Abstract
The Mercury Laser Altimeter (MLA) is one of the payload science instruments on the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) mission, which launched on August 3, 2004. The altimeter will measure the round-trip time of flight of transmitted laser pulses reflected from the surface of the planet that, in combination with the spacecraft orbit position and pointing data, gives a high-precision measurement of surface topography referenced to Mercury’s center of mass. MLA will sample the planet’s surface to within a 1-m range error when the line-of-sight range to Mercury is less than 1,200 km under spacecraft nadir pointing or the slant range is less than 800 km. The altimeter measurements will be used to determine the planet’s forced physical librations by tracking the motion of large-scale topographic features as a function of time. MLA’s laser pulse energy monitor and the echo pulse energy estimate will provide an active measurement of the surface reflectivity at 1,064 nm. This paper describes the instrument design, prelaunch testing, calibration, and results of postlaunch testing.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
J.B. Abshire, X. Sun, R.S. Afzal, Appl. Optics 39, 2449–2460 (2000)
G. Chin et al., Space Sci. Rev. (2007). doi:10.1007/s11214-007-9153-y
J.J. Degnan, J. Geodyn. 34, 503–549 (2002)
J. Garvin et al., Phys. Chem. Earth 23, 1053–1068 (1998)
S.E. Hawkins, III et al., Space Sci. Rev. (2007, this issue). doi:10.1007/s11214-007-9266-3
D.J. Krebs, A.M. Novo-Gradac, S.X. Li, S.J. Lindauer, R.S. Afzal, A.W. Yu, Appl. Optics 44, 1715–1718 (2005)
N. Paschalidis et al., IEEE Trans. Nucl. Sci. 49, 1156–1163 (2002)
L. Ramos-Izquierdo et al., Appl. Optics 44, 1748–1760 (2005)
D.E. Smith et al., Science 279, 1686–1692 (1998)
D.E. Smith et al., Science 311, 53 (2006)
S.C. Solomon et al., Planet. Space Sci. 49, 1445–1465 (2001)
X. Sun, J.F. Cavanaugh, J.C. Smith, A.E. Bartels, Proceedings of the 22nd International Laser Radar Conference (ILRC 2004). Special Publication SP-561, European Space Agency, Noordwijk, The Netherlands, 2004, pp. 961–964
M.T. Zuber et al., J. Geophys. Res. 97, 7781–7797 (1992)
H.J. Zwally et al., J. Geodyn. 34, 405–446 (2002)
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Cavanaugh, J.F., Smith, J.C., Sun, X. et al. The Mercury Laser Altimeter Instrument for the MESSENGER Mission. Space Sci Rev 131, 451–479 (2007). https://doi.org/10.1007/s11214-007-9273-4
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11214-007-9273-4