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After more than 30 years of traveling through the cosmos, a far-flung NASA spacecraft has entered an uncharted region between our solar system and interstellar space, scientists announced Monday.

Data received from the probe indicate that it is still within the so-called heliosphere, which is a large bubble of solar plasma and solar magnetic fields that the sun blows around itself. At the perimeter of the heliosphere is the heliosheath, a turbulent region at the outer edge of the solar system.

“Newton tells us the spacecraft will reach interstellar space,” Stone said. “The question is, will we still be transmitting when that happens? No spacecraft has ever been there before. We continue to find our models need to be improved as we learn more about the complex interaction between solar wind and interstellar wind. The transition may not be instantaneous. There may be a turbulent interface, (and it) may take us months to get through a rather messy interface between these two winds.”

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NASA’s Voyager probes are truly going where no one has gone before. Gliding silently toward the stars, 9 billion miles from Earth, they are beaming back news from the most distant, unexplored reaches of the solar system.

Mission scientists say the probes have just sent back some very big news indeed.

It’s bubbly out there.

According to computer models, the bubbles are large, about 100 million miles wide, so it would take the speedy probes weeks to cross just one of them. Voyager 1 entered the “foam-zone” around 2007, and Voyager 2 followed about a year later. At first researchers didn’t understand what the Voyagers were sensing–but now they have a good idea.

“The sun’s magnetic field extends all the way to the edge of the solar system,” explains Opher. “Because the sun spins, its magnetic field becomes twisted and wrinkled, a bit like a ballerina’s skirt. Far, far away from the sun, where the Voyagers are now, the folds of the skirt bunch up.”

When a magnetic field gets severely folded like this, interesting things can happen. Lines of magnetic force criss-cross, and “reconnect”. (Magnetic reconnection is the same energetic process underlying solar flares.) The crowded folds of the skirt reorganize themselves, sometimes explosively, into foamy magnetic bubbles.

“We never expected to find such a foam at the edge of the solar system, but there it is!” says Opher’s colleague, University of Maryland physicist Jim Drake.

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First ‘habitable’ exoplanet confirmed

PARIS: A rocky world orbiting a nearby star was confirmed as the first planet outside our Solar System to meet key requirements for sustaining life.

Modelling of planet Gliese 581d shows it has the potential to be warm and wet enough to nurture Earth-like life, scientists have said. It orbits a red dwarf star called Gliese 581, located around 20 light years from Earth, which makes it one of our closest neighbours.

Gliese 581d orbits on the outer fringes of the star’s ‘Goldilocks zone’, where it is not so hot that water boils away, nor so cold that water is perpetually frozen. Instead, the temperature is just right for water to exist in liquid form.

Zarmina’s World

“With a dense carbon dioxide atmosphere – a likely scenario on such a large planet – the climate of Gliese 581d is not only stable against collapse but warm enough to have oceans, clouds and rainfall,” France’s National Centre for Scientific Research (CNRS) said.

More than 500 planets orbiting other stars have been recorded since 1995, detected mostly by a tiny wobble in stellar light. Exoplanets are named after their star and listed alphabetically, in order of discovery.

Until now, the big interest in Gliese 581’s roster of planets focussed on Gliese 581g. It leapt into the headlines last year as ‘Zarmina’s World’, after its observers announced it had roughly the same mass as Earth’s and was also close to the Goldilocks zone.

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In order to detect signs of past or present life on Mars — if it is in fact true that we’re related — then a promising strategy would be to search for DNA or RNA, and specifically for particular sequences of these molecules that are nearly universal in all forms of terrestrial life. That’s the strategy being pursued by MIT research scientist Christopher Carr and postdoctoral associate Clarissa Lui, working with Maria Zuber, head of MIT’s Department of Earth, Atmospheric and Planetary Sciences (EAPS), and Gary Ruvkun, a molecular biologist at the Massachusetts General Hospital and Harvard University, who came up with the instrument concept and put together the initial team. Lui presented a summary of their proposed instrument, called the Search for Extra-Terrestrial Genomes (SETG), at the IEEE Aerospace Conference this month in Big Sky, Mont.

The idea is based on several facts that have now been well established. First, in the early days of the solar system, the climates on Mars and the Earth were much more similar than they are now, so life that took hold on one planet could presumably have survived on the other. Second, an estimated one billion tons of rock have traveled from Mars to Earth, blasted loose by asteroid impacts and then traveling through interplanetary space before striking Earth’s surface. Third, microbes have been shown to be capable of surviving the initial shock of such an impact, and there is some evidence they could also survive the thousands of years of transit through space before arriving at another planet.

17th-century British scientist Robert Boyle was many things: the father of modern chemistry, a founding member of the Royal Society, an inventor, the discoverer of the eponymous gas law, an alchemist, an experimenter on his own body fluids, and a friend to necromancers who offered him sex with demons. Now we can add “clairvoyant” to that colourful list.

Last week the Royal Society displayed for the first time a remarkable document: Boyle’s 24-point wish list for the future of science.

The list, which dates back to the 1660s, was found among his private papers and predicts the inventions of GPS navigation, flight, organ transplants, commercial agriculture and hair dye, among other things.

We were inspired and began to wonder, what could the next 400 years hold? So we asked several of today’s prominent scientists to emulate Boyle and write their own wish lists.

David Eagleman, neuroscientist and fiction writer

  • Download consciousness into a computer to live forever;
  • Travel to extra-solar planets in a reasonable amount of time;
  • Determine how to get by on zero sleep.

Steve Jones, geneticist

  • Understand the science of human emotions broadly enough to put an end to war;
  • A universal abandonment of religious belief as science triumphs over myth;
  • A healthy old age followed by an instant death;
  • The end of the need for grief;
  • The ability to grow fingers as well as we can fingernails;
  • An insight into why snails vary so much genetically from place to place.

Sean Carroll, physicist

  • Understand dark matter and dark energy, which together comprise 96 per cent of our universe;
  • Understand consciousness and intelligence, so that we could mimic it in computers.

Seth Shostak, SETI astronomer.

  • Discover not only abundant biology throughout the cosmos, but at least one instance of extraterrestrial intelligence within the next 100 years;
  • Invent regenerative therapies to cure problems related to aging such as hearing and vision loss and the degeneration of skin tone;
  • A population ten times that of Earth now living in orbiting space colonies within 200 years;
  • The ability to control local climate and alter Earth’s topography.

Jim Al-Khalili, physicist and broadcaster.

  • The convergence of nanoscience and biology enabling nano-robotic surgery and drug delivery to specific locations within cells in the body;
  • Learn whether string theory really lives up to its promise of being a “theory of everything”;.
    The realisation of a true quantum computer;
  • Crack the mystery of life itself: discover how something so unlikely could have emerged by chance on Earth three and a half billion years ago.

Lastly, here are a few of Boyle’s original suggestions: some have come true, while some we’re still holding our breath for:

  • The Prolongation of Life;
  • The Recovery of Youth, or at least some of the Marks of it, as new Teeth, new Hair colour’d as in youth;
  • The Art of Continuing long under water, and exercising functions freely there;
  • The Cure of Wounds at a Distance;
  • The Cure of Diseases at a distance or at least by Transplantation;
  • The Attaining Gigantick Dimensions;
  • The Emulating of Fish without Engines by Custome and Education only;
  • The Acceleration of the Production of things out of Seed;
  • Freedom from Necessity of much Sleeping exemplify’d by the Operations of Tea and what happens in Mad-Men.

The Sun is the dimmest it has been for nearly a century.

There are no sunspots, very few solar flares – and our nearest star is the quietest it has been for a very long time.

The observations are baffling astronomers, who are due to study new pictures of the Sun, taken from space, at the UK National Astronomy Meeting.

The Sun normally undergoes an 11-year cycle of activity. At its peak, it has a tumultuous boiling atmosphere that spits out flares and planet-sized chunks of super-hot gas. This is followed by a calmer period.

Last year, it was expected that it would have been hotting up after a quiet spell. But instead it hit a 50-year low in solar wind pressure, a 55-year low in radio emissions, and a 100-year low in sunspot activity.

According to Prof Louise Hara of University College London, it is unclear why this is happening or when the Sun is likely to become more active again.

“There’s no sign of us coming out of it yet,” she told BBC News.

“At the moment, there are scientific papers coming out suggesting that we’ll be going into a normal period of activity soon.

“Others are suggesting we’ll be going into another minimum period – this is a big scientific debate at the moment.”

In the mid-17th Century, a quiet spell – known as the Maunder Minimum – lasted 70 years, and led to a “mini ice age”.

This has resulted in some people suggesting that a similar cooling might offset the impact of climate change.

According to Prof Mike Lockwood of Southampton University, this view is too simplistic.

“I wish the Sun was coming to our aid but, unfortunately, the data shows that is not the case,” he said.

Prof Lockwood was one of the first researchers to show that the Sun’s activity has been gradually decreasing since 1985, yet overall global temperatures have continued to rise.

“If you look carefully at the observations, it’s pretty clear that the underlying level of the Sun peaked at about 1985 and what we are seeing is a continuation of a downward trend (in solar activity) that’s been going on for a couple of decades.

“If the Sun’s dimming were to have a cooling effect, we’d have seen it by now.”

‘Middle ground’

Evidence from tree trunks and ice cores suggest that the Sun is calming down after an unusually high point in its activity.

Professor Lockwood believes that as well as the Sun’s 11-year cycle, there is an underlying solar oscillation lasting hundreds of years.

He suggests that 1985 marked the “grand maximum” in this long-term cycle and the Maunder Minimum marked its low point.

“We are re-entering the middle ground after a period which has seen the Sun in its top 10% of activity,” said Professor Lockwood.

“We would expect it to be more than 100 years before we get down to the levels of the Maunder Minimum.”

He added that the current slight dimming of the Sun was not going to reverse the rise in global temperatures caused by the burning of fossil fuels.

“What we are seeing is consistent with a global temperature rise, not that the Sun is coming to our aid.”

Data from the Intergovernmental Panel on Climate Change (IPCC) shows global average temperatures have risen by about 0.7C since the beginning of the 20th Century.

And the IPCC projects that the world will continue to warm, with temperatures expected to rise between 1.8C and 4C by the end of the century.

No-one knows how the centuries-long waxing and waning of the Sun works. However, astronomers now have space telescopes studying the Sun in detail.

According to Prof Richard Harrison of the Rutherford Appleton Laboratory, Oxfordshire, this current quiet period gives astronomers a unique opportunity.

“This is very exciting because as astronomers we’ve never seen anything like this before in our lifetimes,” he said.

“We have spacecraft up there to study the Sun in phenomenal detail. With these telescopes we can study this minimum of activity in a way that we could not have done so in the past.”

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