Europa Clipper’s SUrface Dust Analyzer (SUDA) sensor head is shown in a clean room at the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado Boulder.
Tiny meteorites eject bits of Europa’s surface into space and a subsurface ocean or in-ice water reservoirs might vent material into space as plumes. To study this, SUDA will scoop up larger particles from these plumes and identify their chemistry, revealing Europa’s surface composition including potential organic molecules. SUDA can detect salts in the dust and ice grains, providing additional information about a subsurface ocean. If a subsurface ocean or reservoir is venting material into space as plumes, SUDA will help us to determine if Europa’s water is suitable for some form of life.
When dust enters SUDA, it passes through a series of metal mesh grids. These grids are used for a variety of purposes, including sensing the charge and speed of incoming dust particles. Measuring the dust’s speed allows scientists to identify its area of origin on Europa’s surface. The dust then strikes a metal target plate visible at the back of the cavity. The energy of this impact is enough to break a fraction of the dust particle into individual molecules, which are electrically charged. This allows the ion detector to determine the mass and abundance of the molecules within the dust particle, including (if present) organic molecules such as amino acids.
Europa Clipper will conduct nearly 50 flybys of Europa, which scientists are confident has an internal ocean containing twice as much water as Earth’s oceans combined. And the moon may currently have conditions suitable for supporting life. The spacecraft’s nine science instruments will gather data on the moon’s atmosphere, surface, and interior – information that scientists will use to gauge the depth and salinity of the ocean, the thickness of the ice crust, and potential plumes that may be venting subsurface water into space.