Institute of Astronomy

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Nanoflares in the sun’s plasma may cause its scalding atmosphere

Astronomy News - 10 October 2017 - 9:14am

Tiny explosions in the atmosphere may explain why the solar corona is a million degrees hotter than the sun’s surface

Giant black hole seen flickering on and off after galaxy snack

Astronomy News - 10 October 2017 - 9:13am

Active Galactic Nuclei occur when a black hole devours a cloud of gas and dust and shines really brightly. Now one has been seen doing it twice

The Scientific Quest to Explain Kepler’s Most Enigmatic Find

Astronomy News - 9 October 2017 - 9:27am

Some 1,500 light years from Earth, a mystery of stellar proportions is playing out. A singular star out there captured scientists’ and the public’s imagination in September 2015 with its strangely fluctuating brightness.

News Article Type: Homepage ArticlesPublished: Friday, October 6, 2017 - 11:32

Lunar volcanoes and lava lakes gave the early moon an atmosphere

Astronomy News - 9 October 2017 - 9:25am

The same volcanic eruptions that made the dark patches we can see on the moon spewed out enough hot gas to create an atmosphere billions of years ago

Controversial Thirty Meter Telescope gets go-ahead to build in Hawaii

Astronomy News - 6 October 2017 - 1:42pm

Controversial Thirty Meter Telescope gets go-ahead to build in Hawaii

Nature 550, 7674 (2017).

Author: Alexandra Witze

State board issues construction permit for project, but legal fight over telescope continues.

Gravitational wave detection wins physics Nobel

Astronomy News - 6 October 2017 - 1:42pm

Gravitational wave detection wins physics Nobel

Nature 550, 7674 (2017).

Author: Davide Castelvecchi

Rainer Weiss, Barry Barish and Kip Thorne share the 2017 prize for their work at LIGO to detect ripples in space-time.

A hybrid type Ia supernova with an early flash triggered by helium-shell detonation

Astronomy News - 6 October 2017 - 1:41pm

A hybrid type Ia supernova with an early flash triggered by helium-shell detonation

Nature 550, 7674 (2017). doi:10.1038/nature23908

Authors: Ji-an Jiang, Mamoru Doi, Keiichi Maeda, Toshikazu Shigeyama, Ken’ichi Nomoto, Naoki Yasuda, Saurabh W. Jha, Masaomi Tanaka, Tomoki Morokuma, Nozomu Tominaga, Željko Ivezić, Pilar Ruiz-Lapuente, Maximilian D. Stritzinger, Paolo A. Mazzali, Christopher Ashall, Jeremy Mould, Dietrich Baade, Nao Suzuki, Andrew J. Connolly, Ferdinando Patat, Lifan Wang, Peter Yoachim, David Jones, Hisanori Furusawa & Satoshi Miyazaki

Type Ia supernovae arise from the thermonuclear explosion of white-dwarf stars that have cores of carbon and oxygen. The uniformity of their light curves makes these supernovae powerful cosmological distance indicators, but there have long been debates about exactly how their explosion is triggered and what kind of companion stars are involved. For example, the recent detection of the early ultraviolet pulse of a peculiar, subluminous type Ia supernova has been claimed as evidence for an interaction between a red-giant or a main-sequence companion and ejecta from a white-dwarf explosion. Here we report observations of a prominent but red optical flash that appears about half a day after the explosion of a type Ia supernova. This supernova shows hybrid features of different supernova subclasses, namely a light curve that is typical of normal-brightness supernovae, but with strong titanium absorption, which is commonly seen in the spectra of subluminous ones. We argue that this early flash does not occur through previously suggested mechanisms such as the companion–ejecta interaction. Instead, our simulations show that it could occur through detonation of a thin helium shell either on a near-Chandrasekhar-mass white dwarf, or on a sub-Chandrasekhar-mass white dwarf merging with a less-massive white dwarf. Our finding provides evidence that one branch of previously proposed explosion models—the helium-ignition branch—does exist in nature, and that such a model may account for the explosions of white dwarfs in a mass range wider than previously supposed.

The sun’s energy could speed up dark matter so we can detect it

Astronomy News - 6 October 2017 - 1:32pm

If dark matter is made of ultra-light particles with very little energy, one way to find them is to catch them after they ricochet off the sun

Martian Moon Phobos in Thermal Infrared Image

Astronomy News - 6 October 2017 - 1:32pm

NASA's longest-lived mission to Mars has gained its first look at the Martian moon Phobos, pursuing a deeper understanding by examining it in infrared wavelengths.

News Article Type: Homepage ArticlesPublished: Thursday, October 5, 2017 - 11:08

Gravitational wave discoverers win physics Nobel prize

Astronomy News - 4 October 2017 - 9:23am
Rainer Weiss, Barry Barish and Kip Thorne share the Nobel prize for physics for their contributions to the LIGO gravitational wave detector

Hubble Is Paving Scientific Paths for NASA’s James Webb Space Telescope

Astronomy News - 4 October 2017 - 9:22am

NASA’s Hubble Space Telescope is helping identify potential celestial targets for the James Webb Space Telescope through a series of preparatory science observations to be completed before Webb is ready to make observations of its own.

News Article Type: Homepage ArticlesPublished: Tuesday, October 3, 2017 - 10:27

Gaia data help prepare for a rare celestial alignment of Neptune's largest moon

Astronomy News - 4 October 2017 - 9:21am

On 5 October 2017, the largest moon of Neptune will pass in front of a distant star. This rare event will temporarily block the star's light from Earth and provide an excellent opportunity to study the moon's intriguing atmosphere. Data from ESA's Gaia mission is allowing astronomers to precisely plan their observations.

Einstein's waves win Nobel Prize

Astronomy News - 4 October 2017 - 9:20am

The 2017 Nobel prize in physics has been awarded to three scientists for the detection of gravitational waves.

The team that tracked Sputnik - and the world's first intercontinental ballistic missile

Astronomy News - 4 October 2017 - 9:19am

How a British observatory played a crucial part in the Cold War.

Methane burps on young Mars helped it keep its liquid water

Astronomy News - 3 October 2017 - 9:27am

The mystery of how water on Mars lasted for millions of years may come down to methane explosions that warmed the planet enough to melt ice and make rivers flow

The mysterious bright spots on Ceres may have a common origin

Astronomy News - 3 October 2017 - 9:26am

The dwarf planet Ceres is dappled with mysterious bright splotches. Their make-up varies with location, but they may all come from the same process

Biomarker found in space complicates search for life on exoplanets

Astronomy News - 3 October 2017 - 9:24am

A molecule once thought to be a useful marker for life as we know it has been discovered around a young star and at a comet for the first time, suggesting these ingredients are inherited during the planet-forming phase.

ALMA and Rosetta Detect Freon-40 in Space

Astronomy News - 2 October 2017 - 4:40pm
Observations made with the Atacama Large Millimeter/submillimeter Array (ALMA) and ESA’s Rosetta mission, have revealed the presence of the organohalogen Freon-40 in gas around both an infant star and a comet. Organohalogens are formed by organic processes on Earth, but this is the first ever detection of them in interstellar space. This discovery suggests that organohalogens may not be as good markers of life as had been hoped, but that they may be significant components of the material from which planets form. This result, which appears in the journal Nature Astronomy, underscores the challenge of finding molecules that could indicate the presence of life beyond Earth.

The Strange Structures of the Saturn Nebula

Astronomy News - 2 October 2017 - 3:21pm
The spectacular planetary nebula NGC 7009, or the Saturn Nebula, emerges from the darkness like a series of oddly-shaped bubbles, lit up in glorious pinks and blues. This colourful image was captured by the powerful MUSE instrument on ESO’s Very Large Telescope (VLT), as part of a study which mapped the dust inside a planetary nebula for the first time. The map — which reveals a wealth of intricate structures in the dust, including shells, a halo and a curious wave-like feature — will help astronomers understand how planetary nebulae develop their strange shapes and symmetries.

Bursting with Starbirth [heic 1716]

Astronomy News - 2 October 2017 - 3:21pm

This oddly-shaped galactic spectacle is bursting with brand new stars. The pink fireworks in this image taken with the NASA/ESA Hubble Space Telescope are regions of intense star formation, triggered by a cosmic-scale collision. The huge galaxy in this image, NGC 4490, has a smaller galaxy in its gravitational grip and is feeling the strain.