Sky map showing Jupiter and Venus in conjunction tonight, just about three degrees apart. (NASA)

Link: More detailed NASA sky map

NASA describes the pairing as “a spectacular double beacon.” The planets are in such cozy proximity that you can conceal them with “a pair of outstretched fingertips” as you reach towards the heavens. The time to see them is during the several hours right after sunset. Look towards the western sky. Venus will shine about 8 times brighter than its near neighbor Jupiter.

The joining of these two planets is known as a planetary conjunction. explains what sets this particular conjunction apart:

Venus-Jupiter conjunctions are fairly special events, occurring roughly every 13 months. And this one should be the best conjunction for several years to come for viewers in the Northern Hemisphere, experts say, because the two planets will be visible for so long in the evening sky. At mid-northern latitudes on Thursday, the pair should blaze bright over the western horizon for about four hours after sunset.

NASA video: Overview of night sky highlights during the month of March.

Eric Berger at the Houston Chronicle notes such close conjunctions don’t happen often, or about once every 24 years:

It happened in March, 1998, when Venus passed within 2.2 degrees of Jupiter, and in 2036 the planets will appear to pass within 4 degrees of one another.

Even as the planets move past each other after tonight, they will remain fairly close together through the end of the month when the crescent moon will join them in triangular formation once again. March 24 through 27 will be good times to view this spectacle.

As for now, Venus and Jupiter aren’t the only planets visible.

EarthSky tells us Mars will be prominent opposite those two planets in the eastern sky:

...looking east – you can’t miss the ruddy planet Mars. This world won’t be so brilliant in our sky again until April 2014. Mars shines from dusk till dawn

The U.S. Naval Observatory astronomy blog recommends checking Mars out with a small telescope to see its features in detail not possible with the blind eye:

...if you look at Mars between 11:00 pm and midnight you should be able to glimpse his bright north polar ice cap and the dark surface feature known as Syrtis Major.