Articles on Astrophysics

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The Andromeda galaxy and its companions is challenging the very foundations of cosmology. Adam Evans/Wikimedia Commons

Cosmic dance challenges our understanding of the universe

Deep images of the sky reveal that the universe contains billions of galaxies. Some, such as our own Milky Way, are immense, containing hundreds of billions of stars. Most galaxies, however, are dwarfs…
The SKA is on the horizon, but how do we get from here to there? Pete Wheeler, ICRAR

Aspiration vs delivery: the long road to the Square Kilometre Array

The Square Kilometre Array (SKA) radio telescope has been on the cards since the early 1990s. It took until May of last year to find out where it will be built – in South Africa, Australia and New Zealand…
The black hole at the centre of NGC 1277 galaxy is one of the largest ever discovered. NASA /ESA/Andrew C. Fabian/Remco C. E. van den Bosch (MPIA)

‘Overmassive’ black hole holds the mass of 17 billion suns

Astronomers have discovered a new, enormous black hole that could change our understanding of how galaxies evolve. Holding the mass of 17 billion suns, the black hole at the centre of the NGC 1277 galaxy…
The explosion of a super-luminous supernovae can emit as much light as our sun will in 10 billion years. Rampant.Gaffer

Super-luminous supernovae: seriously worth the superlatives

Supernovae are the brilliant, explosive deaths of stars. For a short time, these explosions can outshine an entire galaxy containing billions of stars. A recently discovered rare class of supernovae, termed…
Alpha Centauri is the closest star system to our own sun and appears to be home to at least one planet. EPA/Davide De Martin/ESO

Alpha Centauri exoplanet is the closest ever – how was it found?

Earlier this week, a Swiss-based team searching for planets outside our solar system (exoplanets) published a paper in Nature announcing the detection of an Earth-mass planet orbiting the star Alpha Centauri…
Three years ago we discovered water on the moon, and now we’ve worked out where it’s from. Jason Bache

Blowin’ in the (solar) wind: how the moon got its water

A study published in the journal Nature Geoscience last week suggests water on the moon may have come, at least in part, from the sun. Until a few years ago the orthodox view was that the moon was bone-dry…
Things may not be as they’d previously seemed regarding the moon’s formation. NASA/JPL-Caltech

Was the moon formed by a planetary hit-and-run?

New research published in the planetary science journal Icarus, shows the moon may have been formed by a glancing collision with an “impactor” in the violent days of the early solar system. Contrary to…
Despite ongoing research, we still know little about the universe’s earliest moments. tychay

‘Melbourne researchers rewrite Big Bang theory’ … or not

Earlier this week, headlines in several major newspapers screamed: “Melbourne researchers rewrite Big Bang theory”. You might think this is a reference to a new script for a popular TV show, but as a cosmologist…
Ripples in a pond help to illustrate wave motion and the Doppler effect. *˜Dawn˜*

Explainer: the Doppler effect

When an ambulance passes with its siren blaring, you hear the pitch of the siren change: as it approaches, the siren’s pitch sounds higher than when it is moving away from you. This change is a common…
There’s far more to the night sky than the human eye can see. Joseph Dsilva

Explainer: radio astronomy

Humans have always had a deep affinity with the night sky. Over millennia the stars have guided us in our travels, provided a grand canvas for the great stories of mythology and invoked a sense of wonder…
A simulated Black Hole of ten solar masses as seen from a distance of 600km with the Milky Way in the background. Ute Kraus/Wikimedia

Explainer: black holes

The concept of a “black hole” is one of the most curious in astrophysics. It’s the answer to the question: “What happens if the density of matter in a region becomes so high that not even light can escape…
Don’t look at the transit of Venus directly … but make sure you look at it. Jan Herold

Transit of Venus: a must-see for everyone … no seriously

When Australia II won the America’s Cup yacht race in 1983, then-prime-minister Bob Hawke famously exclaimed: “Any boss who sacks anyone for not turning up today is a bum.” Taking inspiration from this…
Everyone’s getting a slice of the SKA, whichever way you cut it. swishphotos

Science vs politics in the SKA decision: the winner was …

Late last week, the Square Kilometre Array (SKA) board chairman, John Womersley, announced that the future telescope will have more than one home: Australia/New Zealand and South Africa. The announcement…
The global push to detect gravitational waves could provide an enormous return for science. Wikimedia Commons

Rippling space-time: how to catch Einstein’s gravitational waves

Albert Einstein made an executive decision to revolutionise our understanding of gravity in a paper published in 1916. Nearly 100 years on, a key prediction of Einstein’s theory has eluded direct detection…
Trojans such as (1173) Anchises appear to have been caught in Jupiter’s orbit, mid-flight. Dave Hosford

By Jupiter: the gas giant’s Trojans were captured, not pre-formed

You’ll remember that, about a year ago, Canadian astronomers announced the discovery of a small asteroid sharing the earth’s orbit. The asteroid in question, 2010 TK7, is a “planetary Trojan” – an object…
Knowing where cosmic rays don’t come from brings scientists another step closer to determining their origin. NSF/J. Yang

An extragalactic mystery: where do high-energy cosmic rays come from?

It’s been the defining question of high-energy astrophysics for the past century: where do cosmic rays come from? New findings from the IceCube Neutrino Observatory at the South Pole have brought us closer…

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