NASA’s Lunar Reconnaissance Orbiter Images Saturn From 56 Miles Above the Moon

From a viewpoint about 90 kilometers (56 miles) above Lacus Veris, “Lake of Spring,” the camera aboard NASAEstablished in 1958, the National Aeronautics and Space Administration (NASA) is an independent agency of the United States Federal Government that succeeded the National Advisory Committee for Aeronautics (NACA). It is responsible for the civilian space program, as well as aeronautics and aerospace research. It’s vision is “To discover and expand knowledge for the benefit of humanity.””>NASA’s Lunar Reconnaissance Orbiter (LRO) spacecraft imaged SaturnSaturn is the sixth planet from the sun and has the second-largest mass in the Solar System. It has a much lower density than Earth but has a much greater volume. Saturn’s name comes from the Roman god of wealth and agriculture.”>Saturn on October 13, 2021. In this view, the Lunar Reconnaissance Orbiter Camera (LROC) was looking down at the north face of the rings, and from this perspective the rings in front of Saturn appear below its equator.

Saturn (enlarged 4x) seen from the Moon. Maneuvers such as this require intense planning from the LRO mission operations team at the NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Credit: NASA/GSFC/Arizona State University

The LROC Narrow Angle Cameras (NAC) are line scan cameras, which presents a challenge for imaging anything besides the Moon. This is because they were designed to acquire images by taking advantage of the motion of the spacecraft above the surface (LRO travels over 1,600 meters per second (1 mile per second) above the Moon), to build up an image one line at a time, with very short exposure times. To image Saturn, the spacecraft slews the NAC across Saturn, building up the image by mimicking our orbital ground motion. The slew across Saturn was achieved by pointing the NACs on one side of Saturn and then targeting the other side. LRO responded to the updated target by slewing to it at a specific rate across the planet. This rate is programmed to optimize LRO stability and speed and resulted in a NAC exposure time of 3.82 milliseconds. Since Saturn is much dimmer than the Moon (and JupiterJupiter is the largest planet in the solar system and the fifth planet from the sun. It is a gas giant with a mass greater then all of the other planets combined. Its name comes from the Roman god Jupiter.”>Jupiter) and the exposure time is in effect set by the slew speed, we cannot detect the Saturnian moons as we did with the Galilean moons, they are just too dim.

Fortunately, the NACs can image the amazing rings of Saturn, which are likely only 10 to 100 million years old, 10 meters thick, and are comprised almost entirely of water ice. The major rings visible here have a diameter of 270,000 km (168,000 miles), about 70% of the average distance between the Earth and the Moon.

Hubble’s 2021 look at Saturn shows rapid and extreme color changes in the bands of the planet’s northern hemisphere. Credit: NASA, ESA, A. Simon (NASA-GSFC), and M. H. Wong (UC Berkeley); Image Processing: A. Pagan (STScI)

For comparison, the image above was captured by the Hubble Space TelescopeThe Hubble Space Telescope (often referred to as Hubble or HST) is one of NASA’s Great Observatories and was launched into low Earth orbit in 1990. It is one of the largest and most versatile space telescopes in use and features a 2.4-meter mirror and four main instruments that observe in the ultraviolet, visible, and near-infrared regions of the electromagnetic spectrum. It was named after astronomer Edwin Hubble.”>Hubble Space Telescope during its grand tour of the outer solar system.

LRO is managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland, for the Science Mission Directorate at NASA Headquarters in Washington. Launched on June 18, 2009, LRO has collected a treasure trove of data with its seven powerful instruments, making an invaluable contribution to our knowledge about the Moon. NASA is returning to the Moon with commercial and international partners to expand human presence in space and bring back new knowledge and opportunities.