Aurora how does it work

The Earth's "magnet" is deep in the core. Since we can't see the magnetic field, we draw lines to represent it. The field lines go into and out of the Earth around the Earth's magnetic poles. Where the lines are closest together the field is strongest. Where they are furthest apart it is weakest. Can you tell where the magnetic field is the strongest?

Where is it weakest? What Makes Auroras Happen? To Listen to this clip you will need the RealAudio player. Main Menu Self-Guide Menu. This wind is always pushing on the Earth's magnetic field, changing its shape.

You change the shape of a soap bubble in a similar way when you blow on its surface. We call this compressed field around the earth the magnetosphere. The Earth's field is compressed on the day side, where the solar wind flows over it. It is also stretched into a long tail like the wake of a ship, which is called the magnetotail , and points away from the Sun.

The way the aurora works is a lot like a neon sign, except that in the aurora, the conducting gas is in the ionosphere, instead of a glass tube, and the current travels along magnetic field lines instead of copper wires.

Dinosaurs walked under them, just as we do today. But what are they and how are they created? For centuries, people have been sharing stories of the Northern Lights. Without scientific understanding, our ancestors were forced to fill in the gaps with fantastic stories of gods and monsters. These stories taught people to respect, fear, or worship the lights in the sky.

But as our understanding of the solar system and our place within it grew, these stories dissolved into legends and myths. These particles originate from our star - the sun. The sun is constantly pushing out a stream of electrically charged particles called the solar wind, and this travels out from the sun at between and km per second in all directions. As the Earth travels around the sun, a small fraction of particles from the solar wind are intercepted by the planet. When these charged particles hit the atoms and molecules high up in our atmosphere, they become excited.

This creates two glowing rings of auroral emission around the North and South magnetic poles, known as auroral ovals. As they decay back to their original state, they emit distinctive colours of light. NASA is also on the hunt for clues about how the northern lights work. In , the space agency launched the Parker Solar Probe , which is currently orbiting the sun and will eventually get close enough to "touch" the corona. While there, the spacecraft will collect information that could reveal more about the northern lights.

On Earth, the northern lights' counterpart in the Southern Hemisphere is the southern lights — they are physically the same and differ only in their location. As such, scientists expect them to occur simultaneously during a solar storm, but sometimes the onset of one lags behind the other. The hemispheric asymmetry of the aurora is in part due to the sun's magnetic field interfering with Earth's magnetic field, but research into the phenomenon is ongoing.

Like the northern and southern lights, STEVE is a glowing atmospheric phenomenon, but it looks slightly different from its undulating auroral counterparts. A study published in the journal Geophysical Research Letters discovered that STEVE is the result of two mechanisms: The mauve streaks are caused by the heating of charged particles in the upper atmosphere, while the picket-fence structure results from electrons falling into the atmosphere.

Auroras occur on other planets, too — all that's required to make an aurora is an atmosphere and a magnetic field. Seeing the northern lights with your own eyes is a bucket-list item for astronomy lovers and travelers alike. Fortunately, they occur frequently. But that doesn't mean they're easy to spot; you need to be at the right place at the right time.

That's where the aurora most frequently occurs, though the phenomenon can creep farther south during particularly strong solar storms. Within the zone, it's best to be as far away from city lights as possible to maximize visibility. But it's pretty tricky to get into the middle of the Arctic wilderness, even with a guide, so it's best to base yourself in a destination with solid infrastructure, like Fairbanks, Alaska; Yellowknife, Canada; Svalbard, Norway; Abisko National Park, in Sweden; Rovaniemi, Finland; and pretty much anywhere in Iceland.

Related: Where to see the northern lights: aurora borealis guide.