Detectability of hypothetical nearby Earth-like planets around M dwarfs with a single transit. Coloured dots show planets with an S/N of at least 5 for the corresponding spectral features (H₂O: blue, CH₄: green and CO₂: red). Morethan one colour means that multiple spectral features can be detected with a single transit. The sizes of the grey dots indicate the highest S/N of all spectral features. The numbers inside the coloured dots correspondto the following host stars: 1: Proxima Centauri, 2: Barnard’s star, 3: Wolf 359, 4: Ross 154, 5: Ross 248, 6: Ross 128, 7: GJ 15 B, 8: DX Cancri, 9: GJ 1061, 10: YZ Ceti, 11: Teegarden’s star, 12: Wolf 424, 13: L 1159-16, 14: GJ 1245 B, 15: GJ 1245 A, 16: GJ 412 B, 17: LHS 2090, 18: GJ 1116, 19: LHS 1723, 20: GJ 1005, 21: L 43-72, 22: GJ 3737, 23: GL Virginis, 24: GJ 1128, 25: LSPM J2146+3813, 26: Ross 619, 27: G 161-7, 28: GJ 4053, 29: G 141-36, 30: SCR J0740-4257, 31: GJ 1286, 32: LHS 1070, 33: SCR J0838-5855, 34: NLTT 40406, 35: GJ 3146, 36: LSPM J0539+4038.