Australasian Science: Australia's authority on science since 1938
Out of this World
News from space and astronomy communities around the world.
How Much Does the Milky Way Weigh?
By David Reneke
How much does the Milky Way weigh?
Our home galaxy is a massive star-studded conglomeration more than 100,000 light years across. Calculating the weight of something so colossal seems beyond the realm of possibility, especially when peering from the inside out. However, Canadian astronomers at McMaster University have calculated that the Milky Way is a little lighter than previously believed, with a mass equivalent to about 700 billion suns!
A Habitable Planet May Be Just Around The Corner
By David Reneke
Astronomers have discovered the closest habitable planet outside our solar system, and discovered one of the biggest black holes ever.
Astronomers from the University of NSW have discovered the closest potentially habitable planet found outside our solar system so far, orbiting a star just 14 light years away. The planet, more than four times the mass of the Earth, is one of three that the team detected around a red dwarf star called Wolf 1061.
CSIRO Technology behind World’s Largest Telescope
By David Reneke
CSIRO technology is behind the world’s largest single dish radio telescope, and astronomers have found a peanut-shaped galaxy.
The National Astronomical Observatories of the Chinese Academy of Sciences has teamed up with CSIRO engineers to develop the world’s largest single dish radio telescope. The 500-metre Aperture Spherical Telescope (FAST) easily dwarfs the current largest single dish telescope, the Arecibo Observatory in Puerto Rico. It will also be one of the most sensitive, capable of receiving weaker and more distant radio signals, in turn helping to explore the nature, origins and evolution of the universe.
A “Baby Earth” in the Making
Astronomers may have seen a “baby Earth” forming, and have found that Saturn’s moons may be younger than the dinosaurs.
Recently released images from the Atacama Large Millimetre/submillimetre Array (ALMA) have revealed never-before-seen details of what astronomers believe may be a “baby Earth” or an even more massive “super-Earth” forming.
The images show a planet-forming disc around TW Hydrae, a Sun-like star close to Earth. The planet is about 10 million years old, making it a veritable newborn, floating in a ring of planet-forming material. Combined with its close proximity to Earth, TW Hydrae has become a popular study subject for researchers.
A New Spin on Star-Forming Galaxies
By Dave Reneke
Astronomers calculate that black holes at the heart of galaxies could swell to 50 billion times the mass of the Sun, and determine why some galaxies are “clumpy” rather than spiral in shape.
Australian researchers have discovered why some galaxies are “clumpy” rather than spiral in shape, and it appears low spin is to blame. The finding challenges an earlier theory that high levels of gas cause clumpy galaxies, and sheds light on the conditions that brought about the birth of most of the stars in the universe.
Most Earth-Like Worlds Are Unborn
An artist's impression of innumerable Earth-like planets that have yet to be born over the next trillion years in the evolving universe. Credit: ESA/NASA
Astronomers have peered behind the Milky Way and determined that 92% of habitable planets have not yet been born.
An assessment of data collected by NASA’s Hubble Space Telescope and the Kepler space observatory has determined that only 8% of the potentially habitable planets that will ever form in the universe existed when our solar system was born 4.6 billion years ago.
“Our main motivation was understanding the Earth’s place in the context of the rest of the universe,” said study author Peter Behroozi of the Space Telescope Science Institute in Baltimore. “Compared to all the planets that will ever form in the universe, the Earth is actually quite early.”
A Milestone in Predicting Solar Flares
By Dave Reneke
A milestone in predicting solar flares, and the discovery of a global ocean on Saturn’s moon Enceladus.
Solar flares are massive explosions in the Sun’s atmosphere. A single “monster” solar flare could cause up to $2 trillion worth of damage on Earth, including the loss of satellites and electricity grids. It also poses potential dangers to human life and health.
However, a new technique published in Nature Physics (tinyurl.com/oykoy8b) will allow changes in the Sun’s magnetic fields, which drive the initiation of solar flares, to be monitored up to ten times faster than previous methods, allowing for greater advanced warning of potentially devastating space storms.
Pulsar Glitches Help to Weigh a Star
By Dave Reneke
Pulsar glitches help to weigh a star, and Jupiter’s Great Red Spot is shrinking.
Researchers from the University of Southampton have developed a new method for measuring the mass of pulsars, highly magnetised rotating neutron stars formed from the remains of massive stars after they explode into supernovae.
Regional Processes Led to Huge Martian Floods
By David Reneke
Regional processes led to huge Martian floods, and interstellar seeds could have created oases of life throughout the universe.
Gigantic groundwater outbursts created the largest flood channels in the solar system on Mars 3.2 billion years ago. For many years it was thought that this was caused by the release of water from a global water table, but research carried out by the Planetary Science Institute reveals that the source was regional deposits of sediment and ice set in place 450 million years earlier.
“The flooding is due to regional processes, not global processes,” said J. Alexis P. Rodriguez, who was lead author of the research published in Scientific Reports (http://tinyurl.com/pbgoy5v).
A Village on the Moon
By Dave Reneke
The ESA wants to build a Moon base, and the search for ET scales up
It’s been almost 50 years since humans have set foot on the Moon. Now, the European Space Agency is planning to go back and move in.
“Why not have a Moon village?” asked Johann-Dietrich Woerner, the new director general of the ESA. “I don’t mean a few houses, the town hall and a church – the Moon village would consist of a settlement using the capabilities of different space-faring nations in the fields of robotic as well as human activities.”
Australasian Science July/August 2019
