We report the discovery of two ultra-faint stellar systems found in early data from the DECam Local Volume Exploration survey (DELVE). The first system, Centaurus I (DELVE J1238−4054), is identified as a resolved overdensity of old and metal-poor stars with a heliocentric distance of D = 116.3 +0.6 −0.6 kpc, a half-light radius of r h = 2.3 +0.4 −0.3 arcmin, an age of τ > 12.85 Gyr, a metallicity of Z = 0.0002 +0.0001 −0.0002 , and an absolute magnitude of M V = −5.55 +0.11 −0.11 mag. This characterization is consistent with the population of ultra-faint satellites, and confirmation of this system would make Centaurus I one of the brightest recently discovered ultra-faint dwarf galaxies. Centaurus I is detected in Gaia DR2 with a clear and distinct proper motion signal, confirming that it is a real association of stars distinct from the Milky Way foreground; this is further supported by the clustering of blue horizontal branch stars near the centroid of the system. The second system, DELVE 1 (DELVE J1630−0058), is identified as a resolved overdensity of stars with a heliocentric distance of D = 19.0 +0.5 −0.6 kpc, a half-light radius of r h = 0.97 +0.24 −0.17 arcmin, an age of τ = 12.5 +1.0 −0.7 Gyr, a metallicity of Z = 0.0005 +0.0002 −0.0001 , and an absolute magnitude of M V = −0.2 +0.8 −0.6 mag, consistent with the known population of faint halo star clusters. Given the low number of probable member stars at magnitudes accessible with Gaia DR2, a proper motion signal for DELVE 1 is only marginally detected. We compare the spatial position and proper motion of both Centaurus I and DELVE 1 with simulations of the accreted satellite population of the Large Magellanic Cloud (LMC) and find that neither is likely to be associated with the LMC.

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