Comet Hale Bopp Over Val Parola Pass

Comet Hale-Bopp , the Great Comet of 1997, became much brighter than any surrounding stars. It was seen even over bright city lights . Away from city lights, however, it put on quite a spectacular show . Here Comet Hale-Bopp was photographed above Val Parola Pass in the Dolomite mountains surrounding Cortina d'Ampezzo , Italy . Comet Hale-Bopp 's blue ion tail , consisting of ions from the comet's nucleus , is pushed out by the solar wind . The white dust tail is composed of larger particles of dust from the nucleus driven by the pressure of sunlight, that orbit behind the comet . Comet Hale-Bopp (C/1995 O1) remained visible to the unaided eye for 18 months -- longer than any other comet in recorded history. This year marks the 20th anniversary of Comet Hale-Bopp's last trip to the inner Solar System. The large comet is next expected to return around the year 4385 .