Welcome!!
This web page displays dynamic modeling of the Earth's bow shock and magnetopause.
Real time data from the ACE spacecraft (top two panels) are used to predict the shape and location of these boundaries at the present time and into the near future (The time is Universal Time as measured at Greenwich, England. Click here for information on conversions to local time).
In the figure to the right, the Earth is in the center, and is illuminated from the left by the Sun (not shown). In this view, we are looking down upon the North pole; thus the figure represents the equatorial plane. The solar wind emanating from the Sun is super-magnetosonic with respect to the Earth, so that a shock wave is formed. As the solar wind flows through the shock it is slowed down, and the pressure of the solar wind is balanced by the pressure from the Earth's magnetic field. The boundary at which this pressure balance is achieved is called the magnetopause.
The ACE spacecraft monitors the solar wind from a position about 200 Earth radii (RE) sunward of the Earth. The real time solar wind data from this spacecraft allows us to predict what will happen at the Earth many minutes before the solar wind actually reaches us. Important solar wind values obtained from the ACE observations include the z-component of the interplanetary magnetic field (Bz) measured in units of nano-Tesla, and the dynamic pressure (also called the momentum flux) of the solar wind, measured in units of nano-Pascal.
Geosynchronous orbit (where many weather and communication satellites orbit) is depicted by the green dashed circle.
Here are all the gory details.
This movie is updated every five minutes
(unless there is an extended data gap in the ACE observations).
Click here to create movies for past intervals.
