NASA Messenger Mission: Update


The Messenger mission came to an official end the previous year in 2015 with a planned impact with Mercury’s surface

The spacecraft began orbiting Mercury on March 17, 2011 and orbited a total of 4,105 times.The craft was successfully able to receive all the data it was sent to collect and more, wildly exceeding its expectations, recording information on magnetic anomalies, ice filled craters, and other previously undiscovered features of the planet. Lenox Laser was responsible for fabricating the High Power Ceramic Apertures used for spatial filtering aboard the NASA Messenger space craft. The filters were used to enhance the power of Messenger’s optics.

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Use of SiC in a High Power Spatial Filter for Stray Light Reduction


Thomson scattering measurement of the electron temperature and density profiles in high temperature plasmas is a well established experimental technique. The existence of high levels of laser-line radiation (“stray laser light”) in the detected scattered light signal can lead to difficulty in system calibration.

Spatial filtering is a standard technique for improving the spatial profile of low-power laser beams. Focusing a beam through a pinhole aperture allows removal of spatial irregularities caused by nonlinear effects of amplification, dust or imperfect optics.

Silicon carbide is often used as an aperture material due to its high damage threshold.
Lenox Laser, Inc. of Glen Arm, Maryland, has laser drilled 210 micron apertures in SiC disks for such applications as stated above.  Experiments have shown that SiC apertures perform better than copper apertures.  It was found that the steady state stray light level for SiC was significantly less than for Cu.  Thus a silicon carbide aperture performed better than copper for irradiance at the spatial filter focus.

High Energy Aperture Holder (MT-1, MT-1R)


Spatial filtering of a high energy laser beam is not a trivial problem when the energy density of the focused beam approaches the ablation threshold of the optical aperture material.
Materials with a high ablation threshold have very low thermal conductivity; thus, depending upon the repetition rate of laser pulses, can become subject to melting proceeded by aperture damage.
The Lenox Laser Corporation has developed the MT-1R high energy aperture holder that uses the combination of reflecting and heat dissipating parts to reduce by a few orders of magnitude the energy density that reaches the aperture. This method significantly extends the lifetime of the optical aperture. The MT-1R dimensions were selected in order to fit most of the optomechanical mounts designed for one inch mirrors or lenses provided by leading manufacturers, namely CVI-Melles Griot, Newport, New Focus, Thorlabs, Edmund Optics, etc.
When MT-1R is mounted in one of the above mentioned mounts it becomes an integrative part of the existing optical layout or device and does not require any additional adaptors.

Mercury Messenger Mission


NASA’s Mercury MESSENGER Mission was launched from Cape Canaveral on August 3, 2004. Lenox Laser, Inc. was commissioned by NASA to fabricate High Power Ceramic Apertures for spatial filtering which required laser drilling holes (a few microns in diameter) with great accuracy and precision. Ceramic is just one of many readily available materials Lenox Laser is able to process to custom specifications with a relatively short lead time.

MESSENGER (MErcury Surface, Space, ENvironmental, GEochemistry, and Ranging) is scheduled to “flyby” Mercury on October 6, 2008, and ultimately be inserted in the planet’s orbit by March 18, 2011. The Lenox Laser engineering and production teams take great pride in their “microscopic” contribution to the advancement of our knowledge of the solar system and of the universe.

NASA Messenger


NASA’s MESSENGER – set to become the first spacecraft to orbit the planet Mercury – launched today at 2:15:56 a.m. EDT aboard a Boeing Delta II rocket from Cape Canaveral Air Force Station, Fla.

NASA: Lenox Laser fabricated High Power Ceramic Apertures for spatial filtering aboard NASA’s Messenger Mission. We personally hand delivered these critical apertures to the engineers at NASA Goddard Space Flight Center.

Lenox Laser took the opportunity of the visit to show engineers some of the latest fiber laser technology that is being developed by IPG Photonics.

The Messenger is scheduled to leave July 30th, 2004 and should fly by Venus in October 2006 and then finally reach Mercury by January 2008.