Nasa's mission to find a new Earth (and say hi to aliens)

TESS - short for Transiting Exoplanet Survey Satellite - will search the sky to examine thousands of stars, sending vital information back to scientists on Earth to help them find planets that may be like our own.

According to the official NASA specs, TESS will find " thousands of exoplanets in orbit around the brightest stars in the sky" in its two-year survey of the galaxy. The media outlet is also broadcasting live coverage of the TESS launch, courtesy of the USA space agency.

Tess' four cameras will zoom in on red dwarf stars in our cosmic backyard an average 10 times closer than the Kepler-observed stars.

When finished, it's expected that TESS will have surveyed 85% of the visible sky on its planet-hunting mission.

Those are believed the most likely to feature rocky surfaces or oceans, and are thus considered the best candidates for life to evolve, as opposed to gas giants like Jupiter or Neptune. Will we ever find it?

TESS was encapsulated inside the Falcon 9 rocket's payload shroud last week in preparation for its transfer to SpaceX's rocket hangar at Cape Canaveral's Complex 40 launch pad.

One of the most important aspects of these exploratory space missions is for scientists to identify more planets that could potentially support life. From that vantage point, TESS will keep tabs on 200,000 of the brightest stars in our celestial neighborhood, looking for the telltale changes in brightness that result when a planet crosses over the star's disk. This allows among other things to deduce size, mass and orbit. As of this morning, more than 70 percent of the confirmed planets in NASA's Exoplanet Archive were found by the Kepler mission.

"TESS is created to image nearly all of the night sky - using four wide-angle cameras", Natalia Guerrero, an MIT scientist and researcher on the TESS mission, told UPI last week. There are far more planets in the Milky Way than there are stars.

The launch will be broadcast on NASA website or on its live YouTube stream which you will find below. "We know that planets in principle exist there", says Ricker, "but there's really not much more we can say other than that they exist". SpaceX indicated that the decision to skip a landing had to do with the fact that this particular Falcon 9 has already flown once before for another resupply mission to the space station in August.