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Where is Mercury now?


Mercury's orbit is so close to the Sun that we can only see it from Earth either just before sunrise or just after sunset. Below is a diagram of the orbits of the inner planets, as they appear today. In this view, the planets are all traveling counterclockwise about the Sun, and the Earth is rotating counterclockwise about its axis as well.

Do you think you should look for Mercury around sunrise or sunset? To see views of the sky at sunrise and sunset today, select the city nearest you in the menu box below, and click the "submit" button. In each diagram, the horizon is at the bottom and the directions are labelled just below. The positions of the inner planets are shown, and the yellow line is the path of the Sun just after sunrise or just before sunset. The time and date are stamped at the upper left corner of each picture.

If you want to see Mercury well with the naked eye, it's best to choose a time of year when the planet is above the horizon while the sky is fully dark - at least 40 minutes or so before sunrise, or after sunset. This means that Mercury is most visible at those times of year when it is at least 10 degrees above the horizon at sunrise or sunset. The diagrams can show you whether this is true today - notice that a scale of degrees of elevation is along the left side of each picture. Look in the direction where the Sun will rise in the morning, or where it has set in the evening, and you may be rewarded with a view of the innermost planet.

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This page uses the Java applet "Sky View Cafe" with permission of its developer, Kerry Shetline. To explore the full power of the applet, we encourage you to visit the Sky View Cafe website

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