Imagine detecting echoes from the early universe right here. That was the mission of the MRAO Cosmic Anisotropy Telescope or CAT. This telescope once stood as a pioneering instrument. It was designed to measure fluctuations in the cosmic microwave background or CMB.
The MRAO Cosmic Anisotropy Telescope was built in the 1990s. It was an interferometer at the Mullard Radio Astronomy Observatory. This observatory is near Cambridge in England. The CAT was relatively small for radio interferometers. Its baselines ranged from 1 to 5 meters. This size was perfect for its specific task.
Its purpose? To study the faint variations in the CMB. These variations are called anisotropies. The Cosmic Anisotropy Telescope began operating in 1995. Its work continued until the year 2000. By then, the Very Small Array or VSA had made it obsolete.
In 1996, the MRAO Cosmic Anisotropy Telescope achieved a milestone. It published its first results. These were the highest resolution CMB detections at the time. The CAT’s findings revealed a crucial detail. The rise in fluctuation power towards scales of about 1 degree was matched by a decline in power at smaller angles. This confirmed the existence of the long-predicted acoustic peak in the CMB power spectrum. Further results were published in 1999.
The MRAO Cosmic Anisotropy Telescope played a vital role in cosmology. It helped confirm key predictions about the universe’s early development. Although the telescope was turned off and partly dismantled in 2000, its legacy lives on. The MRAO Cosmic Anisotropy Telescope’s successor is the Very Small Array. This array is a 14-element interferometer. It is now based in Tenerife.
The Mullard Radio Astronomy Observatory continues to be a hub of astronomical research. Here, scientists explore the universe using advanced instruments. The MRAO Cosmic Anisotropy Telescope may no longer be active, but its contributions have shaped our understanding of the cosmos. It proved invaluable in measuring tiny fluctuations in the CMB.