NASA has said its flying observatory Sofia is preparing for its 2018 campaign, which will include, among others, observations of celestial magnetic fields, star-forming regions, comets and Saturn's giant moon Titan.This will be the fourth year of full operations for Sofia, short for Stratospheric Observatory for Infrared Astronomy, with observations planned between February 2018 and January 2019, NASA said on Friday.Sofia is a Boeing 747SP jetliner modified to carry a 100-inch diameter telescope. It is a joint project of NASA and the German Aerospace Centre, DLR. Scientists believe that the observatory's investigations will help them understand how magnetic fields affect the rate at which interstellar clouds condense to form new stars.One programme using the observatory's newest instrument, the High-resolution Airborne Wideband Camera-Plus, called HAWC+, will help astronomers better understand how energetic, active black holes contribute to the most luminous, distant galaxies, NASA said.These observations could help them learn whether the luminosity of these active black holes is driven by star formation or accretion of material onto the central black hole.Sofia will also conduct observations to better understand how methane levels change with seasons on Mars.Another team of researchers is planning to study comet 46P/Writanen as it passes close to the Earth, to search for clues in the comet's dust that may help better understand the evolution of the early solar system, the US space agency said.Researchers also plan to utilise Sofia's mobility to study the atmosphere of Saturn's moon Titan by studying its shadow as it passes in front of a star during an eclipse-like event called an occultation.