Michael ZS1MJT from HAMNET Western Cape has sent me a paragraph about the Rola Ford Motor Rally, held round and about Caledon in the Western Cape yesterday. In cool and cloudy conditions with a slight breeze, the race started from Rola Ford’s showrooms at 09h05.

Nine radio operators were deployed around the course, at various starts and ends of the 5 stages, and 16 vehicles took part, although 5 cars didn’t finish the course due to mechanical failures. He says there were no major calamities, as the radio operators radioed start and end times through to the JOC, as each car completed a stage.

The final stage ended with the arrival of the last car at 14h05, in a fine drizzle. The day was enjoyed by the operators and the spectators who had positioned themselves at all the major vantage points.

The operators were Ian ZS1BR, Andre ZS1ATX, Rassie ZS1YT, Davy ZR1FR, Hughie ZS1YS, Schalk ZR1SWB, Pieter ZS1PJG, Reg ZS1ADC and Michael ZS1MJT.

Thanks Michael for the report.

From the Cape Town section of the Mountain Club of South Africa, we learn that, in September 1889, a party of hikers on Table Mountain was caught by the infamous “Table Cloth” and forced to spend a cold night on the mountain.

The incident helped set the ball rolling towards the formation of the Mountain Club of South Africa in 1891. From the very beginning, one of MCSA’s objectives was to organise search and rescue parties to assist fellow mountaineers and members of the public in difficulty.

More than 130 years later, Search & Rescue remains a fundamental part of MCSA.

Today, MCSA Search & Rescue comprises five volunteer teams across South Africa, involved in hundreds of operations each year. Teams provide specialist support to government agencies and, when required, take the lead in organising and carrying out search and rescue operations in remote, wilderness and mountainous environments.

From that cold night on Table Mountain in 1889 to the highly trained volunteer teams operating across South Africa today, helping people in the mountains has been part of MCSA’s purpose from the very beginning.

Universetoday.com asks us where Earth’s center of mass is? The answer seems trivially obvious. It’s right in the middle of the planet. Ah, but that kind of thinking won’t get you a paper in the Geophysical Journal International. It’s also not a trivial question. Knowing Earth’s center of mass down to the order of millimeters reveals some interesting facts about our planet.

To measure Earth’s center of mass accurately, we must look to space. Satellites don’t just orbit Earth; they orbit the exact center of Earth’s mass. Any small shift in that center of mass means there is a shift in orbital trajectories. All you have to do is measure the orbits precisely. Back in the 1980s and 1990s, this was done using satellites known as LAGEOS. These spherical satellites were covered in reflective panels so that ground-based laser observatories could measure their positions over time. These allowed us to determine the center of mass to within a centimetre or so.

This new study improves this accuracy by using GPS data to account for tiny shifts in the locations of ground-based observatories. It also adds data from a host of low-orbit satellites to improve accuracy even further. The result reduces our uncertainty to less than a millimetre.

Part of the results is as we expected. The Earth is not a static mass. During the winter season of the Northern Hemisphere, snow and ice builds up in the polar region, which means there is more mass there. The warming and cooling of oceans shifts their densities. The rainy season of the Amazon moves water to its delta. All of this causes Earth’s center of mass to move seasonally.

The surprise is that this shift is smaller than we thought. The results of this study find a seasonal drift that is about half of earlier estimates. This means that there is less water and air moving between hemispheres. The two regions aren’t as interconnected as we assumed. The team also observed longer-term shifts in the center of mass due to geological effects such as volcanic activity and earthquakes. These shifts can also affect things such as Earth’s rotational speed.

Precise measurements such as these not only help us understand geological changes; they also help us better locate our location on Earth. It has an impact on everything from transportation and shipping to the orbital drift of satellite constellations. It’s also remarkable to think that we can pinpoint the middle of the Earth with such accuracy.

And heraldousa.com reports that Scientists have detected a radio signal transmitted from thousands of light-years away for the first time, from the exoplanet ‘Beta Pictoris b’,

The study was published on Sept. 15 in arXiv and was led by astrophysicists Kevin N. Ortiz Ceballos, Edo Berger and Yvette Cendes.

Researchers from the Harvard-Smithsonian Center for Astrophysics and the Department of Physics and Astronomy at the University of Oregon said that, until now, an “auroral radio emission” has never been detected on a planet outside the solar system.

To ease many minds, the radio signal from the exoplanet ‘β Pictoris b’ is not of human origin but a natural process recorded on planets, according to Avi Loeb, who led the research.

“The same radio-emission mechanism operates in the solar system and does not indicate a technological origin,” he said.

According to the specialists, the auroral radio emission is produced “by the electron-cyclotron maser instability” [whatever that is] and comes from a “gas giant” planet that is twelve times larger than Jupiter.

The frequency of the emission is determined by the intensity of the planet’s magnetic field.

While this is not the first time astrophysicists have detected a radio signal from a planet in the solar system, it is the first time one has been recorded on an exoplanet.

“Although auroral radio bursts are observed on planets in the solar system and on some ultracool dwarfs, no radio detection had previously been unambiguously traced to an extrasolar planet rather than its host star,” the study states.

The detected frequency from the planet β Pictoris ranges from 0.85 to 3.5 GHz, with a magnetic field of 1.25 kilo-Gauss or greater.

This is a significant finding for science, as it allowed for the direct measurement of the magnetic field intensity of the exoplanet.

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