A male squid’s birthday influences its mating behaviour
Forget star signs, the date a male spear quid hatches determines which mating tactic he uses throughout his life.
Japanese researchers studying the squid species Heterololigo bleekeri found male individuals that hatch earlier in the season (between early April and mid-July) become “consorts”. These squid fight off rivals to place their sperm inside a female and then guard her while she lays her eggs.
Squids that hatch later, between early June and mid-August, become smaller “sneakers”. These squid steal mating opportunities by covertly depositing their sperm on the outside of a female, near where she lays her eggs, in the hope of fertilising them.
“The difference in hatch date means that the squid experience different environmental conditions in early life, which may influence the growth trajectory,” says study co-author Yoko Iwata from the Atmosphere and Ocean Research Institute at the University of Tokyo.
Hubble celebrates 34th anniversary with new photo
Wednesday 24 April marked 34 years since the launch of NASA’s Hubble Space Telescope. Hubble has made 1.6 million observations of over 53,000 astronomical objects since its launch in 1990.
In celebration, astronomers took a photo of the Little Dumbbell Nebula, also known as Messier 76.
M76 is classified as a planetary nebula, which is an expanding shell of glowing gases that were ejected from a dying red giant star. The star is collapsing to form a white dwarf, which can be seen as a pinpoint in the centre of the nebula.
The nebula is located 3,400 light-years away in the northern circumpolar constellation Perseus.
Researchers uncover a “kinky” new alloy
US materials scientists have discovered a metal alloy that resists cracking at extreme temperatures. The unique properties are due to kinking, or bending, of crystals in the alloy at the atomic level.
The alloy is from a new class of metals known as refractory high or medium entropy alloys, which are made by mixing near-equal quantities of metallic elements with very high melting temperatures. This one is composed of niobium, tantalum, titanium, and hafnium.
Electron microscopy revealed its unusual toughness comes from a side-effect of a rare defect called a kink band.
“We show, for the first time, that in the presence of a sharp crack between atoms, kink bands actually resist the propagation of a crack by distributing damage away from it, preventing fracture and leading to extraordinarily high fracture toughness,” says David Cook, a PhD student at Lawrence Berkeley National Laboratory in the US and first author of a paper detailing the discovery in the journal Science.
“We have exhausted the ability to further optimise the materials we currently use at high temperatures, and there’s a big need for novel metallic materials. That’s what this alloy shows promise in.”
Recent eclipse sheds new light on the Sun’s corona
Citizen scientists involved in the Citizen Continental-America Telescopic Eclipse (CATE) 2024 experiment have collected unique solar data from the total eclipse that crossed the US on April 8.
Total solar eclipses offer unique opportunities to study the hot atmosphere above the Sun’s surface. More than 200 community participants were involved in an attempt to provide 60 continuous minutes of totality images with a network of 35 telescopes.
“The Citizen CATE 2024 telescopes have a polarising filter baked onto every pixel of the sensor, allowing us to measure four different angles of polarisation everywhere in the corona, providing a lot more information than just measuring the brightness of the light,” says principal investigator Dr Amir Caspi, a solar physicist at Southwest Research Institute.
Caspi also led a nearly simultaneous investigation to observe the corona using visible light and infrared imagers installed in NASA’s WB-57F research aircraft.
