Local Volume Mapper

The Local Volume Mapper (LVM) is an optical, integral-field spectroscopic survey that will target the Milky Way, Small and Large Magellanic Clouds, and other Local Volume galaxies. LVM will make use of new small telescopes and newly built spectrographs that cover a wavelength range of 3600-10000 Å, with spectral resolution R~4000 (based on the DESI spectrograph design). It will collect roughly 20 million contiguous spectra over 2,500 square degrees of sky.


Broad-band (optical) and narrow-band ([O III], H$\alpha$, [S II]) imaging of the LMC (<a href="https://ui.adsabs.harvard.edu/abs/2000ASPC..221...83S/abstract">Smith et al. 2000</a>).  The left-hand column demonstrates sampling at a spatial resolution of 100 pc, typically achieved by the best IFU data available today for external galaxies.  The resolution increases to the right, ending with the ~1 pc resolution that LVM will achieve in the Milky Way.  Note the qualitative change in appearance around 25 pc, when networks of shocks and ionization fronts become visible and then resolved at less than 10 pc.
Broad-band (optical) and narrow-band ([O III], H$\alpha$, [S II]) imaging of the LMC (Smith et al. 2000). The left-hand column demonstrates sampling at a spatial resolution of 100 pc, typically achieved by the best IFU data available today for external galaxies. The resolution increases to the right, ending with the ~1 pc resolution that LVM will achieve in the Milky Way. Note the qualitative change in appearance around 25 pc, when networks of shocks and ionization fronts become visible and then resolved at less than 10 pc.

Science Goals

Galaxy formation can be understood as a self-regulating process, with energy exchange between stars and interstellar gas occurring at numerous points in space and time. LVM will map the interstellar gas emission of the Milky Way and Local Group galaxies with unprecedented spatial resolution: reaching sub-parsec resolution in the Milky Way, 10s of parsecs resolution in the Magellanic Clouds, and down to <100 parsec resolution out to distances of several Mpc. LVM is thus well-positioned to study star formation and the physics of the interstellar medium in great detail by distinguishing individual star formation knots and the filamentary structures and shock networks between them. LVM will be able to connect studies across the parsec (molecular cloud) and kiloparsec (galaxy-wide) scales; this connection is fundamental to understand the physics governing star formation, the structure of the interstellar medium, the baryon cycle, and ultimately, the evolution of galaxies.

More details on the Local Volume Mapper and an extended description of its science goals can be found on the Science of SDSS-V page and in the SDSS-V White Paper SDSS-V: Pioneering Panoptic Spectroscopy.

Contact information

For more information, contact the SDSS-V Program Head for the Local Volume Mapper, Niv Drory (University of Texas at Austin).