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The JunoCam imager aboard NASA's Juno spacecraft took this shot during a 7 June flyby of Ganymede.NASA/JPL-Caltech/SwRI/MSSS
Juno grabs glimpse of Ganymede
NASA’s Juno spacecraft has captured the first close-up images of Jupiter’s moon Ganymede in more than 20 years. Juno came within 1,038 kilometres of the world, which is bigger than Mercury. More images are on their way from the spacecraft and will allow scientists to piece together a colour version of the spectacular portrait of the Jovian satellite. “We are going to take our time before we draw any scientific conclusions, but until then we can simply marvel at this celestial wonder,” said Scott Bolton, principal investigator of the Juno mission, in a NASA statement. Bask in all the raw images as NASA makes them available on its website.
Lasers could push tiny craft to other stars
Spacecraft propelled by lasers could allow us to explore planetary systems without waiting several lifetimes. Researchers propose that around 100 million individual lasers on Earth could accelerate an ultralight spacecraft to Alpha Centauri within 20 years. The plan is another step forwards for the Starshot Breakthrough Initiatives, funded by tech billionaire Yuri Milner, which in 2018 outlined the 100-atom-thick solar sail that would also be required. “We already have several crafts — Voyager included — [in interstellar space], but it will be many human lifetimes before they reach anywhere near another star,” says astrophysicist Chathura Bandutunga.
Reference: Journal of the Optical Society of America B paper & Nature Materials paper (from 2018)
COVID-19 coronavirus update
The COVID lab-leak hypothesis
Most scientists say SARS-CoV-2 probably has a natural origin, and was transmitted from an animal to humans. However, a laboratory leak has not been ruled out, and many are calling for a deeper investigation into the hypothesis that the virus emerged from the Wuhan Institute of Virology, located in the Chinese city where the first COVID-19 cases were reported. Nature cuts through the clamour with a sober examination of the arguments for a lab leak, and the extent to which research has answers.
China vaccinates 20 million people per day
For more than a week, an average of about 20 million people have been vaccinated against COVID-19 every day in China. After a slow start, the country now accounts for more than half of the roughly 35 million people around the world who receive a COVID-19 shot each day. The majority of the doses are either CoronaVac, produced by Beijing-based company Sinovac, or the vaccine developed in Beijing by state-owned firm Sinopharm — both of which have been approved for emergency use worldwide by the World Health Organization. China’s staggering gain in manufacturing capacity could make a significant dent in global demand for vaccines. It has already supplied 350 million doses of the two vaccines to more than 75 nations.
Source: Our World in Data
Features & opinion
No cookie-cutter strategy for reproducibility
The replication crisis won’t be solved with broad brushstrokes, argues sociologist David Peterson, whose work has revealed why some scientists greet reform efforts with scepticism. Part of the problem is that many reformers come from a narrow swathe of academia, such as psychology and social and behavioural sciences. Reformers “need to demonstrate that they understand how specific fields operate before they push a set of practices”, writes Peterson. “Otherwise, efforts could be resisted as extensions of bureaucracy, rather than embraced as routes to more robust research.”
Climate-policy models need to get real
There is good news for decarbonizing the global economy: political support is at an all-time high, and most carbon emissions come from countries that have committed to reach ‘net zero’ by mid-century. But to plan how to get there, analysts use computer models that don’t recognize the difficult trade-offs faced by decision makers, argue ten climate-policy experts. They outline exactly how insights from political economy lead to 11 ways that models can better reflect social realities and possibilities.
