HAMNET Report 27th December 2020

In a news letter sent out by SETI@home this week, the Search for Extra-Terrestrial Intelligence is being bolstered by a 20 billion channel SERENDIP SETI spectrometer for use at the 500 metre diameter FAST telescope in China. So, while the loss of Arecibo is still huge, it appears SETI was already working on the receiving potential of FAST, to assist in tracking intelligent signals.

It so happens that, this past April, after processing 20 years of Arecibo data, they put the volunteer component of SETI@home into hibernation. They’re now working on the final stage of data analysis: developing algorithms and software to reject radio interference and to identify and rank potential radio signals from extra-terrestrial civilizations.

Together with colleagues at Harvard, Caltech, and the University of California San Diego, they are also developing a new type of SETI observatory, called PANOSETI, that searches the whole sky simultaneously for visible and infrared pulses of light, perhaps coming from an extra-terrestrial civilization or from new astrophysical phenomena. They have built a prototype at Lick Observatory and are developing plans to build two domes, each one equipped with 45 telescopes pointing in different directions. So the search continues, unhindered by the loss of Arecibo.

On the subject of flares emitted by host stars that might affect planets in the goldilocks’ zone, EurasiaReview says that, although violent and unpredictable, stellar flares emitted by a planet’s host star do not necessarily prevent life from forming, according to a new North-western University study.

Emitted by stars, stellar flares are sudden flashes of magnetic imagery. On Earth, the sun’s flares sometimes damage satellites and disrupt radio communications. Elsewhere in the universe, robust stellar flares also have the ability to deplete and destroy atmospheric gases, such as ozone. Without the ozone, harmful levels of ultraviolet (UV) radiation can penetrate a planet’s atmosphere, thereby diminishing its chances of harbouring surface life.

By combining 3D atmospheric chemistry and climate modelling with observed flare data from distant stars, a North-western-led team discovered that stellar flares could play an important role in the long-term evolution of a planet’s atmosphere and habitability.

“We compared the atmospheric chemistry of planets experiencing frequent flares with planets experiencing no flares. The long-term atmospheric chemistry is very different,” said North-western’s Howard Chen, the study’s first author. “Continuous flares actually drive a planet’s atmospheric composition into a new chemical equilibrium.”

“We’ve found that stellar flares might not preclude the existence of life,” added Daniel Horton, the study’s senior author. “In some cases, flaring doesn’t erode all of the atmospheric ozone. Surface life might still have a fighting chance.”

The study will be published on Dec. 21 in the journal Nature Astronomy.

Now EuroNews is reporting on a giant iceberg, the size of a small country that broke away from the Antarctic in 2017.  Measuring 5,800 square kilometres, twice the size of Luxembourg, it was one of the largest icebergs ever recorded.

This vast mass of frozen water has been slowly drifting through the ocean since it made a break from the Larson C ice shelf on the Antarctic Peninsula three years ago. Tracked by satellites the berg, shaped like a hand with an outstretched index finger, began moving north in 2018.

That was until last year when the iceberg, labelled as A68, was quickly propelled into the Southern Atlantic by strong currents in the ocean.

During its travels, it has shrunk and broken in two, but its unpredictable nature is causing concern for conservationists. It is still so large that photographs captured by the UK Royal Air Force earlier this month couldn’t fit it into a single shot.

As the iceberg closed in on the wildlife haven of South Georgia in the southern Atlantic Ocean earlier this year, experts grew increasingly worried it could cause an environmental disaster.

“The iceberg is going to cause devastation to the sea floor by scouring the seabed communities of sponges, brittle stars, worms and sea-urchins, so decreasing biodiversity,” explains Professor Geraint Tarling, an ecologist at the British Antarctic Survey (BAS).

“These communities help store large amounts of carbon in their body tissue and surrounding sediment. Destruction by the iceberg will release this stored carbon back into the water and, potentially, the atmosphere, which would be a further negative impact.”

South Georgia is one of the world’s most important ecosystems. The remote island is home to millions of macaroni, gentoo and king penguins as well as seals, albatross and other rare wildlife. Of the 30 species of birds that breed there, 11 are considered to be threatened or near threatened by the IUCN.

With no permanent human inhabitants, (except the occasional DXpedition), the island has levels of biodiversity comparable to the Galapagos Islands. To preserve this valuable ecosystem, the Government of South Georgia & the South Sandwich Islands created one of the world’s largest Marine Protected Areas in the region in 2012.

“When you’re talking about penguins and seals during the period that’s really crucial to them – during pup- and chick-rearing – the actual distance they have to travel to find food (fish and krill) really matters. If they have to do a big detour, it means they’re not going to get back to their young in time to prevent them starving to death in the interim,” said Professor Tarling.

There was no Christmas Eve transmission from SAQ, the Alexanderson Alternator transmitting station in Sweden. The Grimeton World Heritage Foundation and Alexander GVV Friends Association cited “prevailing circumstances in our society” for the event cancellation.

“We find it sad to have to make this decision, but see it as a necessary measure to protect everyone involved,” the announcement continued. Past SAQ transmission events are chronicled on YouTube. “We truly regret this and hope for your understanding of the situation and continued support for the business. We hope that ‘our old lady’ can soon be heard on the air again,” the announcement concluded.

The vintage Alexanderson Alternator provided an electromechanical means of transmitting message traffic. It dates back to the early 1920s.

This Sunday, it is my pleasant duty to wish all our listeners and readers a very happy 2021, with good health and prosperity in large measure. We are still in the thick of the worldwide medical disaster situation, and owe it to our families and friends to remain cautious, considerate and protective, to await the arrival of sufficient vaccines to start generating herd immunity against the coronavirus, which will signal the end of the pandemic.

This is Dave Reece ZS1DFR reporting for HAMNET in South Africa.