Institute of Astronomy

Astronomy News

Rare cosmic balancing act makes Perseid meteor showers brighter

27 May 2016 - 4:09pm

The gravitational pulls of Saturn and Jupiter may make meteor showers more spectacular, and could explain 1993's "night of the howling dogs"

ESO Signs Largest Ever Ground-based Astronomy Contract for E-ELT Dome and Telescope Structure

26 May 2016 - 9:31am
At a ceremony in Garching bei München, Germany on 25 May 2016, ESO signed the contract with the ACe Consortium, consisting of Astaldi, Cimolai and the nominated sub-contractor EIE Group, for the construction of the dome and telescope structure of the European Extremely Large Telescope (E-ELT). This is the largest contract ever awarded by ESO and also the largest contract ever in ground-based astronomy. This occasion saw the unveiling of the construction design of the E-ELT. Construction of the dome and telescope structure will now commence.

Bloated baby black holes spotted in the distant universe

26 May 2016 - 9:30am

Two blobs detected in the distant, ancient universe may be the seeds of the supermassive black holes that now dominate every galaxy

A resonant chain of four transiting, sub-Neptune planets

26 May 2016 - 9:28am

A resonant chain of four transiting, sub-Neptune planets

Nature 533, 7604 (2016). doi:10.1038/nature17445

Authors: Sean M. Mills, Daniel C. Fabrycky, Cezary Migaszewski, Eric B. Ford, Erik Petigura & Howard Isaacson

Surveys have revealed many multi-planet systems containing super-Earths and Neptunes in orbits of a few days to a few months. There is debate whether in situ assembly or inward migration is the dominant mechanism of the formation of such planetary systems. Simulations suggest that migration creates tightly packed systems with planets whose orbital periods may be expressed as ratios of small integers (resonances), often in a many-planet series (chain). In the hundreds of multi-planet systems of sub-Neptunes, more planet pairs are observed near resonances than would generally be expected, but no individual system has hitherto been identified that must have been formed by migration. Proximity to resonance enables the detection of planets perturbing each other. Here we report transit timing variations of the four planets in the Kepler-223 system, model these variations as resonant-angle librations, and compute the long-term stability of the resonant chain. The architecture of Kepler-223 is too finely tuned to have been formed by scattering, and our numerical simulations demonstrate that its properties are natural outcomes of the migration hypothesis. Similar systems could be destabilized by any of several mechanisms, contributing to the observed orbital-period distribution, where many planets are not in resonances. Planetesimal interactions in particular are thought to be responsible for establishing the current orbits of the four giant planets in the Solar System by disrupting a theoretical initial resonant chain similar to that observed in Kepler-223.

Suppressing star formation in quiescent galaxies with supermassive black hole winds

26 May 2016 - 9:28am

Suppressing star formation in quiescent galaxies with supermassive black hole winds

Nature 533, 7604 (2016). doi:10.1038/nature18006

Authors: Edmond Cheung, Kevin Bundy, Michele Cappellari, Sébastien Peirani, Wiphu Rujopakarn, Kyle Westfall, Renbin Yan, Matthew Bershady, Jenny E. Greene, Timothy M. Heckman, Niv Drory, David R. Law, Karen L. Masters, Daniel Thomas, David A. Wake, Anne-Marie Weijmans, Kate Rubin, Francesco Belfiore, Benedetta Vulcani, Yan-mei Chen, Kai Zhang, Joseph D. Gelfand, Dmitry Bizyaev, A. Roman-Lopes & Donald P. Schneider

Quiescent galaxies with little or no ongoing star formation dominate the population of galaxies with masses above 2 × 1010 times that of the Sun; the number of quiescent galaxies has increased by a factor of about 25 over the past ten billion years (refs 1, 2, 3, 4). Once star formation has been shut down, perhaps during the quasar phase of rapid accretion onto a supermassive black hole, an unknown mechanism must remove or heat the gas that is subsequently accreted from either stellar mass loss or mergers and that would otherwise cool to form stars. Energy output from a black hole accreting at a low rate has been proposed, but observational evidence for this in the form of expanding hot gas shells is indirect and limited to radio galaxies at the centres of clusters, which are too rare to explain the vast majority of the quiescent population. Here we report bisymmetric emission features co-aligned with strong ionized-gas velocity gradients from which we infer the presence of centrally driven winds in typical quiescent galaxies that host low-luminosity active nuclei. These galaxies are surprisingly common, accounting for as much as ten per cent of the quiescent population with masses around 2 × 1010 times that of the Sun. In a prototypical example, we calculate that the energy input from the galaxy’s low-level active supermassive black hole is capable of driving the observed wind, which contains sufficient mechanical energy to heat ambient, cooler gas (also detected) and thereby suppress star formation.

Astrophysics: How black holes restrain old galaxies

26 May 2016 - 9:27am

Astrophysics: How black holes restrain old galaxies

Nature 533, 7604 (2016). doi:10.1038/533473a

Authors: Marc Sarzi

Supermassive black holes are thought to keep star formation under control by ejecting or stirring gas in galaxies. Observations of an old galaxy reveal a potential mechanism for how this process occurs. See Letter p.504

Physics: Invest in neutrino astronomy

26 May 2016 - 9:26am

Physics: Invest in neutrino astronomy

Nature 533, 7604 (2016). doi:10.1038/533462a

Author: Spencer Klein

Spencer Klein calls for bigger telescope arrays to catch particles from the most energetic places in the Universe.

VIDEO: Hunting universe's strangest particles

26 May 2016 - 9:13am

Deep underground, beneath Daya Bay in the south of China, scientists are hunting for the oddest particles in the cosmos - neutrinos.

Contract to construct giant telescope

26 May 2016 - 9:12am

The contract is signed that will lead to the construction of one of this century's key astronomical facilities - the European Extremely Large Telescope.

Students taste life as a space scientist in Cassini competition

25 May 2016 - 9:36am

Over the past 12 years, the NASA/ESA/ASI Cassini-Huygens mission has made numerous exciting discoveries and returned many stunning images of the Saturnian system. Saturn, its moons, and rings provide the inspiration behind the 'Cassini scientist for a day' competition that is designed to give school students a taste of life as a space scientist. More than 900 students from across Europe participated in the 2015–2016 competition and the winners have now been selected.

Hubble finds clues to the birth of supermassive black holes [heic1610]

25 May 2016 - 9:36am

Astrophysicists have taken a major step forward in understanding how supermassive black holes formed. Using data from Hubble and two other space telescopes, Italian researchers have found the best evidence yet for the seeds that ultimately grow into these cosmic giants.

NASA Telescopes Find Clues For How Giant Black Holes Formed So Quickly

25 May 2016 - 9:35am
Using data from NASA’s Great Observatories, astronomers have found the best evidence yet for cosmic seeds in the early universe that should grow into supermassive black holes.

Cranky young sun could have kickstarted life on Earth

24 May 2016 - 9:28am

Giant solar storms may have turned early Earth's atmosphere into a cosy blanket and also helped life get going

Incoming asteroids could crumble harmlessly before they hit us

23 May 2016 - 3:54pm

Stand down, Bruce Willis. Space rocks are much more brittle than Earth rocks, suggesting that asteroids on a collision course are more likely to burn up as fireballs in the sky

Are mystery Mars plumes caused by space weather?

23 May 2016 - 3:53pm

Mysterious high-rise clouds seen appearing suddenly in the martian atmosphere on a handful of occasions may be linked to space weather, say Mars Express scientists.

VIDEO: Building a new dish

23 May 2016 - 3:44pm

BBC science correspondent Rebecca Morelle travels to China to take a close up tour of the Five-hundred-metre Aperture Spherical Telescope - or Fast for short.

Close-up of the Red Planet [heic1609]

20 May 2016 - 9:22am

During May 2016 the Earth and Mars get closer to each other than at any time in the last ten years. The NASA/ESA Hubble Space Telescope has exploited this special configuration to catch a new image of our red neighbour, showing some of its famous surface features. This image supplements previous Hubble observations of Mars and allows astronomers to study large-scale changes on its surface.

Hubble Takes Mars Portrait Near Close Approach

20 May 2016 - 9:22am

Get larger image formats

On May 12, 2016, astronomers using NASA's Hubble Space Telescope captured this striking image of Mars, when the planet was 50 million miles from Earth. The photo reveals details as small as 20 miles to 30 miles across. This observation was made just a few days before Mars opposition on May 22, when the sun and Mars will be on exact opposite sides of Earth. Mars also will be 47.4 million miles from Earth. On May 30, Mars will be the closest it has been to Earth in 11 years, at a distance of 46.8 million miles. Mars is especially photogenic during opposition because it can be seen fully illuminated by the sun as viewed from Earth.

Mars was once devastated by giant 50-metre tsunamis

20 May 2016 - 9:21am

Massive waves once crashed over the shores of the Red Planet, which could explain why we struggle to see its coastlines today

Tadpole galaxy spawns stars after eating invisible gas cloud

20 May 2016 - 9:20am

New Hubble observations suggest a nearby tadpole galaxy collided with a gas cloud and started to grow – the same thing may have happened to the Milky Way