Author: The Conversation

Sketchy ads, like those for miracle weight loss pills and suspicious-looking software, sometimes appear on legitimate, well-regarded websites. It turns out that most websites don’t actually decide who gets to show ads to their viewers. Instead, most sites outsource this task to a complex network of advertising tech companies that do the work of figuring out which ads are shown to each particular person. The online ad ecosystem is largely built around “programmatic advertising,” a system for placing advertisements from millions of advertisers on millions of websites. The system uses computers to automate bidding by advertisers on available ad spaces,…

Russia used a hypersonic missile against a Ukrainian arms depot in the western part of the country on March 18, 2022. That might sound scary, but the technology the Russians used is not particularly advanced. However, next-generation hypersonic missiles that Russia, China and the U.S. are developing do pose a significant threat to national and global security. I am an aerospace engineer who studies space and defense systems, including hypersonic systems. These new systems pose an important challenge due to their maneuverability all along their trajectory. Because their flight paths can change as they travel, these missiles must be tracked throughout…

An analysis of the genetic material in the ocean has identified thousands of previously unknown RNA viruses and doubled the number of phyla, or biological groups, of viruses thought to exist, according to a new study our team of researchers has published in the journal Science. RNA viruses are best known for the diseases they cause in people, ranging from the common cold to COVID-19. They also infect plants and animals important to people. These viruses carry their genetic information in RNA, rather than DNA. RNA viruses evolve at much quicker rates than DNA viruses do. While scientists have cataloged hundreds of thousands of DNA viruses in their natural ecosystems, RNA viruses have been relatively unstudied.…

Among the many changes brought about by the pandemic is the widespread use of QR codes, graphical representations of digital data that can be printed and later scanned by a smartphone or other device. QR codes have a wide range of uses that help people avoid contact with objects and close interactions with other people, including for sharing restaurant menus, email list sign-ups, car and home sales information, and checking in and out of medical and professional appointments. QR codes are a close cousin of the bar codes on product packaging that cashiers scan with infrared scanners to let the checkout computer know…

It’s not long since billionaires were competing to get to the “edge of space”. Now, the first set of private citizens are getting ready to take a SpaceX shuttle up to the International Space Station (ISS). Unlike the short “joyrides” of Richard Branson and Jeff Bezos, this mission will be reaching the roughly 400km altitude needed to dock with the ISS. The mission by the US commercial aerospace company Axiom Space is a major step forward in private space travel, and is part of a plan to build a private space station. With Russia recently pulling out of collaborating on the ISS,…

The Hubble Space Telescope has observed the most distant star ever seen – Earendel, meaning morning star. Even though Earendel is 50 times the mass of the Sun, and millions of times brighter, we would not normally be able to see it. We can see it due to an alignment of the star with a large galaxy cluster in front of it whose gravity bends the light from the star to make it brighter and more focused – essentially creating a lens. Astronomers see into the deep past when we view distant objects. Light travels at a constant speed (3×10⁸ metres per…

Measures adopted to control the spread of the COVID pandemic resulted in a worldwide reduction in economic activities. This benefited the environment by reducing pollution and greenhouse gas emissions. That said, we should not lose sight of the devastating impact the measures had on poor households. The reduction of environmental pollution has offered countries the opportunity to start from a position of reduced pollution. If sustained this should contribute to an environmentally sustainable economy in line with the United Nations Sustainable Development Goals. The lockdown has therefore offered the chance to start rebuilding from a lower emissions base. But there’s a…

Almost 400 years ago, in The Assayer, Galileo wrote: “Philosophy is written in this grand book, the universe … [But the book] is written in the language of mathematics.” He was much more than an astronomer, and this can almost be thought of as the first writing on the scientific method. We do not know who first started applying mathematics to scientific study, but it is plausible that it was the Babylonians, who used it to discover the pattern underlying eclipses, nearly 3,000 years ago. But it took 2,500 years and the invention of calculus and Newtonian physics to explain the patterns. Science Magazine looks…

If you’ve seen photos of a teapot shaped like an avocado or read a well-written article that veers off on slightly weird tangents, you may have been exposed to a new trend in artificial intelligence (AI). Machine learning systems called DALL-E, GPT and PaLM are making a splash with their incredible ability to generate creative work. DALL·E 2 is here! It can generate images from text, like “teddy bears working on new AI research on the moon in the 1980s”. It’s so fun, and sometimes beautiful.https://t.co/XZmh6WkMAS pic.twitter.com/3zOu30IqCZ — Sam Altman (@sama) April 6, 2022 These systems are known as “foundation models” and are not all hype and party…

The current flooding in South Africa’s coastal city of Durban is dire and reports indicate that hundreds of people have died and thousands directly affected. Several months’ worth of rainfall have fallen in a day or so, and the effects have been catastrophic. The problem of floods in Durban is not new. Between 1980 and 2010, there were over 77 disastrous flood events in KwaZulu-Natal province and others. The flood events can be categorised as disastrous when lives are lost, people are displaced and property is destroyed. Floods have over the years become increasingly problematic, especially in the global south, because of high population…