Astrophysics: Portrait of a dynamic neighbour

Nature 505, 7485 (2014). doi:10.1038/505625a

Authors: Adam P. Showman

Brown dwarfs are celestial objects that lack the mass to become fully fledged stars. High-resolution maps of one such object add to the evidence that these exotic worlds have highly dynamic weather and climate. See Letter p.654

Solar System evolution from compositional mapping of the asteroid belt

Nature 505, 7485 (2014). doi:10.1038/nature12908

Authors: F. E. DeMeo & B. Carry

Advances in the discovery and characterization of asteroids over the past decade have revealed an unanticipated underlying structure that points to a dramatic early history of the inner Solar System. The asteroids in the main asteroid belt have been discovered to be more compositionally diverse with size and distance from the Sun than had previously been known. This implies substantial mixing through processes such as planetary migration and the subsequent dynamical processes.

A global cloud map of the nearest known brown dwarf

Nature 505, 7485 (2014). doi:10.1038/nature12955

Authors: I. J. M. Crossfield, B. Biller, J. E. Schlieder, N. R. Deacon, M. Bonnefoy, D. Homeier, F. Allard, E. Buenzli, Th. Henning, W. Brandner, B. Goldman & T. Kopytova

Brown dwarfs—substellar bodies more massive than planets but not massive enough to initiate the sustained hydrogen fusion that powers self-luminous stars—are born hot and slowly cool as they age. As they cool below about 2,300 kelvin, liquid or crystalline particles composed of calcium aluminates, silicates and iron condense into atmospheric ‘dust’, which disappears at still cooler temperatures (around 1,300 kelvin). Models to explain this dust dispersal include both an abrupt sinking of the entire cloud deck into the deep, unobservable atmosphere and breakup of the cloud into scattered patches (as seen on Jupiter and Saturn). However, hitherto observations of brown dwarfs have been limited to globally integrated measurements, which can reveal surface inhomogeneities but cannot unambiguously resolve surface features. Here we report a two-dimensional map of a brown dwarf’s surface that allows identification of large-scale bright and dark features, indicative of patchy clouds. Monitoring suggests that the characteristic timescale for the evolution of global weather patterns is approximately one day.

Blobby galaxies with long glowing tendrils of stars could help explain why spiral galaxies are unusually rare in large clusters
    

Stephen Hawking has changed his mind about what black holes are – not for the first time. Take a journey through the biggest shifts in black hole lore
    

US struggles to offload telescopes

Nature 505, 7485 (2014). http://www.nature.com/doifinder/10.1038/505594a

Author: Alexandra Witze

West Virginia radio observatory seeks money from partners to fend off closure by the National Science Foundation.

LJ Rich finds how to photograph the stars without the need for expensive equipment.

The world's most famous living scientist has a new mind-bending theory about black holes. Rather than getting sucked into a singularity of confusion, read our explainer
    

NASA's James Webb Space Telescope has passed its first significant mission milestone for 2014 -- a Spacecraft Critical Design Review (SCDR) that examined the telescope's power, communications and pointing control systems.

The closest supernova seen for several decades has been spotted by students at University College London.

Scientists using the Herschel space observatory have made the first definitive detection of water vapor on the largest and roundest object in the asteroid belt, dwarf planet Ceres.

The nearest exploding star detected since 1987 could offer insights into dark energy, ghostly neutrinos, and even how the universe's story will play out
    

Take a dip in the Lagoon Nebula, a stellar nursery where bright new stars are being formed
    

ESA's Herschel space observatory has discovered water vapour around Ceres, the first unambiguous detection of water vapour around an object in the asteroid belt.

The first direct detection of water vapour from Ceres hints that the tiny world has a layer of buried ice or perhaps even slushy volcanoes
    

Scientists using the Herschel space observatory have made the first definitive detection of water vapor on the largest and roundest object in the asteroid belt, Ceres.

The VLT Survey Telescope (VST) at ESO's Paranal Observatory in Chile has captured this richly detailed new image of the Lagoon Nebula. This giant cloud of gas and dust is creating intensely bright young stars, and is home to young stellar clusters. This image is a tiny part of just one of eleven public surveys of the sky now in progress using ESO telescopes. Together these are providing a vast legacy of publicly available data for the global astronomical community.

Localized sources of water vapour on the dwarf planet (1) Ceres

Nature 505, 7484 (2014). doi:10.1038/nature12918

Authors: Michael Küppers, Laurence O’Rourke, Dominique Bockelée-Morvan, Vladimir Zakharov, Seungwon Lee, Paul von Allmen, Benoît Carry, David Teyssier, Anthony Marston, Thomas Müller, Jacques Crovisier, M. Antonietta Barucci & Raphael Moreno

The ‘snowline’ conventionally divides Solar System objects into dry bodies, ranging out to the main asteroid belt, and icy bodies beyond the belt. Models suggest that some of the icy bodies may have migrated into the asteroid belt. Recent observations indicate the presence of water ice on the surface of some asteroids, with sublimation a potential reason for the dust activity observed on others. Hydrated minerals have been found on the surface of the largest object in the asteroid belt, the dwarf planet (1) Ceres, which is thought to be differentiated into a silicate core with an icy mantle. The presence of water vapour around Ceres was suggested by a marginal detection of the photodissociation product of water, hydroxyl (ref. 12), but could not be confirmed by later, more sensitive observations. Here we report the detection of water vapour around Ceres, with at least 1026 molecules being produced per second, originating from localized sources that seem to be linked to mid-latitude regions on the surface. The water evaporation could be due to comet-like sublimation or to cryo-volcanism, in which volcanoes erupt volatiles such as water instead of molten rocks.

Solar system: Evaporating asteroid

Nature 505, 7484 (2014). doi:10.1038/505487a

Authors: Humberto Campins & Christine M. Comfort

The asteroid Ceres has been thought to contain abundant water. Observations acquired with the Herschel Space Observatory now show that this Solar System object is spewing water vapour from its surface. See Letter p.525

In Our Mathematical Universe Max Tegmark tries hard to make the seemingly outlandish theories of multiverses sound almost obvious and unavoidable