D/H ratios and ¹⁴N/¹⁵N ratios in solar system objects, compared to the protosolar (gray bands) and Earth (blue bands) values (Robert et al. 2000; Marty et al. 2011). Jupiter and Saturn values are from Marty et al. (2011), Füri & Marty (2015), and Fletcher et al. (2014); Titan values from Abbas et al. (2010), Niemann et al. (2010), and Mandt et al. (2009, 2014); meteorites from Waite et al. (2009) and Kerridge (1985); and comet values from Bockelée-Morvan et al. (1998), Meier et al. (1998), Crovisier et al. (2004a), Hartogh et al. (2011), Bockelée-Morvan et al. (2012), Bockelée-Morvan et al. (2008), Hutsemékers et al. (2009), Meech et al. (2011), and this paper. The symbols corresponding to each source are given in the enclosed legend box. They are ordered according to the species in which the ¹⁴N/¹⁵N was measured from left to right: atomic nitrogen, N₂ (as for Earth), ammonia, HCN, and CN. Empty symbols with names in italics are for lower limits on the ¹⁴N/¹⁵N .