<P> Crux is bordered by the constellations Centaurus (which surrounds it on three sides) on the east, north and west, and Musca to the south . Covering 68 square degrees and 0.165% of the night sky, it is the smallest of the 88 constellations . The three - letter abbreviation for the constellation, as adopted by the International Astronomical Union in 1922, is' Cru' . The official constellation boundaries, as set by Eugène Delporte in 1930, are defined by a polygon of four segments . In the equatorial coordinate system, the right ascension coordinates of these borders lie between 11 56.13 and 12 57.45, while the declination coordinates are between − 55.68 ° and − 64.70 ° . The whole constellation is visible to observers south of latitude 25 ° N . </P> <P> In tropical regions Crux can be seen in the sky from April to June . Crux is exactly opposite to Cassiopeia on the celestial sphere, and therefore it cannot appear in the sky with the latter at the same time . For locations south of 34 ° S, Crux is circumpolar and thus always visible in the night sky . </P> <P> Crux is sometimes confused with the nearby False Cross by stargazers . Crux is somewhat kite - shaped (a Latin cross), and it has a fifth star (ε Crucis). The False Cross is diamond - shaped (a Greek cross), somewhat dimmer on average, does not have a fifth star and lacks the two prominent nearby "Pointer Stars ." </P> <P> Crux is easily visible from the southern hemisphere at practically any time of year . It is also visible near the horizon from tropical latitudes of the northern hemisphere for a few hours every night during the northern winter and spring . For instance, it is visible from Cancun or any other place at latitude 25 ° N or less at around 10 pm at the end of April . There are 5 main stars . Due to precession, Crux will move closer to the South Pole in the next millennia, up to 67 degrees south declination for the middle of the constellation . But in AD 18000 or BC 8000 Crux will be / was less than 30 degrees south declination making it visible in Northern Europe . Even in AD 14000 it will be visible for most parts of Europe and the whole United States . </P>

What are the stars in the southern cross called