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and leave C2's view of it middle or late on June 8. The actual transit won't take place as seen from SOHO, however.
• How does it happen that the SOHO spacecraft view is the same as ours on Earth? This spacecraft is in a halo orbit, moving around the sun-Earth Lagrangian point or L1 point, a point between the Earth and the sun where there is some relative stability, gravitationally, in contrast to other points in space. There are five Lagrangian points in the Earth-sun system, as shown in the image at right. They are the five positions in this system where a small object (like a

spacecraft) affected only by gravity can theoretically be stationary relative to the Earth and sun. SOHO actually orbits around the L1 point, so it is not exactly stationary at the point. Still, as Earth moves around the sun, the SOHO spacecraft does, too, with its perspective on the sun staying more or less the same as ours.
• Meanwhile, astronaut Don Pettit in the International Space Station is about to become the first human to witness and photograph a transit of Venus from space. His images and commentary will be streamed to Earth during the transit on June 5-6. Read about Pettit's plans to observe the Venus transit here.
• Also, for a space view of the transit, try the Solar Dynamics Observatory (SDO)'s Facebook page.
• Transits come in pairs, with over a century between transit pairs. So the last Venus transit wasn't so long ago: June 8, 2004. The image above shows what SOHO saw of that transit. Before the 2004 and 2012 Venus transits, the last ones were in the late 1800s. The next one won't be until 2117!
• Bottom line: On June 1, 2012, the SOHO's LASCO C3 camera of NASA's sun-observing SOHO spacecraft first caught sight of the planet Venus as it prepares to pass in front of the sun in a spectacular Venus transit - last one in our lifetimes. The transit will occur on June 5-6. On June 2, SOHO's camera has captured another image, showing Venus edging closer. Look here to learn ways to view the transit of Venus.
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