Auroras, also known as northern lights or southern lights, are visible in the polar regions and are caused by emissions of photons in the Earth's upper atmosphere from oxygen and nitrogen. Auroras form when charged particles from the sun enter the Earth's magnetic field, accelerating particles that collide with atmospheric gases and emit colorful glows. They typically appear as diffuse glows or curtains aligned with the Earth's magnetic field lines. Auroras have also been observed on other planets like Jupiter and Saturn.

1. Aurora Borealis Made by Riquette Mory01

2. A u r o r a sAuroras are called also northern and southern (polar) lights or Aurora.Auroras are observed at night in the polar regions.Auroras are called after the Greek goddess of dawn Aurora.Auroras are most visible closer to the poles due to the longer periods of darkness and the magnetic field.The aurora australis (Latin word for “of the south”) the southern polar lights are the counterpart of the northern lights. They are visible only from high southern latitudes in Antarctica andSouth America.02November 24, 20092Aurora Borealis Riquette Mory

3. A u r o r a sAuroras are the result of the emissions of photons in the Earth's upperatmosphere:oxygenemissions Green or brownish-red, depending on the amount of energy absorbed. Nitrogenemissions Blue or red. Blue if the atom regains an electron after it has been ionized. Red if returning to ground state from an excited state. November 24, 20093Aurora Borealis Riquette Mory

4. A u r o r a sNorthern LightsSouthern LightsA predominantly red aurora australis03 AuroraBorealis Aurora australis 1994 from Bluff, New ZealandAurora australis (September 11, 2005) as captured by NASA's IMAGE satelliteNovember 24, 20094Aurora Borealis Riquette Mory

5. A u r o r a sAuroras are formed When a "solar wind" of charged particles from the Sun enters Earth's magnetic field, accelerating electrically charged particles trapped within. The high-speed particles then crash into Earth's upper atmosphere over the Polar Regions, causing the atmosphere to emit a ghostly, multicolored glow. 04November 24, 20095Aurora Borealis Riquette Mory

6. November 24, 20096Aurora Borealis Riquette MoryA u r o r a sForms and magnetismTypically the aurora appears either as a diffuse glow or as "curtains" that approximately extend in the east-west direction. Some times, they form "quiet arcs"; or sometimes ("active aurora"),“Each curtain consists of many parallel rays, each lined up with the local direction of the magnetic field lines, suggesting that aurora is shaped by Earth's magnetic field. Indeed, satellites show electrons to be guided by magnetic field lines, spiraling around them while moving towards Earth.”Northern lights over Calgary

7. November 24, 20097Aurora Borealis Riquette MoryA u r o r a sOn other planets“Jupiter aurora. The bright spot at far left is the end of field line to Io; spots at bottom lead to Ganymede and Europa.”“Both Jupiter and Saturn have magnetic fields much stronger than Earth's (Jupiter's equatorial field strength is 4.3 gauss, compared to 0.3 gauss for Earth), and both have large radiation belts.” Aurora has been observed on Jupiter and Saturn, Uranus and Neptune, most clearly with the Hubble Space Telescope.

8. On Oct. 30th, the interplanetary magnetic field (IMF) near Earth tilted south, an orientation that weakens our planet's magnetic defenses against solar wind. Solar wind poured into Earth's magnetosphere and sparked an early Halloween display of Northern Lights over Alaska.November 24, 2009Aurora Borealis Riquette Mory8A u r o r a sNiels Giroud, Nordland, Norway Oct. 24, 2009Wioleta Zarzycka, IcelandOct. 25, 2009Michael H Davies, Canada Oct. 27, 2009

9. A u r o r a sThe deepest solar minimum in nearly 100 years has not put a stop to Northern Lights around the Arctic Circle. The geomagnetic field has been quite active this month (Nov. 09),Producingdisplays of particular beauty over Scandinavia.November 24, 20099Aurora Borealis Riquette MoryTom Roland, NorwayNov. 10, 2009John, Fairbanks, AlaskaNov. 8, 2009Babak Tafreshi, NorwayNov. 7, 2009

10. Frequency of OccurrenceNovember 24, 200910Aurora Borealis Riquette MoryGeomagnetic storms that ignite auroras actually happen more often during the months around the equinoxes.It is known that during spring and autumn, the interplanetary magnetic field and that of Earth link up.I hope that you enjoyed the Aurora Borealis Beauty