Space and astronomy news
Last week we talked about how well the indigenous Australians followed the night sky. Well, it turns out, Australia is still an amazing place for astronomy. There are so many powerful observatories in Australia, and even more in the works.
Continue reading “Ep. 532: Modern Astronomy of Australia”
This week, we focus on the archaeoastronomy of another part of the world, this time from the indigenous people of Australia. Another group of people whose lives depended on knowing what was happening in the sky from season to season.
Continue reading “Ep. 531: Australian Indigenous Astronomy”
This year’s International Astronautical Congress is being held in Adelaide, Australia and the opening ceremonies of this meeting of ‘all things space’ included a special announcement. The Australian government announced that it will establish a new national space agency, with the hopes of growing Australia’s already vibrant space industry.
Michaelia Cash, Australian’s acting Minister of Industry, Innovation and Science was quoted as saying that Australia will not have a NASA but an agency “right for our nation, right for our industry … that will provide the vehicle for Australia to have a long-term strategic plan for space – a plan that supports the innovative application of space technologies and grows our domestic space industry, including through defense space procurement.”
Australia’s space industry is worth about $4 billion and already employs about 11,500 people. But proponents for creating a space agency for the country say it will help coordinate and expand the efforts.
Of course Australia has been very active in space exploration, being part of every deep-space mission NASA has flown with tracking and communications as part the Deep Space Network and the precursor system of dishes around the world. The tracking and communications dish at Parkes, Honeysuckle Creek, Tidbinbilla and Canberra were notoriously part of the Apollo missions, and several other large radio dishes in Australia have been listening to space to tease out astronomical details. Additionally, the Square Kilometer Array being built in Australia, New Zealand and South Africa will help us answer fundamental questions in astronomy and cosmology.
But still, many have said that Australia is one of the few major developed countries that do not have a space agency. New Zealand established their space agency last year. You can see a list of all the world’s space agencies from Heather Archuletta’s Pillownaut website.
Reportedly, the plan is to double the size of Australia’s current space capacity within five years and add thousands of new jobs, while taking advantage of new technology such as cubesats.
“We have longstanding ties with NASA, exploring space together and generating all of these jobs. And that’s the key point, it is a jobs industry-first agency,” astrophysicist Alan Duffy told ABC. “It’s designed to create satellites and new uses for the images that come from those satellites, and I don’t mean giant, bus-sized satellites of the ‘60s and ‘70s. Thanks to smartphones something the size of a toaster has the same capabilities as some of these historic launches. So we get to space cheaper and we can do more when we’re there.”
Reportedly, more details of the new space agency will be announced this week during the IAC, which is a gathering of thousands of global space experts, heads of other space agencies and private companies.
Sources: ABC, Sydney Morning Herald
It might seem unlikely, but tiny grains of minerals can help tell the story of early Earth. And researchers studying those grains say that 4.4 billion years ago, Earth was a barren, mountainless place, and almost everything was under water. Only a handful of islands poked above the surface.
Continue reading “Early Earth Was Almost Entirely Underwater, With Just A Few Islands”
New evidence found in northwestern Australia suggests that a massive asteroid, 20 to 30 kilometres in diameter, struck Earth about 3.5 billion years ago. This impact would have dwarfed anything experienced by humans, and dinosaurs, releasing as much energy as millions of nuclear weapons. Impacts this large can trigger earthquakes and tsunamis, and change the geological history of Earth.
The evidence was uncovered by Andrew Glikson and Arthur Hickman from the Australian National University. While drilling for the Geological Survey of Western Australia, the two obtained drilling cores from some of the oldest known sediments on Earth. Sandwiched between two layers of sediment were tiny glass beads called spherules, which were formed from vaporized material from the asteroid impact.
The enormity of this impact cannot be overstated. “The impact would have triggered earthquakes orders of magnitude greater than terrestrial earthquakes, it would have caused huge tsunamis and would have made cliffs crumble,” said Dr. Glikson, from the ANU Planetary Institute.
This asteroid impact is the second oldest one that we know of. It is also one of the largest found yet, and at 20 to 30 kilometers in diameter, it is 2 the 3 times the size of the famous Chicxulub asteroid that struck the Yucatan in Mexico. That impact is thought to be responsible for ending the age of dinosaurs on Earth.
The crater itself would have been hundreds of kilometers in diameter, though all traces of it are now gone. “Exactly where this asteroid struck the earth remains a mystery,” Dr. Glikson said. “Any craters from this time on Earth’s surface have been obliterated by volcanic activity and tectonic movements.”
“Material from the impact would have spread worldwide. These spherules were found in sea floor sediments that date from 3.46 billion years ago,” said Glikson.
At 3.46 billion years ago, this puts this impact event close to a period of time 4.1 to 3.8 billion years ago known as the Late Heavy Bombardment. This was a period of time when a disproportionate number of asteroids struck the Earth and the Moon, and probably Mercury, Venus, and Mars, too. The Late Heavy Bombardment was probably caused by the gas giants in our Solar System. As these planets migrated, their gravity caused enormous disruption, pulling objects in the asteroid belt and the Kuiper Belt into trajectories that sent them towards the inner Solar System.
The surfaces of Mercury and the Moon are covered in impact craters. Samples of rock from the lunar surface, brought back to Earth by the Apollo astronauts, have been subjected to isotopic dating. Their age is constrained to a fairly narrow band of time, corresponding to the Late Heavy Bombardment. Obviously, the Earth would have been subjected to the same thing. But on geologically active Earth, most traces of impact events have been erased. It’s the sediment that hints at these events.
Australia is geologically ancient, and contains some of the most ancient rocks on Earth. Glikson and Hickman found the glass spherules in cores while drilling at Marble Bar in north-western Australia. Because the sediment layer containing the spherules was preserved between two volcanic layers, its age was determined with great precision.
For over 20 years, Dr. Glikson has been searching for evidence of asteroid impacts. When these glass beads were found in the core samples, he suspected an asteroid impact. Testing confirmed that the levels of elements such as platinum, nickel and chromium, matched those in asteroids.
This is not the first evidence of impact events that Glikson has uncovered. In 2015, Glikson discovered evidence of another massive asteroid strike in the Warburton Basin in Central Australia. At that site, buried in the crust 30 kilometers deep, in rock that is 300 to 500 million years old, Glikson found evidence of a double impact crater covering an area 400 kilometers wide.
This crater was believed to be the result of an asteroid that broke into two before slamming into Earth. “The two asteroids must each have been over 10 kilometers (6.2 miles) across — it would have been curtains for many life species on the planet at the time,” said Glikson.
“There may have been many more similar impacts, for which the evidence has not been found, said Dr. Glikson. “This is just the tip of the iceberg. We’ve only found evidence for 17 impacts older than 2.5 billion years, but there could have been hundreds.”
Finding the sites of ancient impacts is not easy. Advances in satellite imaging helped locate and pinpoint the Chicxulub crater, and others. If there have been hundreds of enormous asteroid impacts, like Dr. Glikson suggests, then they would have had an equally enormous impact on Earth’s evolution. But pinpointing these sites remains elusive.
Performing observations in Australia is on many astronomers’ bucket lists, and this video timelapse shows you precisely why. Famous, world-class observatories, dark sky and the beautiful desolation of the desert combine in this award-winning sequence shot by Alex Cherney and posted on Vimeo.
Cherney writes that the video “is the result of over three years of work” and was the winner of the 2014 STARMUS astrophotography competition. Here are the observatories that are featured:
Which way to the center of the galaxy? This very creative — and gorgeous — view of the Milky Way was taken this past weekend (March 9, 2014) by astrophotographer Carlos Orue from Australia. Carlos said the Milky Way was so bright under these dark skies that “I almost needed sunnies to turn down the glare! Lots of green airglow visible too.” Also visible are the large and small Magallanic clouds.
While taking the images for this 14-image panorama, Carlos said he had lots of company: “Kangaroos, wallabies, wombats, emus, bunny rabbits and foxes.”
And just remember, according to Walt Disney, “That second star to the right shines in the night for you, to tell you that the dreams you plan really can come true.”
Want to get your astrophoto featured on Universe Today? Join our Flickr group or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.
Intense wild fires, or bush fires as they are called in Australia, are burning out of control across southeast Australia with authorities describing the condition as “catastrophic.” The huge fires were easily visible from the International Space Station on Tuesday and onboard, Canadian astronaut Chris Hadfield has been watching from above.
See more of his images below:
Officials say more than 130 fires, many uncontained, are burning in the heavily populated New South Wales state, where dry conditions are fueling the fires as temperatures reached 45 degrees and wind gusts reached more than 100 kilometers per hour.
In Tasmania, an island south of Australia, rescue officials are still trying to locate around 100 residents who have been missing after a fire tore through a village, destroying dozens of homes. You can see images from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite that were taken on January 7, 2013 at the Earth Observatory website.
Follow Chris Hadfield on Twitter to see more images.
Additional information on the bush fires from Voice of America
Night vision under a full Moon at Wallaman Falls in Queensland, Australia. Credit and copyright: Thierry Legault. Used by permission.
Astrophotographer extraordinaire Thierry Legault traveled to Australia for the Transit of Venus this past June, but he didn’t stop with just taking incredible images of the Transit and then head home to France. He’s just published an wonderful collection of night sky images he took from his time in Australia, including this beautifully stunning image of a ‘Moonbow’ over Wallaman Falls, located in between Townsville and Cairns in north Queensland. If you’ve not seen a Moonbow before, you’re probably not alone. Many times, they are only visible in long exposure photographs, as the Moonlight effect is usually too faint for human eyes to discern. But the Moonlight on the water mist from the falls creates a Moonbow.
“The gibbous Moon makes a Moonbow over the falls while a bright meteor crosses the Milky Way,” Thierry wrote to Universe Today, sharing his new images. “Other visitors were sleeping in the camping area, but not me!”
See his entire collection of his Australian Nights images from June 2012 — they’re simply wonderful, and confirms the beauty of the night sky from down under!
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With all of the activity that’s been occurring on the Sun recently, the aurorae have been exceptionally bright and have created quite a show to viewers – both on Earth as well as above it!
The image above was taken over the southern Indian Ocean by astronauts aboard the International Space Station. The southern lights – a.k.a. aurora australis – glow bright green and red in the upper layers of the atmosphere, creating a dazzling aerial display. (Click here to watch a movie of this.)
Shortly after, fires can be seen on the ground as the ISS passes over Australia:
From NASA’s Earth Observatory website:
Astronauts on the International Space Station (ISS) used a digital camera to capture several hundred photographs of the aurora australis, or “southern lights,” while passing over the Indian Ocean on September 17, 2011. You can see the flowing ribbons and rays below as the ISS passed from south of Madagascar to just north of Australia between 17:22 and 17:45 Universal Time. Solar panels and other sections of the ISS fill some of the upper right side of the photograph.
Auroras are a spectacular sign that our planet is electrically and magnetically connected to the Sun. These light shows are provoked by energy from the Sun and fueled by electrically charged particles trapped in Earth’s magnetic field, or magnetosphere. In this case, the space around Earth was stirred up by an explosion of hot, ionized gas from the Sun — a coronal mass ejection — that left the Sun on September 14, 2011.
In the second image above, and in the last frames of the movie, light from the ground replaces the light show in the sky. Wildfires and perhaps some intentionally set agricultural fires burn on the continent of Australia,with smoke plumes faintly visible in the night sky. A gold and green halo of atmospheric airglow hangs above the horizon in the distance.
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Airglow is created by particles in the upper atmosphere that have been charged by UV light from the Sun during the day releasing the energy at night as greenish-yellow visible light.
Fires on the ground, fires in the sky… the stars blazing all around, the Sun in its full glory and a never-ending view of our entire planet… what an incredible place the ISS must be to work in! Absolutely amazing!
And the skies of night were alive with light, with a throbbing, thrilling flame; Amber and rose and violet, opal and gold it came. It swept the sky like a giant scythe, it quivered back to a wedge; Argently bright, it cleft the night with a wavy golden edge.
— “The Ballad of the Northern Lights”, Robert Service
Read more on the NASA Earth Observatory.