The team working on ICON’s payload had a party over the weekend to commemorate their working together for the past year and their “empty nester” status now that the instrument has gone to Utah (Space Dynamics Lab) for testing and integration. UC Berkeley Electrical Engineer and party host Dorothy Gordon ordered the festive ICON cake from a local bakery. She said, “I had a great time working with the ICON-ICP (instrument control package) team and just wanted to get them all together again before we all drift off.” The send-off after their intensive work together takes place one year before ICON launches, so the cake could also be an “anti-birthday cake” celebrating ICON’s minus-one birthday!

FUV is continuing its series of successful tests and calibrations at CSL in Belgium. Once all of instrument’s accelerometers have been mounted, the Z-axis vibration test will be conducted. FUV is on schedule for delivery for integration in Utah, early in 2016. 

The preliminary alignment for the Far Ultraviolet Spectrograph (FUV) instrument using visible wavelength light has been completed at Lockheed Martin. The next phase of testing will see the instrument ship to Belgium to complete the alignment in the FUV in a specialized vacuum chamber.

The FUV ICON instrument has an articulating field of view. In order to accommodate this, special machinery is required to rotate the instrument during alignment, testing and calibration while inside the vacuum chamber. Centre Spatial de Liege (CSL) in Belgium will provide this unique ultraviolet vacuum facility.

The design for the FUV instrument is such that the optical system can be focused using visible light and a visible grating, as well as FUV light and grating. This is preferable, since alignment using UV must be performed in a vacuum chamber, which makes it more challenging to conduct the alignment.

Over the past four weeks, the SSL team has been traveling to Lockheed Martin where the instruments’ mirrors were carefully adjusted to achieve best focus and optimum spectral performance at visible wavelengths. The visible wavelengths chosen were suitably scaled to simulate performance at the FUV operating wavelength.

The next phase of testing will see the optics package ship to Centre Spatial de Liege (CSL) in Belgium. After verifying the visible alignments were maintained, and no shifts happened during transport, the UV grating and the two UV cameras will be installed and UV alignment will begin.

ICON's Extreme Ultraviolet (EUV) instrument is an “imaging spectrometer”. Its 2 dimensional detector records spectral information over the range 58.4 to 83.4 nm in the one direction, and records 12 degree wide x 1/4 degree high slices of the sky over a 16 degree field of view in the other direction.

In preparation for alignment of the toroidal grating used in the EUV instrument, an optical system has been setup to simulate the cylindrical wavefront. This simulates the instrument’s view for each slice of sky while in orbit. The optical set up consists of a convex sphere and a concave toroid that produces a line image on the EUV entrance slit to simulate what EUV will observe in space. This optics pair will be used to first align the EUV instrument using visible light, then the final alignment will take place in a vacuum chamber using EUV radiation, since EUV light is not transmitted in air.