The top three news stories of the week, as chosen by our resident students. This week’s top stories are heavy particles, hot satellites and hued coral.

Article written by Federico Donà

3The LHCb is charmed to announce a new particle with two heavy quarks

Last week there was a new exciting discovery from the researchers at the CERN. The LHCb experiment at CERN’s Large Hadron Collider has reported the observation of Xicc++ — a new particle containing two charm quarks and one up quark. Nearly all the matter that we see around us is made of baryons, which are common particles composed of three quarks, the best-known being protons and neutrons. However, this is the first time, after years of experiments, that the existence of this particle from the baryon family was discovered. The mass of the newly identified particle is about 3621 MeV, which is almost four times heavier than the most familiar baryon, the proton, a property that arises from its doubly charmed quark content. It is the first time that such a particle has been unambiguously detected. The observation of the Ecc++ in LHCb raises the expectation of the detection of other representatives of the family of doubly heavy baryons. They will now be searched for at the LHC. So, we need to be prepared for more announcements from the CERN.

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BepiColombo: Joint Mercury mission ready for ‘pizza oven’

Two satellites that make up the BepiColombo mission to Mercury were presented to the media last Thursday. This joint European-Japanese venture has been in development for nearly two decades, but should finally get to the launch pad in 15 months’ time (yes, it has not started yet).

The two spacecraft will travel together to the baking world but separate on arrival to conduct their own studies.

In the picture, you can admire the edifice that goes on top of the rocket and comprises Europe’s Mercury Planetary Orbiter (MPO) and Japan’s Mercury Magnetospheric Orbiter (MMO), as well as the propulsion module to control their path towards the world that circles closest to the Sun.

As a single item, the stack has just finished a series of important tests, but it will shortly be taken apart so that the individual components can continue with their own preparations.

The double mission is due to blast away from Earth on an Ariane rocket in October 2018. Everyone will have to be patient, however; it is going to take seven years for the satellite duo to get to their destination.

“Mercury is the least explored of the rocky planets, but not because it is uninteresting,” said Prof Alvaro Giménez Cañete, the director of science at the European Space Agency (ESA). “It’s because it’s difficult. It’s difficult to get there; it’s even more difficult to work there.”

Both agencies are delighted to at last be approaching launch.

The launch date was repeatedly put back as engineers struggled to find equipment that could cope with the intense heat and radiation experienced just a few tens of millions of km from the Sun. The development of solar cells, in particular, proved extremely problematic. “We’re flying into a pizza oven,” quipped ESA project manager Ulrich Reininghaus. “We had to test materials at different, very high-temperature regimes, sometimes with very unwanted results.

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Get the glow: the secret to deep-water corals’ radiance.

Scientists know that in shallow waters, organisms light up green using fluorescent proteins as a kind of sun block. The proteins soak up harmful ultraviolet rays, re-emit green light and shield their symbiotic algae, which supply most of the corals’ energy needs through photosynthesis.

In 2015, a team led by Jörg Wiedenmann at the University of Southampton, UK, found that deep-dwelling corals also fluoresce, this time in an array of vivid yellows, oranges and reds.

Some of these organisms live in water as deep as 165 metres, where little sunlight reaches them, and what does is in the blue part of the spectrum. So, the researchers suspected a different reason for the glow.

Now, Wiedenmann thinks his team has the answer: the corals use a fluorescent protein to make the most of the small amount of light available in their habitats for photosynthesis. In other words, the deep-water corals and their shallow relatives fluoresce for opposite reasons.

However, says Wiedenmann, the study shows that the protein pigments expressed by shallow corals are “biochemically and optically distinct” from those of their deep-dwelling counterparts. “Not many of them may have the capacity to escape to deeper waters,” he says. “We need to make sure that reefs in shallow water stay habitable for corals.”