Heavy metal stars, volcanic menace and a microwave mystery

A mysterious ring of microwaves

Some 50 years ago, astronomers discovered a mysterious structure that covers a third of the sky and called it Loop I.

Today, how this giant celestial mystery formed is still not fully solved, but thanks to the European Space Agency’s Planck satellite, we now have the best image of it. 

Estimates to the centre of the spherical bubble vary from 400 to 25,000 light-years because astronomers don’t know how close it is to us.

What astronomers do know is Loop I shows up in many different wavelengths, from radio waves to gamma rays.  Planck captured this image using microwaves and the colours reflect polarisation – the direction in which the microwaves are oscillating.

Integrated circuits etched on silicon

Crammed together on a single piece of silicon, 35 replicas of five different space chips are etched onto this 20-centimetre wafer. Each chip is designed by different companies and destined for multiple projects.

They incorporate up to about 10 million transistors or basic circuit switches to give Europe’s space missions the ability to perform various specialised tasks such as data handling, communications processing or attitude control.

With high fabrication costs, cramming the various chips onto the same silicon wafer saves money.

Once tested for functionality, the chips on the wafer are chopped up and packaged for use, then mounted on printed circuit boards for connection with other components.

Protecting our oceans

Across our blue planet on 8 June, the United Nations celebrated the ocean, its importance in our lives and how to protect it.

“Healthy oceans, healthy planet” raised awareness of the devastating impact plastic debris has on wildlife, climate and health.

Marine plastics are distributed throughout the ocean, from the Arctic all the way to the Antarctic, from the surface to the ocean floor.

Around four to 12 million tonnes of plastic is dumped into the ocean each year. Plastic doesn’t decompose completely but it does break into millimetre-sized particles called microplastics. Animals mistake microplastics for food, which doesn’t just affect their health, but also ours, scientists fear.

A satellite eye on Mount Ruapehu

On a busy day in winter, you can find thousands of people skiing the slopes of Mount Ruapehu, a 2,797-metre peak on New Zealand’s North Island.

Skiers and snowboarders on Ruapehu have the usual hazards, but they also have another, less-common threat to contend with – that a lahar, a river of liquefied ash and mud, may come streaming down the mountain behind them.

One of the most active volcanoes in New Zealand, Mount Ruapehu has erupted 66 times in the past 10,000 years or so, according to the Global Volcanism Program.

The threat of lahars, combined with the large numbers of people regularly using the mountain, has prompted geologists to monitor Ruapehu for signs of unrest. Scientists frequently look for signs of impending activity and satellites such as the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) offer them another perspective. They can detect thermal infrared wavelengths and observe volcanoes on the verge of erupting.

Hubble rocks with a heavy metal home

The 10.5-billion-year-old globular cluster NGC 6496 is home to heavy metal stars of a celestial kind! It is filled with stars enriched with much higher proportions of metals (elements heavier than hydrogen and helium) than stars found in similar clusters.

Residing about 35,000 light-years away in the southern constellation of Scorpius (The Scorpion), NGC 6496 hosts a selection of long-period variables — giant pulsating stars whose brightness can take up to, and even over, 1,000 days to change — and short-period eclipsing binaries, which dim when eclipsed by a stellar companion.

The nature of the variability of these stars can reveal important information about their mass, radius, luminosity, temperature, composition and evolution, providing astronomers measurements that would be difficult or even impossible to obtain through other methods.