Institute of Astronomy

Astronomy News

Quantum particles seen distorting light from a neutron star

1 December 2016 - 9:23am

Astronomers have at last observed polarisation of light by virtual particles in a neutron star's magnetic field, a long-expected quantum effect

Saturn mission approaches tour finale

1 December 2016 - 9:21am

The Cassini spacecraft is beginning the end phases of its mission to Saturn that will eventually see it disposed of in the giant planet's atmosphere.

First Signs of Weird Quantum Property of Empty Space?

30 November 2016 - 11:24am
By studying the light emitted from an extraordinarily dense and strongly magnetised neutron star using ESO’s Very Large Telescope, astronomers may have found the first observational indications of a strange quantum effect, first predicted in the 1930s. The polarisation of the observed light suggests that the empty space around the neutron star is subject to a quantum effect known as vacuum birefringence.

Proxima Centauri really does orbit its two bright neighbours

30 November 2016 - 10:59am

After a century of speculation, we now know the little planet-bearing star revolves around Alpha Centauri A and B every 550,000 years

Mars probe returns first pictures

30 November 2016 - 10:58am

The new satellite that Europe and Russia put in orbit at Mars on 19 October has sent back its first images of the planet.

Moon-dust cake mix shows moon may have had water from the start

29 November 2016 - 9:30am

Early moon geology recreated in the lab suggests water was there to begin with, not added later by comets

Corrigendum: Slowly fading super-luminous supernovae that are not pair-instability explosions

24 November 2016 - 9:29am

Corrigendum: Slowly fading super-luminous supernovae that are not pair-instability explosions

Nature 539, 7630 (2016). doi:10.1038/nature19850

Authors: M. Nicholl, S. J. Smartt, A. Jerkstrand, C. Inserra, M. McCrum, R. Kotak, M. Fraser, D. Wright, T.-W. Chen, K. Smith, D. R. Young, S. A. Sim, S. Valenti, D. A. Howell, F. Bresolin, R. P. Kudritzki, J. L. Tonry, M. E. Huber, A. Rest, A. Pastorello, L. Tomasella, E. Cappellaro, S. Benetti, S. Mattila, E. Kankare, T. Kangas, G. Leloudas, J. Sollerman, F. Taddia, E. Berger, R. Chornock, G. Narayan, C. W. Stubbs, R. J. Foley, R. Lunnan, A. Soderberg, N. Sanders, D. Milisavljevic, R. Margutti, R. P. Kirshner, N. Elias-Rosa, A. Morales-Garoffolo, S. Taubenberger, M. T. Botticella, S. Gezari, Y. Urata, S. Rodney, A. G. Riess, D. Scolnic, W. M. Wood-Vasey, W. S. Burgett, K. Chambers, H. A. Flewelling, E. A. Magnier, N. Kaiser, N. Metcalfe, J. Morgan, P. A. Price, W. Sweeney & C. Waters

Nature502, 346–349 (2013); doi:10.1038/nature12569In this Letter, we have identified an important error affecting Fig. 4 and Extended Data Fig. 6, as well as the values of some parameters derived from our model fits. We stress that

Magnetic reversals from planetary dynamo waves

24 November 2016 - 9:29am

Magnetic reversals from planetary dynamo waves

Nature 539, 7630 (2016). doi:10.1038/nature19842

Authors: Andrey Sheyko, Christopher C. Finlay & Andrew Jackson

A striking feature of many natural dynamos is their ability to undergo polarity reversals. The best documented example is Earth’s magnetic field, which has reversed hundreds of times during its history. The origin of geomagnetic polarity reversals lies in a magnetohydrodynamic process that takes place in Earth’s core, but the precise mechanism is debated. The majority of numerical geodynamo simulations that exhibit reversals operate in a regime in which the viscosity of the fluid remains important, and in which the dynamo mechanism primarily involves stretching and twisting of field lines by columnar convection. Here we present an example of another class of reversing-geodynamo model, which operates in a regime of comparatively low viscosity and high magnetic diffusivity. This class does not fit into the paradigm of reversal regimes that are dictated by the value of the local Rossby number (the ratio of advection to Coriolis force). Instead, stretching of the magnetic field by a strong shear in the east–west flow near the imaginary cylinder just touching the inner core and parallel to the axis of rotation is crucial to the reversal mechanism in our models, which involves a process akin to kinematic dynamo waves. Because our results are relevant in a regime of low viscosity and high magnetic diffusivity, and with geophysically appropriate boundary conditions, this form of dynamo wave may also be involved in geomagnetic reversals.

History: Women who read the stars

24 November 2016 - 9:27am

History: Women who read the stars

Nature 539, 7630 (2016). doi:10.1038/539491a

Author: Sue Nelson

Sue Nelson delights in Dava Sobel's account of a rare band of human computers.

Astrophysics: Homing in on a fast radio burst

24 November 2016 - 9:26am

Astrophysics: Homing in on a fast radio burst

Nature 539, 7630 (2016). doi:10.1038/539470b

The origins of powerful, millisecond-long radio pulses from space called fast radio bursts (FRBs) remain a mystery. But researchers studying the brightest FRB seen so far have zeroed in on its location more accurately than ever before.Vikram Ravi at the California Institute of Technology

Hubble rounds up the first worlds we’ll check for alien life

24 November 2016 - 9:24am

The space telescope is set to spend hundreds of hours over the next year picking out the perfect planet for its successor, the James Webb Space Telescope, to probe in earnest

Honour for software writer on Apollo moon mission

24 November 2016 - 9:22am

Barack Obama awards medal to Margaret Hamilton to recognise role in sending humankind into space.

Schiaparelli: Esa gives update on Mars crash investigation

24 November 2016 - 9:22am

The European Space Agency's preliminary report into the Schiaparelli crash on Mars confirms the probe became confused about its altitude.

Two-year extensions confirmed for ESA's science missions

23 November 2016 - 9:26am
ESA's Science Programme Committee (SPC) has today confirmed two-year mission extensions for nine scientific missions in which the Agency is participating. This secures their operations until the end of 2018.

A dash of hydrogen and methane could have kept Mars warm

23 November 2016 - 9:25am

The Red Planet’s thin atmosphere of carbon dioxide can’t retain enough heat for water to flow on the planet, but new calculations suggest how it was once warmer