4 ± 1.5 °C abrupt warming 11,270 yr ago identified from trapped air in Greenland ice

4-8 day planetary waves in the middle and upper atmosphere: What can theory and modeling tell us about the observations we make.

4.6 micron absorption features due to solid phase CO and cyano group molecules toward compact infrared sources

4.6 micron absorption features due to solid phase CO toward compact infrared sources

40 Ar / 39 Ar analysis of supergene jarosite and alunite: Implications to the paleoweathering history of the western USA and West Africa

40 Ar / 39 Ar and K---Ar dating of altered glassy volcanic rocks: the Dabi Volcanics, P.N.G.

40 Ar / 39 Ar results for alkali feldspars containing diffusion domains with differing activation energy

40 Ar- 39 Ar ages and trace element contents of Apollo 14 breccias; an interlaboratory cross-calibration of 40 Ar- 39 Ar standards

40 KG Sample of Fish-Clay from Stevns Klint, Denmark

400 Novae in M87

400 year record of Δ14C in tree rings: the solar-activity cycle before, during and after Maunder Minimum and the longer cycles.

408MHz galactic radio sources (Shaver+ 1970)

408MHz obs. of GPS sources from JVAS survey (Marecki+ 1999)

4098 galaxy clusters in SDSS Stripe 82 (Geach+, 2011)

40Ar-39Ar age determinations of lunar basalt meteorites Asuka 881757, Yamato 793169, Miller Range 05035, LaPaz Icefield 02205, Northwest Africa 479, and basaltic breccia Elephant Moraine 96008

40Ar-39Ar ages of H-chondrite impact melt breccias

40Ar-39Ar Dating of Pseudotachylites from the Witwatersrand Basin, South Africa, with Implications for the Formation of the Vredefort Dome

40Ar-39Ar dating of pseudotachylytes: the effect of clast-hosted extraneous argon in Cenozoic fault-generated friction melts from the West Antarctic Rift System

40Ar-39Ar geochronology of Tertiary mafic intrusions along the East Greenland rifted margin: Relation to flood basalts and the Iceland hotspot track

40Ar-39Ar Geochronology on Apollo 12 Regolith