Inside NASA’s Kennedy Space Center in Florida as the SpaceX payload fairing containing TESS is moved by crane to a transporter. Image: NASA/Kim Shiflett

NASA is set to launch its latest satellite, called TESS, aboard a SpaceX rocket with one mission: locate distant worlds that could harbour alien life.

NASA has been told it has to wait until 18 April for the launch of its latest satellite – the Transiting Exoplanet Survey Satellite (TESS) – after ground crew identified that further guidance, navigation and control analysis had to be done.

Aboard SpaceX’s Falcon 9 rocket, the Monday (16 April) launch of TESS was aborted in the final hours as the company looked to make absolutely sure it avoids any costly catastrophe.

Coverage of the launch has garnered particular attention, but what exactly is TESS and what does it hope to achieve?

Here are four things you need to know about what could be an important scientific mission.

1. What it aims to do

The TESS satellite aims to take on board what has been achieved by the exoplanet-hunting spacecraft Kepler and improve it exponentially by directly searching for alien worlds in greater detail.

After all, Kepler was limited by the hardware on board, meaning it could only observe a small fraction of what was out there, with many of the stars too faint to detect the surrounding planets with great accuracy.

The spacecraft will spend the next two years observing 200,000 of the brightest points in the night’s sky, with the NASA team hopeful that by the time the mission is over, it will have found 20,000 exoplanets, of which 500 might be Earth-sized.

2. NASA hitches ride aboard SpaceX in major first

SpaceX will feel vindicated following a recent investigation finding it devoid of blame in the loss of the secret Zuma satellite in January, but NASA scientists will still be feeling slightly anxious with the launch of TESS.

In a major landmark for the space agency, this is the first of its missions to be launched by a SpaceX rocket.

The $200m piece of hardware was given the go-ahead to launch aboard the Falcon 9 rocket by NASA’s administrators only as recently as February.

Adding to the anxiety will be the fact that TESS will be put into an orbit never attempted before, out as far as the moon and back to Earth, lasting 14 days at a time.

TESS in space

NASA’s newest planet hunter, TESS, will look around the brightest stars closest to our solar system for new worlds. Image: NASA’s Goddard Space Flight Center

3. Astronomers dying to get their hands on the data

Once the planets are identified, the world’s astronomers can adjust all of their equipment – including the long-delayed James Webb Space Telescope – and analyse the planets in great detail to determine whether they could harbour life.

When active, TESS will collect 27GB of scientific data every day before being put through NASA’s specialist algorithms, which are designed to clean up the signal to remove any background interference.

Stephen Rinehart, TESS’s project scientist, said of the mission: “There are some people on the mission who are very, very, very keen to find Earth-sized planets in the habitable zones of their host stars, and that would be absolutely fabulous.

“But the data on all these planets is interesting, because they help us form a picture of how planetary systems form and evolve. It’s going to be a game-changer in our ability to study planets.”

4. A one-two punch of satellite discovery

The launch of TESS will be immediately beneficial to scientists down here on Earth, but the satellite will also lay the groundwork for future missions, most notably the European Space Agency’s Atmospheric Remote-sensing Infrared Exoplanet Large-survey (ARIEL) spacecraft.

Set for launch in 2028, ARIEL – with the location of thousands of exoplanets discovered by TESS – will be able to ‘sniff’ their atmospheres to determine their chemical composition and answer the question: how do planetary systems form and evolve?

During its four-year mission, ARIEL will observe 1,000 planets, ranging from Jupiter and Neptune down to super-Earth size, in the visible and the infrared with its metre-class telescope.

All of these factors should lead to a bounty of information returned to Earth, dependent on whether SpaceX can get the craft to its intended orbit.