Dave Higgs, ZS2DH, of HAMNET Eastern Cape has told us about the Transbaviaans Mountain Bike event, which is taking place this weekend and at which PEARS and HAMNET EC are assisting. We look forward to a report on this race from you in the future, Dave.
The scientific part of our HAMNET report today says that the Planetary Society reports that its crowdfunded LightSail 2 spacecraft is successfully raising its orbit solely on the power of sunlight. Since unfurling the spacecraft’s solar sail on July 23, mission managers have been optimizing the way the spacecraft orients itself during solar sailing. After a few tweaks, LightSail 2 began raising its orbital apogee, something the mission team said demonstrated the mission’s primary goal of “flight by light for CubeSats.” Continuing to sail on sunlight in Earth orbit, the spacecraft’s orbital apogee hit 729 kilometres as of August 5, an increase of 3.2 kilometres since sail deployment.
LightSail 2 launched on June 25, and it deployed on July 2 from Prox-1, a Georgia Tech student-built spacecraft the size of a small washing machine. Using the Experimental License call sign WM9XPA, LightSail 2 automatically transmits a beacon packet on 437.025 MHz at 9,600 bps FSK every few seconds, which can be decoded into 238 lines of text telemetry describing the spacecraft’s health and status — everything from battery status to solar sail deployment motor state. Every 45 seconds, the spacecraft transmits “LS2” in CW on 437.025 MHz.
Thanks to the ARRL Letter for this interesting insert.
Science News reports that shudders in the cosmos have revealed what’s likely the sad end of a neutron star — getting swallowed by a black hole.
If confirmed, it would be the first solid detection of this source of gravitational waves, revealing a type of cataclysm never before spotted. Researchers from the LIGO and Virgo gravitational wave observatories reported the candidate event, which was detected on August 14, in a public database used by astronomers.
Scientists are still analysing the data to verify what created the gravitational waves, which are tiny vibrations in spacetime caused by massive, accelerating objects. But one thing seems fairly certain: “Something has occurred out there in the sky,” says physicist Daniel Holz of the University of Chicago, a member of LIGO. “So far, it doesn’t obviously look like anything we’ve detected with high confidence before.”
LIGO and Virgo previously have picked up gravitational waves from pairs of merging black holes and from colliding neutron stars, which are extremely dense collapsed stars. In April, scientists saw tentative hints of a rendezvous between a black hole and neutron star, but the signal was weak and could have been a false one.
This new discovery offers much more solid evidence: The detection was so clear that it’s considered very unlikely to be a false alarm. The researchers estimate that the run-in between the two objects occurred around 900 million light-years away, and within an area about 23 square degrees across the sky. (For comparison, the moon is about half a degree across.) Astronomers have since been peering at that region with their telescopes, looking for any light that may have been emitted in the merger. Such light could have been released if the neutron star were torn apart by the black hole before being gulped within its depths.
Further study of the encounter could help reveal new secrets about some of the universe’s most mysterious objects. But the potential detection is exciting on its own, Holz says. “The first of anything is always really fascinating.”
Now for the medical news in today’s bulletin, an excerpt in Science News, written by Aimee Cunningham reports that an especially dangerous type of tuberculosis may have met its match.
The U.S. Food and Drug Administration announced on August 14 that it has approved the antibiotic Pretomanid to help tackle what’s called extreme drug-resistant tuberculosis. This form of the disease is resistant to at least four of the main TB drugs, and treatment often fails. Only around 34 percent of infected patients typically survive, the World Health Organization says.
The current treatment requires patients to take as many as eight antibiotics orally, and sometimes by injection, for 18 months or more. By contrast, the new antibiotic is paired with two other previously approved drugs, Bedaquiline and Linezolid, in a six-month course of pills. Ninety-five of 107 patients who had the highly resistant disease and took this drug regimen recovered, according to the TB Alliance, the non-profit organization that developed Pretomanid. The drug is only the third since the 1960s to be approved for tuberculosis, which is caused by Mycobacterium tuberculosis.
Tuberculosis sickened an estimated 10 million people in 2017. Around 558,000 cases were multidrug-resistant, unresponsive to the two most powerful TB drugs. Of those cases, about 8.5 percent, or roughly 47,000, were extensively drug-resistant, according to WHO.
Pretomanid has been tested only in patients with highly resistant TB. More research is needed to determine whether the drug could be useful for the vast majority of patients who have TB that’s more receptive to treatment, says William Bishai, a tuberculosis researcher at the Johns Hopkins University School of Medicine, who was not involved in the drug’s development. Perhaps the standard regimen of multiple drugs taken for six months could be shortened by including the new antibiotic, he says. “We’re delighted to have this new drug Pretomanid, but there’s a lot more to do.”
And, in further medical news, Science News says that two Ebola treatments have proven to be effective in preventing death during a clinical trial conducted amid the ongoing Ebola outbreak in Congo, preliminary data suggest.
The trial began in November, with participants randomly given one of four experimental treatments. Data from 499 patients reviewed on August 9 suggest that those people taking one of two antibody treatments — mAb114 or REGN-EB3 — had a greater chance of survival than those on the antiviral drug Remdesivir or the antibody treatment ZMapp. Researchers reported the trial results in a news release on August 12th, but these findings have yet to be finalized.
“One thing that won’t change is that those two therapies are better than the other two — that’s for sure,” says Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health in Bethesda, Md. The trial now enters a phase with only the two most effective treatments in order to gather more data on their safety and the immune response to each drug. Researchers won’t study enough patients, however, to determine which drug works best.
The percentage of patients who died while taking one of the two treatments was in the region of 29 to 34 percent. That’s a big improvement over the current 67 percent mortality rate reported for Congo’s outbreak, which began on August 1, 2018.
The successful conclusion of this ground-breaking research will make a huge difference to the risks of Haemorrhagic Fevers in Central Africa.
This is Dave Reece ZS1DFR reporting for HAMNET in South Africa.