THREE months ago we saw a rare and interesting astronomical event take place. For only the second time since 1882 the planet Venus passed directly between the earth and the sun and we saw something known as a transit of Venus.
Unfortunately we will have to now wait another 105 years before we see it happen again.
That isn't the only transit to occur this year as technically the solar eclipse in December is a transit of the moon across the face of the sun.
But if we ignore the moon, looking from here on the earth we find that Mercury and Venus are the only planets that ever pass directly between us and the sun and consequently the only ones we ever get to see pass over the sun's disc.
Fortunately for us the sun appears quite big so the alignment doesn't have to be perfect and transits of either planet aren't all that rare.
But transits can be seen from other planets too. Besides Mercury, the closest planet to the sun, every planet will at some stage have another one pass directly between it and the sun. Of course the further out the planet is, the smaller the sun will appear and the more perfect the alignment has to be.
This means the further out in the solar system you live the less likely they are to happen.
Interestingly though, we have already had a transit visible from another planet occur this year. Back in February, if you were standing on the surface of Jupiter you would have seen a transit of Mercury.
And since this seems to be the year of Venus transits, amazingly there are two more coming up.
Assuming you had extended your holiday on Jupiter then next Thursday you would now see Venus cross the face of the sun. Moving out to Saturn, in late December you could then repeat the performance and once again see Venus transit the solar disc.
The rarest transit is that of Uranus as seen from Neptune. Between the years 0 and 4000 it does not happen. Not even once.
Humans unfortunately are not likely to be standing on the surface of either Jupiter or Saturn in the foreseeable future. They may however be on Mars in only a matter of decades.
So what about the next transits as seen from Mars? In the year 2030 Venus will cross the sun's disc and in 2084 Earth will be seen directly in front of the sun.
Will any earthling be there to see this event? I hope so, as that would be a sight not to be missed.