Institute of Astronomy

Astronomy News

Next stop Earth: Hayabusa2 bids farewell to asteroid Ryugu

15 November 2019 - 9:13am

Nature, Published online: 14 November 2019; doi:10.1038/d41586-019-03514-3

Japanese craft’s mission is the first to gather material from under an an asteroid’s surface.

Generation of solar spicules and subsequent atmospheric heating

15 November 2019 - 9:11am

Spicules are rapidly evolving fine-scale jets of magnetized plasma in the solar chromosphere. It remains unclear how these prevalent jets originate from the solar surface and what role they play in heating the solar atmosphere. Using the Goode Solar Telescope at the Big Bear Solar Observatory, we observed spicules emerging within minutes of the appearance of opposite-polarity magnetic flux around dominant-polarity magnetic field concentrations. Data from the Solar Dynamics Observatory showed subsequent heating of the adjacent corona. The dynamic interaction of magnetic fields (likely due to magnetic reconnection) in the partially ionized lower solar atmosphere appears to generate these spicules and heat the upper solar atmosphere.

Hayabusa-2: Japan spacecraft leaves asteroid to head home

14 November 2019 - 9:17am

Hayabusa-2 will return with samples of the asteroid after its yearlong journey back to Earth.

With Mars Methane Mystery Unsolved, Curiosity Serves Scientists a New One: Oxygen

14 November 2019 - 9:15am
Portal origin URL: With Mars Methane Mystery Unsolved, Curiosity Serves Scientists a New One: OxygenPortal origin nid: 454935Published: Tuesday, November 12, 2019 - 10:00Featured (stick to top of list): noPortal text teaser: Scientists noticed something baffling on Mars: oxygen, the gas many Earth creatures use to breathe, behaves in a way that so far no one can explain through any known chemical processes.Portal image: Clouds on MarsScience Categories: Solar System

Far, Far Away in the Sky: New Horizons Kuiper Belt Flyby Object Officially Named 'Arrokoth'

14 November 2019 - 9:15am
Portal origin URL: Far, Far Away in the Sky: New Horizons Kuiper Belt Flyby Object Officially Named 'Arrokoth'Portal origin nid: 455094Published: Tuesday, November 12, 2019 - 11:27Featured (stick to top of list): noPortal text teaser: In a fitting tribute to the farthest flyby ever conducted by spacecraft, the Kuiper Belt object 2014 MU69 has been officially named Arrokoth, a Native American term meaning “sky” in the Powhatan/Algonquian language.Portal image: New Horizons Mission, 2014 MU69 Named 'Arrokoth'Science Categories: Solar System

Planet Mercury passes across the face of the Sun

12 November 2019 - 9:30am

Astronomers are observing a rare event, a transit of the planet Mercury.

SpaceX launch highlights threat to astronomy from ‘megaconstellations’

12 November 2019 - 9:30am

Nature, Published online: 11 November 2019; doi:10.1038/d41586-019-03446-y

Researchers fear that plans to send tens of thousands of communications satellites into orbit will disrupt scientific observations of the Universe.

Daily briefing: How to stop commercial satellites from disrupting astronomy

12 November 2019 - 9:29am

Nature, Published online: 11 November 2019; doi:10.1038/d41586-019-03480-w

The trouble with megaconstellations like SpaceX’s Starlinks, how to put your code in the cloud and about Russia’s raid on a top physics institute.

Hubble captures a dozen Sunburst Arc doppelgangers [heic1920]

11 November 2019 - 10:07am

Astronomers using the NASA/ESA Hubble Space Telescope have observed a galaxy in the distant regions of the Universe which appears duplicated at least 12 times on the night sky. This unique sight, created by strong gravitational lensing, helps astronomers get a better understanding of the cosmic era known as the epoch of reionisation.

AI Copernicus ‘discovers’ that Earth orbits the Sun

11 November 2019 - 10:07am

Nature, Published online: 07 November 2019; doi:10.1038/d41586-019-03332-7

A neural network that teaches itself the laws of physics could help to solve quantum-mechanics mysteries.

Ionizing photons escape a lensed galaxy

11 November 2019 - 10:06am

Gravitational lensing reveals ionizing ultraviolet photons escaping from a distant galaxy

11 November 2019 - 10:06am

During the epoch of reionization, neutral gas in the early Universe was ionized by hard ultraviolet radiation emitted by young stars in the first galaxies. To do so, ionizing ultraviolet photons must escape from the host galaxy. We present Hubble Space Telescope observations of the gravitationally lensed post-reionization galaxy PSZ1-ARC G311.6602–18.4624 (nicknamed the "Sunburst Arc"), revealing bright, multiply imaged ionizing photon escape from a compact star-forming region through a narrow channel in an optically thick gas. The gravitational lensing magnification shows how ionizing photons escape this galaxy, contributing to the reionization of the Universe. The multiple sight lines to the source probe absorption by intergalactic neutral hydrogen on a scale of less than a few hundred parsecs.

How massive can a spiral galaxy be?

11 November 2019 - 10:04am

NASA’s TESS Presents Panorama of Southern Sky

7 November 2019 - 9:27am
Portal origin URL: NASA’s TESS Presents Panorama of Southern SkyPortal origin nid: 454739Published: Tuesday, November 5, 2019 - 13:00Featured (stick to top of list): noPortal text teaser: The glow of the Milky Way — our galaxy seen edgewise — arcs across a sea of stars in a new mosaic of the southern sky produced from a year of observations by NASA’s Transiting Exoplanet Survey Satellite (TESS). Constructed from 208 TESS images, the panorama reveals both the beauty of the cosmic landscape and the reach of TESS’s cameras.Portal image: portion of TESS southern sky mosaic imageScience Categories: Universe

Voyagers shed light on Solar System's structure

5 November 2019 - 9:29am

Data from spacecraft launched in the 1970s help determine the shape of the magnetic bubble around the Sun.

Enter the 'terrascope'

1 November 2019 - 9:33am
Astronomer David Kipping from Columbia University is someone who always comes up with interesting ideas. He now wants to use the Earth's atmosphere as a giant lens to create a 'terrascope'.

NASA's James Webb Space Telescope nears completion

1 November 2019 - 9:32am
Engineers have successfully connected the two halves of NASA’s $8.8bn James Webb Space Telescope (JWST) for the first time.

SKA hit by further cost hike and delay

1 November 2019 - 9:31am
Plans to build the world’s largest radio telescope, known as the Square Kilometre Array (SKA), have suffered another setback after it emerged that the estimated cost of the observatory has risen by €100m over the past year.

A unified mechanism for unconfined deflagration-to-detonation transition in terrestrial chemical systems and type Ia supernovae

1 November 2019 - 9:31am

The nature of type Ia supernovae (SNIa)—thermonuclear explosions of white dwarf stars—is an open question in astrophysics. Virtually all existing theoretical models of normal, bright SNIa require the explosion to produce a detonation in order to consume all of stellar material, but the mechanism for the deflagration-to-detonation transition (DDT) remains unclear. We present a unified theory of turbulence-induced DDT that describes the mechanism and conditions for initiating detonation both in unconfined chemical and thermonuclear explosions. The model is validated by using experiments with chemical flames and numerical simulations of thermonuclear flames. We use the developed theory to determine criteria for detonation initiation in the single-degenerate Chandrasekhar-mass SNIa model and show that DDT is almost inevitable at densities of 107 to 108 grams per cubic centimeter.

A black hole hiding in a binary star

1 November 2019 - 9:30am