It is impossible to overstate how much more we can learn about other worlds when we visit them. Even from Earth’s orbit, where the atmosphere doesn’t interfere with picture quality, we just can’t see the same details.
I’m going to put some numbers on this. When the Europa Clipper mission reaches Juno in 2030, it will begin a series of flybys that bring it as close as 25 km from Europa’s surface. From a distance of 100km, a 1km feature on Europa’s surface will be half a degree across and appear as wide as the moon does from Earth. From Earth … that 1km feature appears 400 million times smaller and is beyond the physical limits of even our largest optical and infrared telescopes.
Since our last episode, NASA and ESA have launched 2 amazing missions on million mile journeys to see some of the smaller objects in our Solar System
Hera flies towards Didymos and Dimorphos
On October 7, with hurricane Milton spinning up off the west coast of Florida, the European Space Agency got in 1 final launch ahead of weather. The Hera mission launched on a Falcon 9 and headed straight away from Earth.
This mission is a follow-up to NASA’s DART mission and will let us see just what happened to the small asteroid-moon Dimorphus after it was purposely hit by the DART mission. DART was designed to test our ability to change asteroids orbits as we prepare to one day potentially protect our Earth from an incoming space rock. While we can see that Dimorphus’ orbit around the larger Didymos asteroid has indeed changed, we can’t see what literal impact the DART mission had on this binary asteroid system.
With Hera, we will finally get to see if a crater formed, if changes are visible on the main asteroid Didymos, and answer myriad other questions.
The journey to the asteroid belt is a long one.
In March 2025 Hera will fly past Mars, and train some of its scientific instruments on Mars’ moon Deimos. In addition to allowing new science to be done while testing Hera’s instruments, this side quest will also provide Hera with a velocity boost as it slingshots around the red planet.
If all goes well, Hera will catch up to Didymos and Dimorphos in October 2026, and in 2027 the mission will go all in on imaging and exploring Dimorphos, with the goal of making it one of the most studied objects in our Solar System.
Europa Clipper heads on a long journey to Jupiter
NASA’s Europa Clipper has been a long time in the making.
The 2011 Planetary Science Decadal Survey set out exploration of Jupiter’s large icy moon one of its highest priorities. Europa, with its ice covered oceans, is the most likely place in our Solar System to have present day life, and I think it is safe to say all of us in the space science community want to know if life exists beyond planet Earth.
NASA took the Decadal Survey’s recommendations to heart and in 2011 commissioned studies to explore what it would take to do a flyby mission, orbiter, or lander. Ultimately, we all had to acknowledge that we don’t have the capacity to sufficiently sterilize a lander and prevent Earth microbes from contaminating Europa. Instead, the safest way to study Europa and avoid potential contamination would be a mission capable of making multiple flybys of Europa as it orbited Jupiter.
In 2014, NASA began planning the Europa Multiple Flyby Mission. It would launch on the still-under-development SLS rocket on a direct to Jupiter trajectory that would see Clipper arriving at Jupiter in less than 3 years. Unfortunately, delays in the SLS program, and the needs of the Artemis program combined to make this impossible. In 2021, the mission looked for a commercial alternative and landed on the less powerful Falcon Heavy. With the help of gravitational assists from Earth and Mars, Clipper will be able to reach the Jupiter system in 5.5 years.
Currently, Europa Clipper is slated to arrive at Jupiter in June 2030.
From commissioning designs in 2011, to arriving in 2030, to finally making a fly by of Europa in 2031, this is a generation-defining mission.
And NASA has made sure Clipper will be worth the wait.
To be very clear – Clipper isn’t carrying the kinds of instruments that are needed to detect life. I can’t look for fragments of RNA or DNA. It doesn’t have the kinds of microscopes that could look for cells if it happened to catch a large enough sample. Clipper is not a life detection machine. Clipper is instead looking for the stuff needed for life – the organic molecules that are the basis of bodies and food for life on Earth.
If we can find the requirements for life, then Clippers maps Europa’s surface and structure will allow us to develop future missions that should be able to directly look for life.
We have so much planning to do before we can look for life. And that planning is taking place here on Earth. Researchers are developing the autonomous ocean explorers and testing different technologies both in the high pressure depths of Earth’s oceans and in the dark and barely accessible sink holes and subsurface waters of South America. We still need to sort how we cut through the ice, get a signal from beneath the ice, and sterilize a mission… but all of that will come with time… and money.
For now, we wait.
Europa Clipper has successfully deployed it’s longer than-a basketball court solar panels, and is communicating with NASA’s Deep Space Network. As we hear more from the mission, we’ll keep you updated.