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Spring Equinox

Spring Equinox

Spring Equinox  will also happen on March 20. While it won’t have any discernable, direct impact on how the solar eclipse looks, it will contribute to a rare collision of three unusual celestial events.

On March 20, the Earth’s axis will be perpindecular to the sun’s rays — which only happens twice a year, at the two equinoxes. After that, it will start tipping over, making the days longer in the northern hemisphere.

As such, the equinox has long been celebrated as a time of beginning and renewal, by a number of historic cultures, and is linked to Easter and Passover.

The equinox will happen at the same time as a solar eclipse in 2053 and 2072, though it doesn’t always appear as close together as that.

The Spring Equinox marks the moment the Sun crosses the celestial equator – the imaginary line in the sky above the Earth’s equator – from south to north. This happens on March 19, 20 or 21 every year.

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That’s true no matter where you live on Earth, because the sun shines on the celestial equator – Earth’s equator projected onto the great dome of sky – as seen from everywhere around the globe.

The Spring Equinox represents a point on Earth’s orbit, but it’s also an event that happens on the imaginary dome of Earth’s sky. It marks that special moment when the sun crosses the celestial equator going from south to north. The imaginary celestial equator is a great circle dividing the imaginary celestial sphere into its northern and southern hemispheres. The celestial equator wraps the sky directly above Earth’s equator, and at this equinox, the sun crosses the celestial equator, to enter the sky’s northern hemisphere. All these components are imaginary, yet what happens at every equinox is very real – as real as the sun’s passage across the sky each day and as real as the change of the seasons.

No matter where you are on Earth (except the North and South Poles), you have a due east and due west point on your horizon. That point marks the intersection of your horizon with the celestial equator – the imaginary line above the true equator of the Earth.

At the equinoxes, the sun appears overhead at noon as seen from Earth’s equator, as the illustration at left shows. This illustration (which is by Tau’olunga) shows the sun’s location on the celestial equator, every hour, on the day of the equinox.

That’s why the sun rises due east and sets due west for all of us. The sun is on the celestial equator, and the celestial equator intersects all of our horizons at points due east and due west.

This fact makes the day of an equinox a good day for finding due east and due west from your yard or other favorite site for watching the sky. Just go outside around sunset or sunrise and notice the location of the sun on the horizon with respect to familiar landmarks.

If you do this, you’ll be able to use those landmarks to find those cardinal directions in the weeks and months ahead, long after Earth has moved on in its orbit around the sun, carrying the sunrise and sunset points northward.
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New Planet Is Earth’s Twin 200 Light Years Away

New Planet Is Earth’s Twin 200 Light Years Away

New Planet Is Earth’s Twin 200 Light Years Away. The planet, known as KOI-314c, is the same weight as Earth but much larger and has a surface temperature of 104C.

New Planet Is Earth’s Twin 200 Light Years away and scientists have stumbled upon a planet considered Earth’s ‘twin’ in another solar system 200 light years away.

Known as KOI-314c, the planet is the same weight as Earth but 60% larger.

The planet is also much hotter than Earth, with scientists estimating its surface temperatures to be around 104 degC – unsupportive of most life forms on Earth.

KOI-314c is suspected to have a thick gaseous atmosphere, making the planet only 30% denser than water.

However, despite a similar weight, astronomers said the planet is not considered “Earth-like”.

“This planet might have the same mass as Earth, but it is certainly not Earth-like,” said lead astronomer Dr David Kipping, from the Harvard-Smithsonian Centre for Astrophysics in the US.

He added: “It proves that there is no clear dividing line between rocky worlds like Earth and fluffier planets like water worlds or gas giants.”

Scientists made the discovery by accident while searching for moons using the powerful Kepler space telescope.

“When we noticed this planet showed transit timing variations, the signature was clearly due to the other planet in the system and not a moon,” said Dr Kipping.

He said: “At first we were disappointed it wasn’t a moon, but then we soon realised it was an extraordinary measurement.”

Evidence of the new planet was presented at the annual meeting of the American Astronomical Society in Washington DC.
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Met Office To Launch Round The Clock Space Weather Forecasting

Met Office To Launch Round The Clock Space Weather Forecasting

Met Office To Launch Round The Clock Space Weather Forecasting Service. The UK government is launching a round-the-clock space weather forecasting system in partnership with the Met Office, which will make the country one of a just a handful monitoring the weather between Earth’s atmosphere and the Sun.

The service will be run by the Met Office thanks to a £4.6 million investment by the Department for Business Innovation and Skills, and will aim to protect national infrastructure. It equals to approximately one thousandth of the science budget, although it is being drawn from a separate pool of money, said Science Minister David Willetts, speaking at a press conference.

Space forecasts will start in spring 2014, but it will be autumn before the service is operating fully. The money will primarily be spent on the forecast bench, as well as a team of people that will collaborate with academia to make sure the latest research and knowledge is being properly relayed to the forecasters. Phil Evans from the Met Office claims the system will be cost effective as it will rely on pre-existing infrastructure, including the European Space Agency’s Solar Orbiter, which will take us closer to the sun than we’ve ever been before.

The main aim of the service is to offer UK-centric advice, but it will also be part of a larger international effort. The US already has its own space weather monitoring service, but has approached the UK to try and combine efforts. The Met Office will be working with external partners including the British Antarctic Survey and NoAA Space Weather Prediction Centre, in the hope that the forecasting service will be able to benefit a wide range of sectors, as well as potentially be commercialised.

What are the risks posed by space weather?

Space weather is a term that is used to refer to the changing environmental conditions between Earth and the Sun. While the Sun is constantly giving off bursts of energy, some of these bursts pose greater risks than others.

Solar flares, for example, can cause HF radio blackouts, and because they only take about 8.5 minutes to arrive in Earth’s atmosphere, they are very hard to see coming. Radiation storms, on the other hand, take between ten minutes and an hour to arrive and so have a greater chance of being detected ahead of time. They can cause radiation damage to astronauts and airline passengers over the polar regions, meaning that if airlines are forewarned they can redirect planes and make allowances for longer flight times.

More serious, however, are CME large plasma bubbles, which cause geomagnetic storms (and the Aurora, as it happens) that can impact electricity grids and disrupt the ionosphere, although they are quite easy to predict given that they take between 17 hours and 39 days to arrive.

In 2011 the government put space weather on the national risk register. The reason that the risks posed by space weather are increasing are due to our increasing reliance on technology, including GPS, that could potentially be affected by the effects of that weather.

“We’ve got more systems out there that might be vulnerable to space weather than ever before,” says David Willets. “This is the right time to be investing in space weather technology.”

What the government really fears is another “Carrington Event”, which was a solar storm that occurred in 1989. Astronomer Richard Carrington observed an almighty eruption from the sun’s surface that spewed a huge solar flare. It caused an aurora that was seen as far south as Hawaii and Chile, but in today’s technology-dependent world it could cause billions of pounds worth of damage. There is a 12 percent chance that another such event could occur within the next decade.

We are currently at solar maximum, and while this means there is more solar activity in general, the largest events don’t tend to cluster around the max — they could happen at any time.

The whole point of the system is to get warning out to businesses and organisations ahead of time, in order that they can put in place contingency plans to minimise disruption. One example given by Mark Gibbs of the Met Office was the National Grid, which could stop planned maintenance and make sure the backup service was switched on. “The more of the equipment you have working, the more you can spread the load,” he says.

The biggest concern is that the transformers could get knocked out, because it take a long time to restore them, he explains, but adds that the UK’s National Grid infrastructure is very well reinforced and far less susceptible to this kind of occurrence than the system in the US.

“A round-the-clock UK forecasting service for space weather is essential as part of National Grid’s procedures for running the electricity transmission network securely and safely. It is great news for National Grid that the Met Office has secured funding for its space weather forecasting operations,” said Andrew Richards, a risk and resilience analyst for National Grid, in a statement.

While the service is primarily concerned with these very extreme events, it will also be collecting information about smaller day-to-day occurrences too. If you’re finding all this talk of space weather a bit unnerving, please do check out the Wired UK guide to surviving a solar storm.
SOURCE FROM
http://www.wired.co.uk/
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