Magnetic Storm/ Coronal Mass Ejection

Using the suite of instruments on board Solar-B, scientists will study solar activity including coronal mass ejections. When these blast through the sun's outer atmosphere and plow toward Earth at speeds of thousands of miles per second, the resulting effects can be harmful to communication satellites and astronauts outside the Earth's magnetosphere. On the ground, the magnetic storm wrought by these solar particles can knock out electric power. A better understanding of this solar activity could give people on Earth more time to prepare by placing satellites in a safe configuration, planning the best time for astronaut space walks or rocket launches, and implementing contingency plans to deal with any power outages.
Magnetic Storm
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A geomagnetic storm is a temporary disturbance of the Earth's magnetosphere caused by a disturbance in space weather. Associated with solar coronal mass ejections (CME), coronal holes, or solar flares, a geomagnetic storm is caused by a solar wind shock wave which typically strikes the Earth's magnetic field 24 to 36 hours after the event. This only happens if the shock wave travels in a direction toward Earth. The solar wind pressure on the magnetosphere will increase or decrease depending on the Sun's activity. These solar wind pressure changes modify the electric currents in the ionosphere

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The Sun

The Sun is the star at the center of the Solar System. The Earth and other matter (including other planets, asteroids, meteoroids, comets, and dust) orbit the Sun, which by itself accounts for about 99.86% of the Solar System's mass.^[9] The mean distance of the Sun from the Earth is approximately 149.6 million kilometers (1 AU), and its light travels this distance in 8 minutes and 19 seconds. This distance varies throughout the year from a minimum of 147.1 million kilometers (0.9833 AU) on the perihelion (around 3 January), to a maximum of 152.1 million kilometers (1.017 AU) on theaphelion (around 4 July).^[10] Energy from the Sun, in the form of sunlight, supports almost all life on Earth via photosynthesis,^[11] and drives the Earth's climate and weather. The Sun consists ofhydrogen (about 74% of its mass, or 92% of its volume), helium (about 24% of mass, 7% of volume), and trace quantities of other elements, including iron, nickel, oxygen, silicon, sulfur, magnesium,carbon, neon, calcium, and chromium.

This series takes a fascinating new look at a very old universe. Fifty years after man first ventured into outer space, we examine the greatest secrets of the heavens. Each episode outlines how humans have explored the universe, and scrutinises the discoveries they have made. We look at hi-tech space telescopes which record the violent birth of stars, robotic rovers which glimpse the red surface of Mars, and sophisticated NASA probes which delve into the mysterious make-up of comets. As the earth churns ominously with the effects of global warming, this is a revealing and prescient journey into the heavens. From the planets to the stars and out to the edge of the unknown, history and science collide in this epic exploration of the Universe and its mysteries. In ‘Secrets of the Sun’, we explore the myriad mysteries which lie beneath the fiery surface of the sun. Our sun is a fireball in the sky - a bubbling, boiling, kinetic sphere of white hot plasma, exploding and erupting. Its size is almost unimaginable: one million Earths would fit within its boundaries. In this violence is born almost all the energy that makes existence on Earth possible. Yet its full mysteries are only now beginning to be understood. From sun spots to solar eclipses, solar flares to solar storms, the birth of the sun to its potential death, discover the science and history behind this celestial object that makes life on Earth possible.

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Top 5 Most Extreme Exoplanets

An extrasolar planet, or exoplanet, is a planet beyond our Solar System, orbiting a star other than our Sun. As of August 2009^[update], 373 exoplanets are listed in the Extrasolar Planets Encyclopaedia.The vast majority have been detected through radial velocity observations and other indirect methods rather than actual imaging. Most announced exoplanets are massive gas giant planets thought to resemble Jupiter, but this is a selection effect (bias) due to limitations in detection technology. Projections based on recent detections of much smaller worlds suggest that lightweight, rocky planets will eventually be found to outnumber extrasolar gas giants.

Searching for planets beyond our solar system is a bit like playing Goldilocks — we keep looking for that one that will be just right to host life. While astronomers haven’t found a perfect fit yet, they have found plenty that are too big, too hot, too cold, too dense, too close to their star, or too distant.

The first exoplanet discovery was in 1988, though it was controversial at the time and wasn’t officially confirmed until 2003. Over the years, more than 330 extrasolar planets have been found, nearly all of them using indirect methods such as detecting the wobble of a star due to the gravitational pull of an orbiting planet or the slight dimming of the star’s light as a planet passes in front of it.

Another method uses an intervening star to gravitationally magnify the light from a more distant star with planets. And in a few rare cases, the conditions are right for direct imaging of an exoplanet using a technique that allows powerful ground-based telescopes to separate the faint light of a planet from the overwhelming light of its star.

Of the planets discovered beyond our solar system to date, here are five of the most extreme:

5. CoKu Tau/4
This exoplanet, found about 420 light-years away around the star CoKu Tau 4, is one of the youngest extraterrestrial worlds discovered. Its star is thought to be only about 1 million years old, meaning its planet must be even younger. That makes it a wee young ‘un next to the grizzled Earth, which is about 4.5 billion years old. Studying baby planetlets like this could help astronomers figure out how planets are born in the first place. (Illustration, above: NASA/JPL-Caltech/R. Hurt (SSC-Caltech))

4. PSR B1620-26 b
This bizarre world, estimated to be 13 billion years old (almost three times the age of Earth), is one of the oldest known exoplanets. Its age isn’t its only weird factor, though. The gas-giant planet, which lies in the globular cluster M4, appears to be orbiting around not one, but two stars, in a binary system. Its parent stars are a small, dense white dwarf star and a quickly rotating pulsar. (Illustration: NASA and G. Bacon (STScI))

3. SWEEPS-10
This zippy planet circles its parent star at one of the fastest rates yet discovered — about once every 10 hours. It accomplishes this feat by dwelling extremely close to its star — only about 1.2 million kilometers (745,000 miles), or roughly three times the span between the Earth and the moon. At such a distance, the planet needs all of its hefty bulk (about 1.6 times the mass of Jupiter) to resist being torn apart by its star. (Illustration: NASA, ESA, A. Schaller (for STScI))

2. OGLE-2005-BLG-390Lb
In contrast to most exoplanets, which are fiery balls of gas, this globe is thought to be hard and rocky. The planet, about 5.5 times as massive as Earth, is still one of the coldest and most Earth-like planets found to date. Sadly, though, with a surface temperature of -364 degrees Fahrenheit (-220 degrees Celsius) it is probably too frigid to host life. (Illustration: NASA, ESA and G. Bacon (STScI))

1. HD 149026b
This boiling world is one of the hottest and densest ever found. None too pleasant to visit, the surface of the planet is about 3700 degrees Fahrenheit (more than 2,000 degrees Celsius) — about three times hotter than the surface of Venus, the hottest planet in our solar system. HD 149026b is so hot that scientists think it absorbs almost all of the heat from its star, and reflects almost no light. The scorching ball is smaller than Saturn, but has a core that weighs 70 to 90 times the mass of the entire Earth. (Illustration: NASA/JPL-Caltech)