Table 1.

Content of rare earth elements (REEs; reported as μg/g; mean ± standard deviation) in the basalt substrate used in this experiment and concentrations (total nanograms leached into the chamber fluid volume of 6 mL) at the end of the BioRock experiment in S. desiccabilis bioleaching chambers and non-biological controls on-board the International Space Station.

		S. desiccabilis			non-biological control
REE	Concentration in basalt (μg/g)	Microgravity	Mars gravity	Earth gravity	Microgravity	Mars gravity	Earth gravity
La	6.81	3.60 ± 1.26	4.96 ± 0.51	3.74 ± 0.51	3.22 ± 2.20	2.56 ± 0.89	1.66 ± 0.23
Ce	13.53	8.85 ± 2.89	9.26 ± 1.94	7.18 ± 0.99	6.45 ± 3.99	5.79 ± 2.06	4.39 ± 1.26
Pr	2.32	1.12 ± 0.43	1.67 ± 0.48	1.07 ± 0.11	0.96 ± 0.64	0.85 ± 0.28	0.48 ± 0.04
Nd	11.57	5.35 ± 2.02	7.89 ± 1.99	5.20 ± 0.47	4.68 ± 3.49	4.28 ± 1.46	2.28 ± 0.24
Sm	3.04	1.44 ± 0.57	2.03 ± 0.36	1.42 ± 0.12	1.13 ± 0.90	1.06 ± 0.37	0.54 ± 0.07
Eu	1.13	0.51 ± 0.16	0.66 ± 0.07	0.53 ± 0.04	0.44 ± 0.25	0.42 ± 0.11	0.27 ± 0.03
Gd	3.67	2.03 ± 0.86	2.93 ± 0.51	2.18 ± 0.13	1.60 ± 1.37	1.36 ± 0.52	0.70 ± 0.10
Tb	0.57	0.42 ± 0.14	0.57 ± 0.08	0.44 ± 0.01	0.30 ± 0.21	0.26 ± 0.07	0.16 ± 0.02
Dy	3.92	2.82 ± 1.00	3.99 ± 0.55	3.08 ± 0.21	1.86 ± 1.43	1.58 ± 0.52	0.92 ± 0.11
Ho	0.80	0.69 ± 0.27	0.98 ± 0.08	0.78 ± 0.08	0.45 ± 0.37	0.36 ± 0.13	0.20 ± 0.03
Er	2.44	2.34 ± 1.01	3.37 ± 0.22	2.75 ± 0.32	1.49 ± 1.26	1.17 ± 0.47	0.64 ± 0.11
Tm	0.29	0.42 ± 0.16	0.58 ± 0.04	0.49 ± 0.06	0.29 ± 0.19	0.24 ± 0.07	0.16 ± 0.01
Yb	2.11	2.44 ± 1.09	3.52 ± 0.36	2.83 ± 0.35	1.47 ± 1.19	1.16 ± 0.44	0.67 ± 0.11
Lu	0.31	0.49 ± 0.20	0.68 ± 0.08	0.57 ± 0.07	0.33 ± 0.22	0.27 ± 0.08	0.18 ± 0.02

(n = 3 biologically independent samples with the exception of one non-biological microgravity and non-biological ground control sample which are not included. Full data set in Supplementary Table 2).