Institute of Astronomy

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Planet smash-up 'brought carbon to Earth'

Astronomy News - 6 September 2016 - 9:26am

Much of Earth's life-giving carbon could have been delivered in an asteroid collision about 4.4 billion years ago, a theory suggests.

Here’s what colourful clouds on alien gas giants would look like

Astronomy News - 5 September 2016 - 9:18am

If you could hover over hot Jupiters in a spaceship, you might see deep blue skies and bright clouds, depending on how closely the planets hug their suns

Call for media: First data release from ESA's Gaia mission

Astronomy News - 2 September 2016 - 9:41am

Media representatives are invited to a briefing on the first data release of ESA's Gaia mission, an astrometry mission to map the stars of our galaxy, the Milky Way.

Stars burning strangely make life in the multiverse more likely

Astronomy News - 2 September 2016 - 9:38am

Supporters of the multiverse often cite a specific reaction in stars that seems tuned for life, making our universe improbable – but now there’s a new idea

'Ring of fire': Moon passes before Sun

Astronomy News - 2 September 2016 - 9:37am

Thousands of people have watched the Moon pass in front of the Sun, to make a so-called "ring of fire".

Aggregate dust particles at comet 67P/Churyumov–Gerasimenko

Astronomy News - 1 September 2016 - 10:05am

Aggregate dust particles at comet 67P/Churyumov–Gerasimenko

Nature 537, 7618 (2016). doi:10.1038/nature19091

Authors: Mark S. Bentley, Roland Schmied, Thurid Mannel, Klaus Torkar, Harald Jeszenszky, Jens Romstedt, Anny-Chantal Levasseur-Regourd, Iris Weber, Elmar K. Jessberger, Pascale Ehrenfreund, Christian Koeberl & Ove Havnes

Comets are thought to preserve almost pristine dust particles, thus providing a unique sample of the properties of the early solar nebula. The microscopic properties of this dust played a key part in particle aggregation during the formation of the Solar System. Cometary dust was previously considered to comprise irregular, fluffy agglomerates on the basis of interpretations of remote observations in the visible and infrared and the study of chondritic porous interplanetary dust particles that were thought, but not proved, to originate in comets. Although the dust returned by an earlier mission has provided detailed mineralogy of particles from comet 81P/Wild, the fine-grained aggregate component was strongly modified during collection. Here we report in situ measurements of dust particles at comet 67P/Churyumov–Gerasimenko. The particles are aggregates of smaller, elongated grains, with structures at distinct sizes indicating hierarchical aggregation. Topographic images of selected dust particles with sizes of one micrometre to a few tens of micrometres show a variety of morphologies, including compact single grains and large porous aggregate particles, similar to chondritic porous interplanetary dust particles. The measured grain elongations are similar to the value inferred for interstellar dust and support the idea that such grains could represent a fraction of the building blocks of comets. In the subsequent growth phase, hierarchical agglomeration could be a dominant process and would produce aggregates that stick more easily at higher masses and velocities than homogeneous dust particles. The presence of hierarchical dust aggregates in the near-surface of the nucleus of comet 67P also provides a mechanism for lowering the tensile strength of the dust layer and aiding dust release.

Planetary science: Cometary dust under the microscope

Astronomy News - 1 September 2016 - 10:05am

Planetary science: Cometary dust under the microscope

Nature 537, 7618 (2016). doi:10.1038/537037a

Authors: Ludmilla Kolokolova

The Rosetta spacecraft made history by successfully orbiting a comet. Data from the craft now reveal the structure of the comet's dust particles, shedding light on the processes that form planetary systems. See Letter p.73

Gang of gas giants may have tilted distant planet system

Astronomy News - 1 September 2016 - 10:00am

Astronomers track down one of the planets behind the first misaligned solar system ever found

NASA Extends Contract for Hubble Space Telescope Mission Operations

Astronomy News - 1 September 2016 - 9:59am
NASA has awarded a contract extension to Lockheed Martin Space Systems Corporation (LMSSC) of Greenbelt, Maryland, to continue maintaining the health and safety of the agency’s Hubble Space Telescope observatory through the next phase of its science mission.

First stars formed even later than previously thought

Astronomy News - 1 September 2016 - 9:57am

ESA's Planck satellite has revealed that the first stars in the Universe started forming later than previous observations of the Cosmic Microwave Background indicated. This new analysis also shows that these stars were the only sources needed to account for reionising atoms in the cosmos, having completed half of this process when the Universe had reached an age of 700 million years.

Imaging tiny comet dust in 3D

Astronomy News - 1 September 2016 - 9:56am

Rosetta has imaged the smallest grains of Comet 67P/Churyumov-Gerasimenko's dust yet, with its Micro-Imaging Dust Analysis System, MIDAS.

Mysterious signal unlikely to be aliens after SETI draws a blank

Astronomy News - 31 August 2016 - 9:23am

Radio telescopes across the world are swinging toward an intriguing signal that could point toward an intelligent extraterrestrial civilisation, but have come up empty

XMM-Newton reveals the Milky Way's explosive past

Astronomy News - 31 August 2016 - 9:21am

A giant bubble surrounding the centre of the Milky Way shows that six million years ago our Galaxy's supermassive black hole was ablaze with furious energy. It also shines a light on the hiding place of the Galaxy's so-called 'missing' matter.

New Solar System objects revealed

Astronomy News - 31 August 2016 - 9:19am

Astronomers in the US have uncovered previously unknown objects in the outer reaches of the Solar System.

Proxima b’s star could be blasting away the planet’s atmosphere

Astronomy News - 30 August 2016 - 9:56am

We’ve just found a potentially habitable exoplanet nearby, but monthly violent outbursts from the star Proxima Centauri could be bad news for life

Rosetta captures comet outburst

Astronomy News - 26 August 2016 - 9:02am

In unprecedented observations made earlier this year, Rosetta unexpectedly captured a dramatic comet outburst that may have been triggered by a landslide.

Proxima b: 7 big questions about the new planet next door

Astronomy News - 26 August 2016 - 9:00am

We’ve just discovered a planet in the nearest star system that could potentially host life. How do we find out more, and can we go visit?

Getting to Proxima b might become an existential requirement

Astronomy News - 26 August 2016 - 8:59am

Current starshot ventures to get to our new neighbour are too expensive to be practical, but finding out more about the planet should be a high priority

Ghost galaxy is 99.99 per cent dark matter with almost no stars

Astronomy News - 26 August 2016 - 8:59am

We've spotted a galaxy that weighs almost as much as the Milky Way yet has 1 per cent the number of stars, suggesting it’s chock-full of dark matter

Planet Found in Habitable Zone Around Nearest Star

Astronomy News - 25 August 2016 - 9:22am
Astronomers using ESO telescopes and other facilities have found clear evidence of a planet orbiting the closest star to Earth, Proxima Centauri. The long-sought world, designated Proxima b, orbits its cool red parent star every 11 days and has a temperature suitable for liquid water to exist on its surface. This rocky world is a little more massive than the Earth and is the closest exoplanet to us — and it may also be the closest possible abode for life outside the Solar System. A paper describing this milestone finding will be published in the journal Nature on 25 August 2016.