Artist impression of Tess alongside a rather unlikely configuration of planets around a star
Illustration: NASA

Update, April 18, 7:05pm: NASA launched the TESS spacecraft from Cape Canaveral, Florida at 6:51pm local time, hitting its 30-second launch window.

GIF: YouTube

The first stage of the SpaceX Falcon 9 rocket successfully landed on a drone ship in the Atlantic ocean. It marked the 24th time the company has successfully recovered one of its rockets, according to Spaceflight Now. You can watch the landing (until the camera cuts out) below:

GIF: YouTube

On the NASA broadcast, NASA public affairs officer Marie Lewis said that TESS will embark on a two-year mission, during which it will use its camera systems to break up the sky into 26 different sections. It will examine each section for about one month and will monitor more than 200,000 stars, looking for changes in brightness that could signal “a planet crossing over.”

TESS will cover an area of sky 350 times larger than Kepler, space observatory launched by NASA in 2009 to discover Earth-size planets orbiting other stars. It will also look at stars up to 100 times brighter than those that Kepler studied, which will show planets closer to our solar system. Scientists expect to find about 300 planets about the same size or up to two times as large as Earth, Lewis explained.

Dr. Martin Still, TESS program scientist, said that the Kepler mission revealed that there are planets “all over the place” in the galaxy. TESS will allow NASA to “do a survey of the nearest planets around the nearest stars.”

“Kepler, because of the nature of its survey … you’ll notice that there’s not so much of a story after the original detection because those planets are so far away, we can’t follow up and do more science,” Still explained on the broadcast. “With TESS, these stars and planets are so much closer, we can find atmospheres around these planets, characterize the constituents of those atmospheres. So the stories of these planets will continue on long after detection.”

Still said, “It’s our human nature to understand what the universe is. It’s our human nature to understand where we came from, where we are going, and of course, are we alone?”


It will take TESS two months to months to reach its orbit.

Original post below:

After scrubbing Monday’s launch, the SpaceX Falcon 9 rocket holding NASA’s TESS spacecraft is vertical and ready for takeoff this evening.


We’re all pretty excited about the Transiting Exoplanet Survey Satellite, or TESS. The teeny satellite will serve as the Kepler/K2 mission’s replacement and will survey hundreds of thousands of stars in the 300 closest light-years to Earth. Weather conditions at Florida’s Kennedy Space Center are 90 percent favorable for today’s launch.

Countdown clocks were stopped and buses full of spectators were turned around after Monday’s launch was scrapped. SpaceX reported that they’d chosen to perform more guidance navigation and control analysis on their rocket,

Today’s 30-second launch window begins at 6:51 pm ET. You’ll be able to watch takeoff live below, with coverage beginning at 6:30 pm ET.

We’ve written a lot about TESS and the quest to find Earth 2.0. TESS will scan for interesting candidates for follow-up studies by future telescopes, like the powerful James Webb Space Telescope that is scheduled for launch in 2020. TESS will particularly look at stars that are brighter and/or closer than the ones Kepler spotted. One kind of exoplanet of special interest is the sort that orbits red dwarfs, like TRAPPIST-1 and Proxima Centauri. These exoplanets seem both abundant and frequently located in places where liquid water could exist on their surface.


We’ve got our fingers crossed for a successful launch today. The TESS mission will be especially crucial once the beloved Kepler spacecraft runs out of fuel and goes silent, which is expected to happen in the next few months.