Upper limit concentrations of trapped xenon in individual interplanetary dust particles from the stratosphere

Upper limit for CH4 production from comet Kohoutek by high resolution tilting-filter photometry at 3.3 microns

Upper Limit for Interstellar Millicycle Gravitational Radiation

Upper limit of the angular velocity of neutron stars

Upper limit on solar interior rotation

Upper limit on Titan's atmospheric argon abundance

Upper Limit on X-rays from a New Supernova

Upper limits for stratospheric H2O2 and HOCl from high resolution balloon-borne infrared solar absorption spectra

Upper limits on hydrogen halides in Jupiter from Cassini/CIRS observations

Upper limits to (O) in the lower thermosphere from airglow

Upper limits to soft gamma-ray flux from seven X-ray sources and from the galactic plane

Upper limits to the interstellar radiation field between 775 and 1050 A

Upper limits to the S2 abundance in several comets observed with the International Ultraviolet Explorer

Upper mantle discontinuity structure beneath East Anatolian Plateau (Turkey) from receiver functions

Upper mantle flow beneath and around the Hangay dome, Central Mongolia

Upper mantle imaging beneath the Japan Islands by Hi-net tiltmeter recordings

Upper mantle isotopic components beneath the Ryukyu arc system: Evidence for ‘back-arc’ entrapment of Pacific MORB mantle

Upper mantle oxidation state: Ferric iron contents of Iherzolite spinels by 57 Fe Mössbauer spectroscopy and resultant oxygen fugacities

Upper mantle SH- and P-velocity structures and compositional models beneath southern Africa

Upper mantle tectonics: three-dimensional deformation, olivine crystallographic fabrics and seismic properties