Messenger Satellite: A trip to Mercury

The National Aeronautics and Space Administration (NASA) has done numerous missions since its founding in 1958 with a success rate of 17% which is the second-highest across all the 11 agencies. Over the course of 60+ years, NASA has had many successful missions, but there are a few that have kind of been forgotten, because of all the NASA news bombarding us every day. The mission which is the focus of this article is known as the messenger satellite mission. Continue reading this article to learn all about the mission and its importance.

Messenger Satellite: An overview

The Messenger Satellite launched by NASA was to study the surface of Mercury. MESSENGER stands for Mercury Surface, Space Environment, Geochemistry, and Ranging. It was the first-ever spacecraft to orbit Mercury and was the seventh discovery-class mission. Before Messenger, the mariner 10 had visited Mercury but those were just fly-bys. The main goal to achieve through the Messenger satellite was to study the geology, magnetic field, and chemical composition of the planet. 

It was launched on 3^rd August 2004 from  Cape Canaveral Air Force Station in Florida aboard the Delta II 7925 rocket and after a set of very complex flybys around Earth (once), Venus (twice), and Mercury itself ( Thrice ), it entered Mercury’s orbit on March 18^th, 2011. Its mission began on April 4^th, 2011 and its primary mission was completed in less than a year on March 17^th, 2012 by collecting almost 100,000 images of the terrestrial planet. Messenger achieved 100% of Mercury a year later on March 6^th, 2013. Then after completing its second extended mission which lasted for over two years, Messenger was deorbited letting it impact the surface of Mercury on April 30^th, 2015, against the planet it had been orbiting for the last 4 years.

Messenger Satellite: Objectives

The Messenger satellite had been launched by NASA for the study of the characteristics and environment of Mercury from orbit. To put it more precisely, it had the following objectives:

• To determine the chemical composition of Mercury’s surface.
• To study its geology.
• To study its magnetic field.
• To study the planet’s core, its size, and its shape.
• to study Mercury’s exosphere.

Messenger Satellite: Findings

The Messenger Satellite, in its 4 year journey orbiting Mercury had many major findings. They are as follows:

• Water was discovered in the exosphere of the planet.
• Found visual evidence of historical volcanic activities.
• Evidence for the liquid iron planetary core.
• Discovered carbon-containing organic compounds and water ice inside permanently shadowed craters near the north pole.

Little known facts about Mercury

• Mercury is so close to the Sun that it’s up to 11 times brighter there than here on Earth.
• The Mariner 10 did 3 fly-bys of Mercury but unfortunately captured the same side all three times.
• Mercury is the planet closest to the sun but still houses ice caps. This is because of its weird axis of rotation which allows some crater parts to always be in the shade which allows it to have ice on the closest planet.
• The total operational time of the Messenger satellite from launch till impact against Mercury was 10 years 8 months 26 days 13 hours 10 minutes and 3 seconds.
• Messenger satellites helped in the construction of the most detailed and accurate map of Mars to date ( 2022 ).
• Even after the Messenger Satellite ran out of propellant for course correction in 2014, its operation was extended for several months by using the helium gas to pressurise the tank as reaction mass. 
• Mercury is the closest planet to the sun but it is not the hottest planet in our solar system. The hottest planet in our solar system is Venus.

FAQ’s about Mercury