麻豆传媒

Space oddity

SHMUEL Bialy and Avi Loeb at Harvard University have come up with a novel explanation for the origin of 鈥極umuamua, the interstellar object seen passing through our solar system in October 2017.

They calculate that it may not be shaped like a lumpy asteroid or comet, but instead be flat and wide. If it is a big sheet, it could behave like a light sail, which could account for apparent anomalies in its trajectory.

But the researchers aren鈥檛 just suggesting it has a strange shape. 鈥溾�極umuamua may be a fully operational probe sent intentionally to Earth vicinity by an alien civilisation,鈥� they write in , posted on the arXiv preprint server.

It鈥檚 too late to take new pictures of 鈥極umuamua, so there is no way to say for sure that the interstellar object wasn鈥檛 aliens. But we also can鈥檛 say for sure that it wasn鈥檛 a blue whale, a large piece of cheese鈥� or an asteroid.

Space oddity

PERHAPS we could do more to make contact with life elsewhere in the galaxy. James Clark, a graduate student at the Massachusetts Institute of Technology, calculates that a 1 to 2-megawatt laser, focused through a massive telescope, would produce a beam of light that would stand out like a 鈥減lanetary porch light鈥�, visible from 20,000 light years away.

鈥溾�漃lease be aware you can鈥檛 bring any real or replica bombs鈥� on board.鈥� Train firm Eurostar issues a helpful reminder to those travelling for first world war commemorations in France鈥�

Clark admits that the plan has some safety risks. The beam would damage the vision of anyone who looked at it, and might scramble cameras on spacecraft that pass through it. 鈥淚n general, this was a feasibility study,鈥� he said in a . 鈥淲hether or not this is a good idea, that鈥檚 a discussion for future work.鈥�

For more existentially pressing reasons, Feedback hopes the project goes no further. As sci-fi author Cixin Liu pointed out in a recent interview with 麻豆传媒 (8 September, p 42), 鈥渨e simply don鈥檛 know whether we are talking to friends or enemies鈥�.

Unappetizing exhibit

SPICY rabbit heads, fruit bat soup and cheese riddled with insect larvae are among the exhibits on show at the Disgusting Food Museum, which opened on 31 October in Malmo, Sweden. The idea is to challenge visitors鈥� notions of disgust, and encourage them to be open-minded about foods from other cultures.

The most offensive of the lot, according to curator Samuel West, is an Icelandic fermented shark. 鈥淚t tastes like chewing on a urine-infested mattress,鈥� he told Reuters. The museum is well prepared in case any of the exhibits prove too much for some visitors: the entrance tickets are printed on vomit bags.

Pocket pebbles

IT WAS foolish of us to hope that the $145,000 fine levied on Gwyneth Paltrow鈥檚 Goop brand for misleading claims about rose quartz and jade eggs (27 October) would curb the spread of crystal healing fruitloopery. On 4 November, the UK鈥檚 Daily Mail newspaper chimed in with a guide to improving your health and furthering your career with the help of shiny minerals.

According to crystal healer and reiki master Tamara Driessen, 鈥渃itrine will cheer you on as you pluck up the courage to ask for a pay rise鈥�, while 鈥渂lack tourmaline will protect you from draining work politics鈥�.

This is reassuring for anyone concerned about the young children working in industrial mines in the Democratic Republic of the Congo, where many of these stones are sourced. Presumably there are enough crystals in the mines to neutralise any tiresome political troubles.

Return to sender!

HOW many mosquitoes can you fit in an envelope? This isn鈥檛 a joke 鈥� scientists need to know so they can post live, sterile mosquitoes around the world in an effort to eradicate the disease-carrying insects.

As readers might have discovered themselves, mosquitoes are remarkably resistant to being squashed. By packing them into a syringe, Hae-Na Chung at New Mexico State University and her colleagues found that 240 mosquitoes can survive being compressed into . That is equivalent to 1200 mosquitoes in a teaspoon. Or 6.6 billion in a phone box. Don鈥檛 have nightmares.

Dead certain

GENETIC tests are sometimes treated as infallible, but a report from Kazakhstan reminds us they are anything but. Aigali Supugaliev was reported missing on 9 July. Two months later, a DNA test determined that a decomposed corpse found near his home was 99.92 per cent likely to be the missing man, based on a comparison with his nail clippings.

Some time after his funeral, Supugaliev reappeared, alive and well. He had taken a job on a distant farm without telling his family. Upon seeing him, his niece 鈥渁lmost collapsed with a heart attack鈥�, his brother told .

The scientist that carried out the test insists the forensics institute he works for isn鈥檛 responsible for the family鈥檚 misunderstanding. 鈥淚t is impossible to state unequivocally that this is the body of a person, relying only on the results of the DNA examination,鈥� said Akmaral Zhubatyrova . 鈥淲e should not forget about the remaining 0.08 per cent.鈥�

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