The effects predicted by Einstein’s general relativity on the motion of a star passing through the extreme gravitational field have been validated near the supermassive black hole in the center of the Milky Way.
Obscured by thick clouds of absorbing dust, the closest supermassive black hole to the Earth lies 26 000 light-years away at the centre of the Milky Way. This gravitational monster, which has a mass four million times that of the Sun, is surrounded by a small group of stars orbiting around it at high speed. This extreme environment — the strongest gravitational field in our galaxy — makes it the perfect place to explore gravitational physics, and particularly to test Einstein’s general theory of relativity.

[Eleni Petrakou, Ph.D., is a physicist and an independent researcher, besides being a longtime follower of this blog. She now has a newsletter of her own; it is high S/N stuff - check it out here. After a past collaboration with the CMS experiment, she has recently become intrigued with the dynamics of the Sun, and she developed a model to try and predict the solar cycle, a 11-year variation of the activity of sunspots and solar flares whose origin is still debated. I asked her to describe the matter for this blog, and the text below is the result - TD]


DESCRIBING THE SOLAR CYCLE

The United Nations Educational, Scientific and Cultural Organization (UNESCO) branch of the United Nations has added 24 new sites to the World Network of Biosphere Reserves, bring the total number to 686.
Biosphere reserves are sites hoping to couple conservation of biodiversity and human activity by promoting use of natural resources - which is a fuzzy term for fuzzy sustainable development practices.
The new biosphere reserves are (in alphabetical order of countries):

While cats are generally regarded as being aloof and uncaring, dogs are called "man's best friend." They are in tune with our emotions, it is said. "Lassie" had a level of connection with her humans that only television could write, but there has always been anecdotal evidence that dogs will do whatever they can to help.

A new experiment shows that not only do dogs care if their owner is upset, they will overcome obstacles in a hurry to provide aid. The results in Learning&Behavior showed that dogs with strong bonds to their owners hurried to pushed through a door when they heard their person crying. 

Millions of Americans head outdoors in the summer, whether for a day at a nearby lake or a monthlong road trip. For environmental economists like me, decisions by vacationers and outdoor recreators offer clues to a challenging puzzle: estimating what environmental resources are worth.

In 1981 President Ronald Reagan issued an executive order that required federal agencies to weigh the costs and benefits of proposed major new regulations, and in most cases to adopt them only if the benefits to society outweighed the costs. Reagan’s order was intended to promote environmental improvements without overburdening economic growth.

The moon is just a big rock in Earth's orbit now but things could have gone a lot differently in the distant past. In fact, there may have been two early windows of habitability for Luna.

In a new paper, astrobiologists say conditions on the lunar surface were sufficient to support simple lifeforms shortly after the moon formed from a debris disk 4 billion years ago and again during a peak in lunar volcanic activity around 3.5 billion years ago. During both periods, planetary scientists think the moon was spewing out large quantities of superheated volatile gases, including water vapor, from its interior.

If you are up for a job, and four other candidates are weak, your chances are obviously better than if four other candidates are strong. In the World Cup just completed, statistically there will always be a 'Group of Death", wherein a round-robin group will have three strong teams but only two can advance, meaning a world-class squad will be eliminated. 

Poker players know to bet low when the odds are only modestly better and to bet high when the statistics show the cards in hand are strong. Timing matters, in jobs, in games, in lots of things. 

Wrinkles and hair loss are perfectly natural aspects of aging - but science is all about defeating the nature that wants to kill us off.

One aspect of aging is a decline in mitochondrial function.

I had what seemed like rather a good idea a few weeks back. Building on some prominent findings in social psychology, I hypothesized that politicians on the right would wipe their bum with their left hand; and that politicians on the left would wipe with their right hand.

Ludicrous? Yes – absolutely. But for once my goal wasn’t to run a bona fide scientific study. Instead, I wanted to see if any “journal” would publish my ass-wiping “findings”.

Paracelsus famously noted Sola dosis facit venenum - "Only the dose makes the poison."