, Italy.

JUICE mission gets green light for next stage of development

Astronomy News - 27 November 2014 - 2:00pm
The European Space Agency's JUICE (JUpiter ICy moons Explorer) mission has been given the green light to proceed to the next stage of development. This approval is a milestone for the mission, which aims to launch in 2022 to explore Jupiter and its potentially habitable icy moons.

A Colourful Gathering of Middle-aged Stars

Astronomy News - 26 November 2014 - 11:00am
The MPG/ESO 2.2-metre telescope at ESO’s La Silla Observatory in Chile has captured a richly colourful view of the bright star cluster NGC 3532. Some of the stars still shine with a hot bluish colour, but many of the more massive ones have become red giants and glow with a rich orange hue.

Astronomy: Cosmic triangles and black-hole masses

Astronomy News - 26 November 2014 - 12:00am

Astronomy: Cosmic triangles and black-hole masses

Nature 515, 7528 (2014). doi:10.1038/515498a

Authors: Martin Elvis

A geometric measurement of the distance to a nearby galaxy implies a larger mass for its central black hole than previously calculated, and a consequent increase for most other masses of such black holes. See Letter p.528

A dust-parallax distance of 19 megaparsecs to the supermassive black hole in NGC 4151

Astronomy News - 26 November 2014 - 12:00am

A dust-parallax distance of 19 megaparsecs to the supermassive black hole in NGC 4151

Nature 515, 7528 (2014). doi:10.1038/nature13914

Authors: Sebastian F. Hönig, Darach Watson, Makoto Kishimoto & Jens Hjorth

The active galaxy NGC 4151 has a crucial role as one of only two active galactic nuclei for which black hole mass measurements based on emission line reverberation mapping can be calibrated against other dynamical techniques. Unfortunately, effective calibration requires accurate knowledge of the distance to NGC 4151, which is not at present available. Recently reported distances range from 4 to 29 megaparsecs. Strong peculiar motions make a redshift-based distance very uncertain, and the geometry of the galaxy and its nucleus prohibit accurate measurements using other techniques. Here we report a dust-parallax distance to NGC 4151 of megaparsecs. The measurement is based on an adaptation of a geometric method that uses the emission line regions of active galaxies. Because these regions are too small to be imaged with present technology, we use instead the ratio of the physical and angular sizes of the more extended hot-dust emission as determined from time delays and infrared interferometry. This distance leads to an approximately 1.4-fold increase in the dynamical black hole mass, implying a corresponding correction to emission line reverberation masses of black holes if they are calibrated against the two objects with additional dynamical masses.