RADAR-BRIGHT FEATURES ON NORTH POLAR MERCURY
(PDF abstract, 77 kb)

July 1999

GOLDSTONE/VLA OBSERVATION OF MARS
Courtesy B. J. Butler, M. A. Slade, R. F. Jurgens
(PDF abstract, 87 kb)

June 25, 1999

RADAR IMAGES OF THE PLANET MERCURY

August 1991 and February 1994

MERCURY CLOSURE POINTS FOR TESTING GRAVITATIONAL THEORIES

Group Supervisor: Dr. Martin Slade

Introduction

Rotation of Mars (209k GIF animation)

Rotation of Mercury (383k GIF animation)

The Planetary Radar Group is Group F in Section 332, the Communications Architectures and Research Section. We provide the advanced engineering and we direct the development of the technology needed to sustain and enhance the unique Goldstone Solar System Radar.

We are the interface between scientific research goals using the Radar and the engineering technology to accomplish these goals.

Group F Group members and their specialities
Goldstone Solar System Radar: A brief review

The Radar is part of the Deep Space Network (DSN) and is located at Goldstone in the Mojave Desert some 180 miles north-east of Los Angeles. It is sponsored by the Interplanetary Network Directorate (IND). It operates from the 70 meter antenna DSS-14 at the Mars site at Goldstone. We use the Radar for investigations in planetary astronomy. We support the research of radar astronomers in the Group and in the Space and Earth Sciences Program Directorate (SESPD) at JPL, as well as visiting scientists.

GSSR Observing Proposal <Word 6 format> <ASCII Text>
GSSR Observing Proposal Review Process
GSSR Bibliography 1980-1998
Results of the 1997 Arecibo to Goldstone Titan Observations
Goldstone Map of Goldstone site
DSS14 Picture of the 70 meter Antenna
Interplanetary Network Directorate (IND) which runs the DSN
Engineering and Science Directorate (ESD) Division 32 Planetary Science matters.

Radar Operation

The principles of Radar operation generally require that we transmit as much power as we can, and the receiver system is as sensitive as we can make it to register the usually faint echo power reflected from the target.

We have two powerful Transmitters on the 70 meter antenna, one developing 400 kW at S-Band (2320 MHz, wavelength 13 cm), and other 500 kW at X-Band (8560 MHz, wavelength 3.5 cm) Today we use X-Band almost exclusively. We have cryogenically cooled Low Noise Amplifiers as the first stage of the Receiver.

In order to confirm that the experiment is proceeding successsfully, we operate with a real-time Data Acquisition System which performs preliminary processing and displays the currently received echo power.

Principles of Radar A brief description of radar operation
The GSSR Receiving System, the journey from mere echo numbers to Radar science image.
Transmitters How we get high power and radiate into Space
Low Noise Amplifiers The very sensitive first stage of the receiving chain; scratching the echo from oblivion.
Receiver Making the echo a useful size
GSSR Data Acquisition System

Radar Science

The Radar can observe any accessible Solar System target. We can obtain echoes from Mercury, Venus, Mars, the satellites of Jupiter and Saturn, the Moon, and asteroids and comets. The remaining outer planets, Uranus, Neptune, and Pluto, are too distant to produce a detectable echo at Goldstone with the current equipment.

Near-Earth asteroids, in particular, such as Toutatis and Geographos are prime targets. These are increasingly prominent in scientific interest and concern. Specifically for these we have developed the Single Horn System. This allows fast switching of the radar high power radar for targets which pass close to the Earth.

We use the Radar to investigate the statistics of Orbital Debris. This is material in low-Earth orbit resulting from spacecraft activities and the break-up of satellites and rocket parts. Knowledge about this is crucially important for design of shielding for Space Station modules. The Radar is capable of sensing rice-grained sized particles, which form a large part of the debris.

Radar Results and Images
Single Horn System
Near Earth Asteroid Radar Observations
MARS Radar Observations
Orbital Debris Radar Investigations

Most observations take place exclusively at Goldstone, usually at DSS-14 alone, sometimes with DSS-13, the 34-m antenna, as a second receiving site. Other 34-m antennas will be used as they come on-line.
Occasionally we have joint observations with other observing sites; e.g. we also receive radar echoes at the NRAO Very Large Array in the New Mexico desert. We have an active scientific and engineering collaboration with the NAIC Arecibo in Puerto Rico, since this is the only other observatory which does planetary radar. The advantages of sharing common radar data formats and data reduction software with the Arecibo Observatory are obvious.

DSS-14: the 70 meter Antenna at Goldstone
DSS-14 X-band/K-band Research Cone
 
Quasi-Optical Switch Movie (429k GIF animation)
 

Quasi-Optical Switch Movie (8 MB MOV file)
DSS-14 Quasi-Optical Switch Assembly
DSS-14 Quasi-Optical Switch, Transmit Position
DSS-14 Quasi-Optical Switch, Receive Position
DSS-13: the 34 meter Antenna at Goldstone
 

Overall scientific direction of the Goldstone Radar comes from the Space and Earth Science Programs Directorate (SESPD), which in turn reports to NASA Solar System Exploration Division

Space and Earth Science Programs Directorate (SESPD)

Radar Use

In principle anyone with peer-reviewed planetary science funds may propose an experiment which needs the Radar. The applicant presents their proposal for general approval of all users of the DSS14 antenna and the DSN. Approval leads to an application for schedule time, in competition with the other users and their priorities. Generally proposals from outside JPL will have a JPL Radar scientist as a collaborator or at least as an advisor. to guide the process in-house to the actual antenna track time.
There is a User's Guide which advises nomenclature, describes the various Radar observing configurations, and details the other requirements necessary for an observation run or radar track.

GSSR User's Guide

Radar Engineering

The engineering direction of the Radar develops principally from the scientific requirements established by the Space and Earth Science Programs Directorate (SESPD). We formulate implementation efforts within JPL Division 33, working very closely with TMOD 940 Office DSN Data Systems which has overall responsibility for DSN Implementation Engineering.

Many of the features in the Radar are unique in the DSN and also in the world. The successful operation of the world's most powerful X-Band continuous wave (CW) transmitters in particular requires dedicated and extensive expertise. The GSSR still aims to develop and integrate new technologies such as the all-digital JPL Block V Receiver, to improve the science return and operational reliability.

It is our purpose to increase productivity of antenna use, to get more and better images per transmitted photon per transmitter second.

N A S A - The National Aeronautics and Space Administration

NASA Exploration Directorate Goals and Activities for Solar System Research
NASA Science Mission Directorate NASA's Space Science Program
NASA Home Page The NASA Homepage
The NASA Headquarters Home Page What is on in Washington
NASA in your life More NASA general information

N A S A - Near Earth Objects Report

The N E X T BIG ONE??!!
See Near-Earth Objects or go directly to
The Report of the Near-Earth Objects Survey Working Group from June 1995

Last Update: 03 April 2006

Send comments to: Martin Slade
Martin.A.Slade[at]jpl.nasa.gov