1994A&A...291L..47L

As part of a survey for duplicity among nearby M dwarfs with the technique of near-infrared speckle imaging we detected two faint companions to the low-mass star LHS 1070. Apportioning the system brightness among the main component and the companions of this triple system, we obtain absolute brightnesses at 2.2µm of K_A=9.27mag, K_B=10.47mag and K_C=10.82mag. Based on the empirical mass-K magnitude relationship for M dwarfs (Henry & McCarthy 1993), a primary mass of m_A=0.099M_☉ is estimated, while the masses of the companions should be close to or even slightly below the hydrogen burning limit of 0.08 solar masses. LHS 1070 has an important advantage over the few still fainter candidates for substellar masses: orbital motion within this triple system with its small component separations of a few astronomical units will allow useful dynamical mass determinations for the companions within the next few years. The observed changes in relative position of the components between July 1993 and April 1994 appear compatible with the photometrically deduced very low component masses.