Science, not speculation, is essential to determine how SARS-CoV-2 reached humans

On Feb 19, 2020, we, a group of physicians, veterinarians, epidemiologists, virologists, biologists, ecologists, and public health experts from around the world, joined together to express solidarity with our professional colleagues in China.1 Unsubstantiated allegations were being raised about the source of the COVID-19 outbreak and the integrity of our peers who were diligently working to learn more about the newly recognised virus, SARS-CoV-2, while struggling to care for the many patients admitted to hospital with severe illness in Wuhan and elsewhere in China. It was the beginning of a global tragedy, the COVID-19 pandemic. According to WHO, as of July 2, 2021, the pandemic has resulted in 182 101 209 confirmed cases and 3 950 876 deaths, both undoubtedly underestimates of the real toll. The impact of the pandemic virtually everywhere in the world has been far worse than even these numbers suggest, with unprecedented additional social, cultural, political, and economic consequences that have exposed numerous flaws in our epidemic and pandemic preparedness and in local and global political and economic systems. We have observed escalations of conflicts that pit many parties against one another, including central government versus local government, young versus old, rich versus poor, people of colour versus white people, and health priorities versus the economy. The crisis has highlighted the urgent need to build a better understanding of how science proceeds and the complex, but critical, links science has with health, public health, and politics.Peer reviewe

Statement in support of the scientists, public health professionals, and medical professionals of China combatting COVID-19

We are public health scientists who have closely followed the emergence of 2019 novel coronavirus disease (COVID-19) and are deeply concerned about its impact on global health and wellbeing. We have watched as the scientists, public health professionals, and medical professionals of China, in particular, have worked diligently and effectively to rapidly identify the pathogen behind this outbreak, put in place significant measures to reduce its impact, and share their results transparently with the global health community. This effort has been remarkable. We sign this statement in solidarity with all scientists and health professionals in China who continue to save lives and protect global health during the challenge of the COVID-19 outbreak. We are all in this together, with our Chinese counterparts in the forefront, against this new viral threat

Coronal Heating as Determined by the Solar Flare Frequency Distribution Obtained by Aggregating Case Studies

Flare frequency distributions represent a key approach to addressing one of the largest problems in solar and stellar physics: determining the mechanism that counter-intuitively heats coronae to temperatures that are orders of magnitude hotter than the corresponding photospheres. It is widely accepted that the magnetic field is responsible for the heating, but there are two competing mechanisms that could explain it: nanoflares or Alfv\'en waves. To date, neither can be directly observed. Nanoflares are, by definition, extremely small, but their aggregate energy release could represent a substantial heating mechanism, presuming they are sufficiently abundant. One way to test this presumption is via the flare frequency distribution, which describes how often flares of various energies occur. If the slope of the power law fitting the flare frequency distribution is above a critical threshold, $\alpha=2$ as established in prior literature, then there should be a sufficient abundance of nanoflares to explain coronal heating. We performed $>$600 case studies of solar flares, made possible by an unprecedented number of data analysts via three semesters of an undergraduate physics laboratory course. This allowed us to include two crucial, but nontrivial, analysis methods: pre-flare baseline subtraction and computation of the flare energy, which requires determining flare start and stop times. We aggregated the results of these analyses into a statistical study to determine that $\alpha = 1.63 \pm 0.03$. This is below the critical threshold, suggesting that Alfv\'en waves are an important driver of coronal heating.Comment: 1,002 authors, 14 pages, 4 figures, 3 tables, published by The Astrophysical Journal on 2023-05-09, volume 948, page 7