A small fuel leak on one of the CubeSats has forced its engineers to creatively compensate, angling the spacecraft so the leak pushes in the desired trajectory, says Joel Krajewski, MarCO's project manager at JPL.
"We have assumed. From what we know of the structure of the Earth, we think that Mars is a terrestrial planet formed in much the same way". After months and months of travel from Earth the InSight lander is now poised to enter the martian atmosphere and touch down on the dusty surface.
After more than six months in transit, a probe managed by Pasadena-based Jet Propulsion Laboratory successfully touched down on the surface of Mars Monday, beginning the first mission created to study the center of the Red Planet.
Watch a livestream of the landing below, courtesy of NASA's Jet Propulsion Lab.
The mission may seem specialized, but these two pieces of information-seismic activity and heat energy-can tell scientists a great deal about the history of Mars.
The NASA Viking probes of the mid-1970s were equipped with seismometers, too, but they were bolted to the top of the landers, a design that proved largely ineffective. It landed less than 400 miles (600 kilometers) from NASA's Curiosity rover, which until Monday was the youngest working robot in town. That means slowing down from 12,300 miles per hour as it enters the Martian atmosphere to a complete stop on the ground 6.5 minutes later.
Earth's success rate at Mars is just 40 percent, counting every attempted flyby, orbital flight and landing by the US, Russia and other countries dating back to 1960.
The landing should occur just before 3 p.m. EST, and shortly after, InSight is scheduled to send two landing confirmation signals seven minutes apart, indicating that it has touched down safe and sound.
In our solar system family, Mars is Earth's next of kin, the next-door relative that has captivated humans for millennia.
Launched from Vandenberg Air Force Base in California, the exploratory droid began its mission way back on May 5.
"Our team will measure the heat coming through the surface of Mars, as well as the level of heat retained".
The landing will be streamed live on NASA's official YouTube presence.
InSight is designed as the first mission to study and learn about the deep interiors of the red planet.
The InSight lander is aiming for a Monday afternoon touchdown on what scientists and engineers hope will be a flat plain.
A full list of these events can be found on Nasa's website, here.
After landing on Mars, InSight will spread its solar panels, unfold a robotic arm, and stay put.
The first image from the surface of Mars is expected at 2004 GMT. "This is a very hard activity that has to be done automatically by the lander", he said. The agency also will get its first clear images of the spacecraft's landing site - a vast, flat, nearly featureless plain near the equator. It is also carrying a seismometer to monitor earthquakes, as Nasa attempts to answer "fundamental questions about the formation of Earth-like planets". Unlike InSight, the MarCO spacecraft keep on going past Mars into space. Signals will come from various sources - the lander during descent; two experimental briefcase-sized spacecraft called MarCOs that flying behind InSight; InSight itself after landing; the Mars Reconnaissance Orbiter (MRO) spacecraft during descent; the 2001 Mars Odyssey after InSight's touchdown.