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Recent results on study of ultra high energy radiation from astrophysical compact objects using the CYGNUS* array at Los Alamos are presented. Observation of episodic emissions from Her X-1 in 1986 are described. Two bursts of radiation on UT July 24 1986 were detected showing a periodicity of 1.2357±0.0003sec with a statistical significance of ~ 2 ×10-5. The showers were found to have a muon content similar to that for hadronic showers and the energy of their progenitors were greater than 400 TeV. The characteristic muon poor feature of similar gamma ray initiated showers was not observed for the signal.

The GRANDE experiment is a “next-generation” detector capable of making significant contributions to the fields of neutrino and γ-ray astrophysics as well as performing important “conventional” high-energy physics investigations. The detector, which covers an area of 250 m x 250 m, will have excellent coverage for potential sources of v emission in the southern hemisphere and of VHE and UHE sources in the northern hemisphere. For VHE and UHE showers, the low threshold (10 TeV) and complete coverage for all three shower components (electromagnetic, muonic, and hadronic), are unique. Excellent angular resolution, ≤ 1° for v’s and ≤ 0.3° for γ -rays, large acceptance, good energy resolution, and wide energy sensitivity will permit detailed studies of the observed signals enabling a quantitative confrontation with theoretical predictions. The detector and its capabilities will be described.