Introduction

This User’s Guide provides a brief overview of the Lunar Reconnaissance Orbiter Mission (LRO or “lro:”) namespace for those working with data from Lunar Reconnaissance Orbiter primary or extended missions.

Note that the Lunar Reconnaissance Orbiter legacy data migration is still active, with labels still being designed for some remaining instruments. This namespace is in active development and will continue to be so for the near future.

Data from the LRO mission was originally archived in PDS3 format and migration to PDS4 is underway.

This guide presents the major features of the namespace.

Overview of the Lunar Reconnaissance Orbiter (LRO) Mission Dictionary

The Lunar Reconnaissance Orbiter (LRO) Mission was launched June 18,2009. The LRO mission data were originally developed and archived in PDS3 format. This dictionary was developed as part of the PDS4 migration effort and includes all phases of the primary and extended mission.

Corrections, changes, and additions should be submitted through the PDS LDD Issue Repo.

Organization of Classes and Attributes

The Lunar Reconnaissance Orbiter dictionary has a single top-level class that must be used to access any of the LRO metadata classes. Below that, there are major subclasses for metadata that is common to all (or multiple instruments), as well as classes specific to particular instruments. Processed and calibrated data will generally have additional classes to provide instrument-specific processing details.

The following sections describe the major divisions of the Lunar Reconnaissance Orbiter Mission namespace, in the order in which they occur in the schema (and thus, labels).

Top-Level Class: <lro:LRO_Parameters>

The <lro:LRO_Parameters> class acts as a wrapper for all other LRO classes. At this level all attributes and (as of this writing) instrument classes are optional.

Although optional all labels should contains the attribute, <lro:mission_phase_name>, with the string identifying the mission phase. Mission phase names are unique to the primary or extended mission in which they occur. Available values are from LAUNCH through extended phases.

The major subclasses of the <lro:LRO_Parameters> class are for the various instruments on LRO:

You can see a top-level outline of the namespace under the Lunar Reconnaissance Orbiter (LRO) Mission Top-level Namespace Outline topic.

Subclass: <lro:Diviner_Parameters>

The <lro:Diviner_Parameters> class provides details specific to the Diviner experiment.

The Diviner Lunar Radar Experiment is a multi-channel solar reflectance and infrared radiometer that maps the temperature of the lunar surface at 500-meter horizontal scales. Diviner data sets are produced by the Diviner Science Team at the University of California, Los Angeles.

Subclass: <lro:LOLA_Parameters>

The <lro:LOLA_Parameters> class provides details specific to the Lunar Orbiter Laser Altimeter (LOLA).

LOLA is a pulse detection, time-of-flight laser altimeter. LOLA transmits a 5-spot pattern that measures the precise distance to the lunar surface at multiple points simultaneously, thus providing 5 profiles across the lunar surface. Each spot within the five-spot pattern has a diameter of approximately five meters; the spots are approximately 25 meters apart in the nominal 50-km-high mapping orbit in the form of a cross canted by 26 degrees counterclockwise, repeating approximately every 57 meters along-track. These spots provide up to five adjacent profiles whose separation depends on spacecraft altitude. The data set consists of uncalibrated observations, also known as EDRs. It is a time series collection of science and housekeeping data from LOLA, aggregated exactly as they are stored on the LRO spacecraft before being downlinked. Except where noted, they are complete and free from duplicates or errors.

Subclass: <lro:LROC_Parameters>

The <lro:LROC_Parameters> class provides details specific to the Lunar Reconnaissance Orbiter Camera suite.

The LRO Camera consists of two Narrow Angle Cameras (NACs) that provide 0.5 meter-scale panchromatic images over a combined 5 km swath, a Wide Angle Camera (WAC) to provide images at a scale of 100 meters/pixel in seven color bands over a 60 km swath, (during the nominal 50 km primary mission phase) and a Sequence and Compressor System (SCS) supporting data acquisition for both cameras. LROC is a modified version of the Mars Reconnaissance Orbiters ConTeXt Camera (CTX) and MARs Color Imager (MARCI), built by Malin Space Science Systems (MSSS) in San Diego, CA. The two NAC, WAC and SCS are located on the LRO Instrument bench, with NAC/WAC respective boresights aligned with the nadir (+Z) axis of the spacecraft.

Subclass: <lro:MiniRF_Parameters>

The <lro:MiniRF_Parameters> class provides details specific to the Mini-RF experiment.

Mini-RF is the Miniature Radio Frequency technology demonstration of a miniaturized multi-mode dual frequency dual polarization radar observatory. Mini-RF data sets are produced by the Mini-RF Science Team at the Johns Hopkins University Applied Physics Laboratory, Laurel, MD