 The "Collaborative Asteroid Lightcurve Link" assumes a standard albedo for stony asteroids of 0.20 and derives a diameter of 9.75 kilometers based on an absolute magnitude of 12.46.With a diameter of approximately 10 kilometers, "Amundsenia" is one of the largest mid-sized Mars-crossing asteroids such as 1139 Atami (9.35 km), 1474 Beira (14.9 km), 1011 Laodamia (7.39 km), 1727 Mette (est 9 km), 1131 Porzia (7.13 km), 1235 Schorria (est.9 km), 985 Rosina (8.18 km) 1310 Villigera (15.24 km), and 1468 Zomba (7 km); but still smaller than the largest members of this group, namely, 132 Aethra, 323 Brucia, 1508 Kemi, 2204 Lyyli and 512 Taurinensis, which are larger than 20 kilometers in diameter (in one or other given source).