Gravitational Waves, Tumbleweeds and Western Kingbirds

June 23, 2017


Photographer: Rebecca Roush
Summary Author: Rebecca Roush

Gravitational waves are currently being researched intensely at the Laser Interferometer Gravitational-Wave Observatory (LIGO) in Hanford, Washington. Construction of the observatory and landscaping around it has resulted in two interesting and related phenomena: first, tumbleweeds can affect the measurements of gravitational waves and second, baling tumbleweeds provides Western Kingbirds with materials to build their nests in the observatory’s landscaping.

Baling machines are used to collect tumbleweeds that gather around the site’s buildings, including the observatory’s 2.5 mile-long arms. If not baled, tumbleweeds have the potential to affect the very sensitive instruments measuring gravitational waves. The bundles are secured with string, which opportunistic Western Kingbirds use to build their nests.

The photo on the left shows the baling equipment and some tumbleweeds beginning to accumulate near one of the observatory's extended arms. Once baled, they're distributed around the surrounding arid landscape to decompose. The photo on the right shows several kingbird nests in a planted deciduous tree on the observatory grounds. Note the red baling twine that the opportune birds have incorporated into their nests, making them look almost like decorations. Photo taken on April 19, 2017.