Mercury for the Armchair Space Explorer

Mercury enhanced to study the first planet's geology. Credit: Nasa/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Amateurs can explore space - and contribute to science - from the comfort of their own homes thanks to the Internet, the power of personal computers, and space agencies’ open data policies. This post collects resources I’ve found that amateurs can use to explore the planet Mercury. This is the first in a series of posts about Armchair Space Exploration.

Citizen Science on Mercury

CosmoQuest and its Planet Mappers: Mercury project is the easiest way to both explore Mercury and contribute to planetary science. Volunteers circle craters in images of the planet captured by Nasa’s Messenger spacecraft. By crowdsourcing contributions from thousands of volunteers around the world, Planet Mappers: Mercury will create a catalog of millions of craters. Planetary scientists use crater catalogs to study surface geology as well as the 4.5 billion year evolution of planets. Automated software can scan images for craters, but struggle when craters overlap or when millennia of debris erodes crater walls.

Mercury Outreach

Space agencies have an obligation to explain their work to the public that pays for their work as well as to the students who will become the next generation of scientists. Space agencies take a mission-centric approach to their outreach programs, which means the number and quality of resources can vary dramatically. Outreach programs dedicated to the outer planets are few and far between, for example, while Mars with its fleet of European, Indian, and American spacecraft has robust, constantly updates programs for students and the public.

In the case of Mercury, most of the outreach programs are associated with Nasa’s Messenger mission (pictured above left during vibration testing) which will crash into Mercury later this spring after four years in orbit. Esa’s Bepi/Colombo spacecraft (pictured above right during thermal vacuum testing) won’t arrive at Mercury until 2024, so the BepiColombo outreach site is limited to background information about Mercury and the mission.

Johns Hopkins University Applied Physics Laboratory (JHU/APL) manages the Messenger mission for Nasa, so its site has most of the space agency’s Mercury outreach programs. Support has slowed as the mission winds down, but most of the information is current with the latest discoveries. Podcasts, brochures, and interactive features helps you understand how Mercury formed and learn about its unique features. Education modules let teachers bring the science of Mercury into the classroom. The iPhone app Messenger: Nasa’s Mission to Mercury consolidates the mission's facts, images, news and twitter feeds.

Nasa’s Solar System Exploration site consolidates facts and figures about Mercury. It also links to education outreach materials related to the first planet.

Mercury References

Few books dedicated to Mercury are both current with the latest discoveries and aimed at the public. Many of the Mercury-specific books were written by members of the Messenger science team for research libraries and scientists with expense accounts. This gallery highlights some of the most recent books dedicated to Mercury from the $35 Venus and Mercury and How to Observe Them to the $199 Dynamic Planet: Mercury in the Context of its Environment.

[Affiliate links support Small Steps to Space, but feel free to buy directly from your preferred bookseller.]

Free resources from Wikipedia, Nasa, and Nineplanets provide current facts and figures about Mercury. The mission page for Nasa’s Messenger and Esa’s science page for BepiColombo give good overviews of the spacecraft and instruments. Tagged articles from the Planetary Society and SpaceRef are good sources for the latest press releases and insider analysis of Mercury.

It’s easy to get Nasa press release images from the Planetary Photojournal’s Mercury search. You can download the images at different resolutions and get explanations of the science behind the image. The image below, for example, is the 1,500 kilometer wide Caloris Basin. It's a crater from an impact so powerful that it changed the opposite side of the planet. The enhanced color image shows the lava (in orange) that flooded the basin and the craters from later asteroid impacts.

Exploring Mercury

If you want to explore the full range of Mercury images yourself, you can go old school with Sky & Telescope’s globe of Mercury, but Google Earth gives you a 21st Century option. Download the datafile from the Messenger website and use Google Earth on your computer or smartphone to zoom over the planet’s surface. The Messenger scientists created tours that explain the many features and current theories about Mercury’s formation.

Shifting towards more professional tools, the Messenger QuickMap gives scientists - and the public - an easy way to view the mission’s images. It works a lot like Google Earth, but QuickMap’s advanced tools let you overlay data collected by Messenger’s other instruments, create 3D renderings, and map elevation changes. A simplified QuickMap on the Water-Ice Data Exploration site explains the discovery of Mercury's water ice in the permanently shadowed polar craters.

Sousa crater (upper left corner) and other impact sites on Mercury's northern hemisphere as seen in the Messenger Quickmap. Low elevations are shaded blue with higher elevations are shaded red. Source: Messenger QuickMap

Sousa crater (upper left corner) and other impact sites on Mercury's northern hemisphere as seen in the Messenger Quickmap. Low elevations are shaded blue with higher elevations are shaded red. Source: Messenger QuickMap

Using Data from Mercury

All of Nasa’s planetary missions must store their data in the space agency’s archives. Makes sense, right? It gives scientists a one-stop shop to download the data they need for their research. Nasa goes one step further and lets anyone access its Planetary Data System - since the American public paid for the data, after all, the data belong to the public. Public access, however, doesn’t make the PDS is easy to use. It’s main focus is supporting scientists. With a little skill, and an understanding of the Messenger spacecraft, the public can use the same tools scientists use to find data in the PDS. Esa's Planetary Science Archive will house data from BepiColombo after it arrives at Mercury in 2024

Nasa turned to the US Geological Survey’s map-creating experience to help plan the Apollo landings and USGS cartographers and astrogeologists have been mapping the Solar System ever since. The Planetary Image Locator Tool searches over 200,000 images from the Messenger and Mariner 10 missions that the USGS has mapped to a common coordinate system. Advanced options constrain the results based on date, camera filter, the angle of the Sun, and the orientation of the spacecraft.

Pilot, the USGS Planetary Image Locator Tool

Scientists at Arizona State University wanted an easier way to view data from the Lunar Reconnaissance Orbiter Camera. Commercial and scientific software developed to analyze images of Earth don’t work so well with images from other worlds. The LunaServ software now supports planetary images of Mercury. It’s designed to run on Linux, but Mac owners who know how to “installing dependencies” can run the software as well. An online demo version doesn’t have many features, but it does switch quickly between maps of the terrestrial planets and the larger moons of Jupiter and Saturn.

The most sophisticated search tools are hosted by the Planetary Data System’s subject nodes: the Geosciences Node at Washington University supports the Orbital Data Explorer while the Imaging Node at the Jet Propulsion Laboratory supports the Planetary Image Atlas. These aren’t for the general public, requiring special image processing software and an understanding of the technical aspects of the Messenger spacecraft.

Teacher and Student Exploration

The professional tools require some expertise, but that doesn’t mean they are out of amateurs’ reach. High school teachers and their students regularly use these tools to conduct scientific research.

The Student Planetary Investigator Program gives high school teachers and students hands-on experience with planetary science research. Student investigators learn how to use pro tools like the QuickMap, the USGS Planetary Image Locator Tool, and Nasa’s Planetary Data System. Then they conduct original research using data from the Messenger mission. Planetary scientists conduct webcasts to teach students how to use tools and understand the science of Mercury. This 2014 webcast, for example, explains how to use the QuickMap tool:

This paper (PDF) delivered at the 2015 Lunar and Planetary Science Conference reviews the impact that the Student Planetary Investigator Program’s hands-on, real-world research projects have on educational outcomes.