Basic Features and Functions in the NASA Planck Archive (NPA)

This page is an overview of the basic features and functions of the NASA Planck Archive (NPA); for an even faster overview, see the Quick-Start Guide. Most of this file follows the blue tabs across the top of the Image Service.

Contents of page/chapter:
+Planck Mission
+Searches -- The basics of searching
+History -- Your search history
+Help -- Getting more help
+Catalogs -- Retrieving and using catalogs
+Background Monitor -- Downloading data and catalogs in the background

 

Planck Mission

The Planck Telescope observes the entire sky at frequencies ranging from 30 - 857 GHz. The releases of Planck data include: Users have full access to the Planck catalogs through this tool, and the archive enables sorting and selection of columns of data characteristics.

Searches -- The basics of searching

There are basically three ways to search the NPA. (1) TOI (time ordered information); this option provides for adding individual measurements of sky intensity together. (2) Browse catalogs; since Planck observations cover the entire sky, this option loads the entire catalog by frequency and you can browse through it interactively (e.g., all positions, but one wavelength). (3) Cutout visualization; search the multiple frequency data by position (e.g., all wavelengths, but one position). The default when loading the tool is the TOI search; other searches can be accessed from the left hand side of the search window. After a search, you can perform additional searches via clicking on the "Searches" blue tab at top left.

For TOI searches and Visualization searches, you enter a position anywhere in the sky. You may enter target names, which will be automatically resolved into coordinates using NED or Simbad. Alternatively, you may enter coordinates directly. These coordinates can be in decimal degrees or in hh:mm:ss dd:mm:ss format. By default, it assumes you are working in J2000 coordinates; you can also specify galactic, ecliptic, or B1950 coordinates as follows:

Examples are given below the text entry box before you start typing in the box. As you are completing a valid coordinate entry, it echoes back to you what it thinks you are entering. Look right below the box in which you are typing the coordinates to see it dynamically change.

For the browse catalog searches, the simplest initial option is to just ask it to load the catalog at any given frequency. It will then load the catalog for you, enabling you to browse it. You can impose filters from the search page or after the catalog has loaded; see filtering information.

A visualization search (multi-wavelength, positional search) will return the rows of the catalog selected by the input parameters, together with preview images. In the lower portion of the NPA window, images will appear in FITS format: data from Planck (JPEG images only in the ERCSC Release), WMAP, and IRAS will be shown. See the section on visualization for more information on the options within the visualization tabs.

Searching is described in detail in the section on searching, results are discussed in the section on results, and downloading data is discussed in the section on downloads.

You may wish to impose additional filters on your search results; see the section on filtering search results for more information.

History -- Your search history

The History menu option (blue tab at the top of the window, next to "Searches") gives you access to your own search history.

All of the single-position searches that you perform during a given session with the NPA are remembered in the search history panel. A high-level summary of the search is also listed -- what kind of search you performed and which parameters you used.

You can resubmit the search (see buttons at top left of the search history window), remove the search from your history, or save the search as a favorite search to which you can return at a later time/date. However, in order to return to it during a different session, you do need to be logged in when you save the search -- see the user registration section.

Help -- Getting more help

More information on Planck can be found at http://planck.caltech.edu/index.html or https://planck.ipac.caltech.edu/ .

You can submit questions to the IRSA Help Desk .

Have a question? Please read the frequently asked questions (FAQs) first.

The IRSA YouTube channel has several tutorials, though at this time, there are none solely on Planck. There are several that cover the basic operation of IRSA tools that have this look-and-feel.

Found a bug? The known bugs and issues in this version of the NASA Planck Archive (NPA) are listed here . If you think you have found a bug, please check this list before reporting it, and read the online NPA help. It may be a "feature" we already know about. If you have found a new, real bug then please do let us know by sending email to the Help Desk . Please include your operating system version and your browser software and version.

Catalogs -- Retrieving and using catalogs

(Note that this blue tab is only available after you have performed at least one search.)

You can choose from any of a wide variety of additional catalogs to load and overlay on your visualized data. They can be catalogs from IRSA or your own catalogs from disk. You can also make plots from the catalogs.

For more on catalogs, see the Catalogs section.

Background Monitor -- Downloading data and catalogs in the background

For information about downloading data (e.g., how to initiate it), please see the Downloads section.

The Background Monitor appears as a blue tab (or button) in the upper right of your window to keep track of the data downloads you have requested. It actively changes to reflect what it is doing ("Preparing", etc., e.g.,: ) All data packaging all goes to the Background Monitor; larger catalog requests are also sent to the Background Monitor.

A pop-up window can be called up at any time by clicking the "Background Monitor" tab. You can watch your data or catalog being retrieved. It will update that window when the data are available for download and overlay on your image, providing a link for obtaining the data. It also keeps track of the downloads you have requested during the same session, and indicates with a checkmark those that you have already loaded. Remove them from the list by clicking on the blue 'x'.

To stop any query mid-way through, click on the little red octagon ("stop sign") that appears next to the query in the Background Monitor pop-up.

If you forgot to put in your email at the beginning, or if the packaging is taking longer than you expected, you can click on "Add email" (or "change email") from the lower right of the Background Monitor popup and add (or change) your email during the packaging process.

The Background Monitor will also keep track of catalog downloads for you. The monitor will dynamically update to reflect its status, and will let you know when the catalog is ready to download or display. Open the background monitor and click on the catalog name to load it into a tab of its own. For more on catalogs, see the Catalog section.

Selecting Data to Download

There are basically two ways to download data -- clicking a diskette icon or selecting tickboxes and selecting "Prepare Download."

The diskette icon () can save only the current image (if selected from the image toolbox) or just the current catalog (if selected from the upper right of any catalog window).

If checkboxes appear in the upper left of images or on the far left hand side of a row in a catalog, you can select multiple items for packaging and download; additional data come with this packaged download. After deciding which data to download, click the checkboxes to select specific data files, and then click "Prepare Download" to begin the packaging and downloading process. A pop-up window will appear in order to define exactly what kinds of data you would like to have packaged up. Clicking "Prepare Download" in the pop-up initializes this packaging process.

After you click "Prepare Download", the packaging process moves to the Background Monitor. The background monitor can be called up by simply clicking on the blue tab. You can watch your data being packaged, and when the data are available for download, it will update that panel, providing a link for downloading the packaged data. Your most recent download request appears on the top of the list.

Note that you control where the data are saved on your disk through your browser; your browser may be configured to store all downloads in a particular location on your disk. Look for a "Downloads" folder or search for recently modified files.

For more specifics on how to download data, see the Downloads section.