Near-Infrared Sky Surveys
Session 35 -- Digitizing the Sky Part I
Oral presentation, Tuesday, 31, 1994, 8:30-12:30

## [35.04] Near-Infrared Sky Surveys

S. Kleinmann, S. Schneider, M. Skrutskie, M. Weinberg (UMASS), S. Price (AFPL), K. Matthews, B. Soifer (CIT), J. Huchra (CFA), C. Beichman, T. Chester, C. Lonsdale (IPAC), J. Elias (NOAO), J. Liebert (UofA), P. Seitzer (UMICH)

We summarize plans and initial results from surveys carried out from ground-based telescopes in the range 1.0---2.5 $\mu$m, focussing particularly on those surveys that promise information on large-scale structures.

Two very large area surveys in the near-infrared are being initiated this year: the Two Micron All Sky Survey (2MASS) and the Deep Near Infrared Survey (DENIS). Their parameters are:

\begin{center} {Parameters of the 2MASS and DENIS Projects} \\[.5ex] \begin{tabular}{lrr} Parameter & 2MASS & DENIS \\ \hline Sky Coverage & All Sky & Southern Hemisphere \\ Wavebands & J, H, and K$_s$ & I, J, and K \\ Pixel Size at K band & 2.0$^{\prime\prime} \times 2.0^{\prime\prime}$ & 3.0$^{\prime\prime} \times 3.0^{\prime\prime}$ \\ Telescope Size & 1.3m & 1.0m \\ Integration Time Per Field & 8 sec & 9 sec \\ \end{tabular} \end{center}

Details on the surveys' specific objectives, mapping techniques, time scales for intiation and completion, plans for data processing and release will be described.

Initial scientific and engineering results from each of these projects will also be presented. Results obtained with the prototype camera built for the 2MASS project provide measurements of star counts to K$_s$ = 14 over a large sampling of galactic coordinates, a census of variables in limited regions of the galactic plane, and the first census of a near-infrared-selected sample of bright galaxies. A number of surveys covering more limited regions of the sky but at greater depth are also being executed and/or planned, and the comparison of parameters and results from these surveys with the shallower, wide-field surveys will be presented.