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New Theory to Explain “Alien Probe” Asteroid

By David Reneke

A new theory explains the true identity of an “alien probe” asteroid, and the development of Australia’s first space telescope is underway.

When is a mystery not a mystery? When the explanations for it reach absurd levels and common sense flies out the window. If there’s one story that left astronomers truly scratching their heads in 2018, it had to be the mysterious interstellar visitor known as Oumuamua.

The odd cigar-shaped object flew through our solar system in late 2017, and researchers spent much of last year just trying to figure out what it was. Theories are many, and scientists have suggested the usual suspects including a comet or asteroid, as well as more “way out” possibilities like an alien ship or probe. Now veteran astronomer Zdenek Sekanina, a seasoned skywatcher with a long and successful track record, is offering an entirely new theory, and he thinks he might have the evidence to back it up.

Early speculation centred around Oumuamua being solid like a rock, a chunk of ice, or a mixture of the two. Drawing a long bow, others proposed a silent alien probe scanning the solar system and reporting back to its makers elsewhere.

Rather than a solid rock or chunk of debris, Sekanina explains that Oumuamua might be “a monstrous fluffy dust aggregate released via a recent explosive event”. The cloud of dust, swirling and spinning as it travels through space, would account for some of the more peculiar characteristics observed by astronomers.

One thing that researchers haven’t been able to explain about Oumuamua is that it seems to be speeding up as it travels away from the Sun. That shouldn’t happen to a body like an asteroid, which led some to consider the possibility that it was an alien craft with some kind of propulsion system or “light-sail” that allowed it to accelerate due to solar radiation pressure.

Basically, a mass of dust and gas may behave the same way, and it’s a more down-to-Earth theory than Oumuamua being a reconnaissance vehicle from an extra-terrestrial civilisation. Sekanina notes that additional research is obviously warranted, but this is a new wrinkle in the Oumuamua saga that could prove to be the answer researchers have been searching for.

Introducing SkyHopper, Australia’s First Space Telescope

Something special is happening in the basement of the School of Physics at the University of Melbourne. Innovative design is combining with new, low-cost nanosatellite technology to build Australia’s first space telescope, the SkyHopper. Recently, a team of scientists and researchers at Melbourne took delivery of the first pieces of hardware that may ultimately make it a reality.

The goal of SkyHopper is to break new ground in low-cost astronomy from space by advancing the state of the art in rapid follow-up of gamma-ray bursts originating in the infancy of the universe, and allowing us to discover potentially habitable Earth-sized exoplanets in our galactic neighbourhood.

Australia has entered a new chapter in the exploration and understanding of space by creating a National Space Agency. While the agency is still in its infancy, it’s already raising awareness of the opportunities space can offer as a platform for observations and communications.

In keeping with this new spirit of exploration, the University of Melbourne is leading the design with SkyHopper, which will also be able to measure the distance to stars that are exploding and collapsing into black holes at the edge of our observable universe.

With commercial space companies now providing low-cost hardware and launches for small “cube” satellites, all these goals suddenly become realistic for us to build and launch SkyHopper. The space telescope is envisioned to be launched in 2021, operating in low-Earth orbit.

The SkyHopper idea was conceived in June 2015 at The University of Melbourne by four scientists with diverse expertise and backgrounds. The expanded team now encompasses a consortium of 16 among the world’s leading institutions in Australia, the United States and Europe.

David Reneke is an astronomy lecturer, writer and broadcaster (