Abstract: A method and system are provided for performing magnetic anomaly sensing. Each of two magnetometers generates magnetic field measurements. The magnetometers define a one-dimensional gradiometer having a baseline between them. A difference value is generated using the magnetic field measurements. The magnetometers are independently moved to maintain the baseline when the difference value is unchanging. Detection of a magnetic anomaly by a first magnetometer is indicated when the difference value deviates. The second magnetometer is then maneuvered until the magnetic field measurements generated thereby are indicative of detection of the magnetic anomaly by the second magnetometer. When this occurs, an adjusted baseline is defined between the magnetometers. At least one of the magnetometers is maneuvered to position the adjusted baseline in each of three orthogonal dimensions.