NARRATOR: The next component in NASA's network of vital communications satellites will be
placed into space this month to continue the task of relaying data and commands from Earth
to the space agency's fleet of spacecraft.
Thirty years into its operations, the Tracking and Data Relay Satellite System has allowed
NASA to expand its abilities to communicate directly with human spacecraft like the International
Space Station and unmanned observatories such as the Hubble Space Telescope while being
able to forgo its network of ground-based communications stations around the world.
TIM DUNN: The TDRS constellation brings back all of the data and video that we see every
day from the International Space Station.
In addition, TDRS supports all of the data from the Hubble Space Telescope and all of
our low Earth orbit NASA science missions.
NARRATOR: In other words, TDRS accomplished exactly what NASA designed it for.
Its work is far from finished however, and NASA's needs are not shrinking.
That's why the agency is launching TDRS-L, the next member of the third-generation of
TDRS satellites.
TDRS-L will sustain the TDRS constellation and it will add to this national capability.
NARRATOR: Like its predecessors, TDRS-L carries the iconic look of two large, parabolic antennas
and a set of solar panels.
Those antennas, each 15 feet in diameter, provided the launch processing teams with
a bit of a challenge since there is a limited amount of time they can stay folded and still
unfurl to their proper shape.
The processing teams kept close track of the time they were folded and had plans ready
in case the antennas had to be opened if there was a lengthy launch delay.
Identical to TDRS-K, which was launched in 2013, TDRS-L will take its station in geosynchronous
orbit more than 22,300 miles above Earth.
From there it can basically hover over a point on Earth and communicate with every satellite
and spacecraft below it, along with NASA's ground stations and other TDRS satellites.
Working in conjunction with the seven other operational TDRS platforms already in space,
TDRS-L lets NASA stay in touch with its Earth-circling spacecraft at all times.
In fact, TDRS spacecraft already in operation will help track this newest member of the
family as it climbs from Cape Canaveral Air Force Station in Florida to its new home in
space aboard an Atlas V rocket.
DUNN: If you only had antennas in Africa, the middle of the Indian Ocean and Australia,
you are generally faced with coverage gaps, but when you are looking down from the geostationary
orbit of the TDRS constellation, you're able to seamlessly cover the entire period of a
launch vehicle trajectory.
NARRATOR: The United Launch Alliance Atlas V rocket that will power the 7,600-pound TDRS-L
off the launch pad and to its orbit location arrived at Cape Canaveral in October to begin
a couple months of processing.
DIANA CALERO: Luckily, TDRS-L has been a very smooth flow.
TDRS-K which also was a smooth flow but it was kind of the first time we had launched
about 10 years a TDRS satellite.
/// So we were able to apply a lot of the lessons learned from the TDRS-K flow to the
TDRS-L.
NARRATOR: The Atlas V, which includes a venerable Centaur upper stage, is relatively new to
NASA's launch catalog, but has taken on the mantle of NASA's workhorse booster.
In recent years it sent probes to Jupiter, Mars and the moon.
CALERO: Although it is very reliable and very successful, we always, we don't change the
way we go into a launch campaign or a mission.
We have very strict requirements.///(15:21 -) So although we are very successful, we
don't diminish our involvement in any way shape or form.
We always give it the same amount of rigor whether it's the first second or fiftieth.
NARRATOR: While the Atlas V is a newer booster, the Centaur is celebrating its 50th year in
service.
Developed at NASA's Glenn Research Center in Ohio, the Centaur was the first to use
liquid hydrogen for fuel in a mix with liquid oxygen.
Its success paved the way for later hydrogen-fueled engines including those on the second and
third stages of the Saturn V rocket, and the space shuttle main engines.
Launch day is Jan. 23 for the TDRS-L. For the launch team and those who built and processed
the spacecraft, it will be a testing time, which is normal for every launch day no matter
the mission.
CALERO: The last four minutes when you're going into terminal count, it's just one after
another.
You don't have a whole lot of time, you don't have time to stop and start doing things and
troubleshooting, it's very intense.
DUNN: I've been tremendously lucky to have a highly capable team.
The United Launch Alliance and Launch Services Program team is just exemplary, I couldn't
ask for anything better.
And in that regard, I like to make sure the team as a whole is focused on launch day,
that we're ready for the countdown, that we've done all the steps necessary leading up to
launch day that will ensure a flawless execution and mission success.