Image Archives

The image archive access panel requires the following common information for all images:

  • The object name/location can be any string that can be resolved into a location on the sky. The string is first sent to NED, then SIMBAD to see if it corresponds to an object name understood by those services. If so, the retrieved coordinates are used with the image retieval service.

    If not, the string is parsed to see if it can be interpreted directly as a coordinate and this is used. Otherwise, an error message is created.

  • The file into which the data is to be saved can be entered directly or can be selected through a standard file/directory selection pop-up.

In addition, each specific dataset requires custom parameters, which are covered in the following help sections:

Retrieved files are automatically displayed by default.

 

Retrieving ISSA Images

The IRAS Sky Survey Atlas (ISSA) is a set of images which together cover the entire sky at infrared wavelengths (12, 25, 60, and 100 micron wavelengths). The archive service allows the user to select which of these four to retrieve and to specify the size on the sky desired (up to the ISSA plate size of 12.5 degrees square). This is done through a pair of selection pulldowns on the ISSA subpanel of the Image Archive data retrieval panel.

 

Retrieving 2MASS Images

The Two-Micron All-Sky Survey Atlas (2MASS) is a set of images which together cover the entire sky at infrared wavelengths (J, H, and K filters). The archive service allows the user to select which of these three to retrieve and to specify the size on the sky desired (up to the 2MASS plate size of 6x12 arcmin). This is done through a pair of selection pulldowns on the 2MASS subpanel of the Image Archive data retrieval panel.

Currently, Oasis serves only 2MASS Quick-look images, which do not provide valid fluxes.

 

Retrieving DSS Images

The Digitized Sky Survey (DSS) is a set of images which together cover the entire sky at visible wavelengths. The archive service allows the user to specify the size of the image retrieved (text fields for height and width in arcminutes) and choose which version of the data to download (a pulldown with a choice of generation). The First Generation comprises the older surveys, scanned at about 1.7 arcsec per pixel. The Second Generation is from a newer ongoing survey, scanned at about 1 arcsec per pixel. The request setup is done through the DSS subpanel of the Image Archive data retrieval panel.

 

Retrieving MSX Images

The Mid-course Space Experiment (MSX) generated a set of images of the Galactic Plane for |b| < 5 degrees in four mid-infrared spectral bands (~8-20 microns). The archive service allows the user to select which of these four to retrieve and to specify the size on the sky desired (up to a maximum of 1.5 degrees square). This is done through a pair of selection pulldowns on the MSX subpanel of the Image Archive data retrieval panel.

 

Retrieving IGA Images

The IRAS Galaxy Atlas (IGA) is a set of superresolution images of the Galactic Plane (|b| < 4.7 degrees) made from the IRAS 60 and 100 micron data. The archive service allows the user to select which of wavelength to retrieve and which interation of the superresolution processing to use. A beam map generated as part of this processing can optionally be requested instead. This is done through a pair of selection pulldowns and a checkbox on the IGA subpanel of the Image Archive data retrieval panel.

 

Retrieving VLA FIRST Images

FIRST (Faint Images of the Radio Sky at Twenty-cm) produced the radio equivalent of the Palomar Observatory Sky Survey over 10,000 square degrees of the North and South Galactic Caps. The archive service allows the user to specify the size on the sky desired in arcmin. This is done through a pair of selection pulldowns on the FIRST subpanel of the Image Archive data retrieval panel.

 

Retrieving NVSS Images

The NRAO/VLA Sky Survey (NVSS) was done with the National Radio Astronomy Observatory's Very Large Array telescope at a wavelength of 20 cm (1.4 GHz) and produced images of the sky north of declination -40 deg with a resolution of 45 arcsec. The archive service allows the user to specify whether they want total intensity or linear polarization images, the size on the sky (in arcmin), pixel spacing (in arcsec), and the output image rotation. This is done through text areas and a pulldown on the NVSS subpanel of the Image Archive data retrieval panel.