MPj Astro - Version 1.52 MPj Astro is an easy to use planetarium type astronomy programme for Macintosh computers. It will display the positions of the stars, planets, comets, Sun and Moon for any location on earth from 2000 BC to the year 6000. Use MPj Astro to locate and identify objects in the sky, learn the constellations, track comets, plot eclipses and print star maps.