The fifth SpaceX cargo mission to the International Space Station under NASA’s Commercial Resupply Services contract now is scheduled to launch no earlier than 1:20 p.m. EST Friday, Dec. 19, from Space Launch Complex 40 at Cape Canaveral Air Force Station in Florida. NASA Television coverage of the launch begins at 12:15 p.m.
The change of launch date allows SpaceX to take extra time to ensure they do everything possible on the ground to prepare for a successful launch. Both the Falcon 9 rocket and its Dragon spacecraft are in good health.
The prelaunch news conferences also have moved to Thursday, Dec. 18 at the agency’s Kennedy Space Center in Florida. All briefings, which are subject to a change in time, will air live on NASA TV and the agency’s website.
The first briefing of the day will air at noon and will provide up-to-date information about the launch. Participants for the prelaunch briefing will be:
Mike Suffredini, NASA’s ISS Program manager
Hans Koenigsmann, vice president for Mission Assurance at SpaceX
Kathy Winters with the U.S. Air Force’s 45th Weather Squadron at Cape Canaveral Air Force Station in Florida
The second briefing, now at 1:30 p.m., will cover some of the numerous science investigations headed to the space station. Participants for the science briefing will be:
Julie Robinson, NASA’s ISS Program chief scientist
Michael Roberts, senior research pathway manager at the Center for the Advancement of Science in Space, headquartered in Melbourne, Florida
Cheryl Nickerson, Micro-5 principal investigator at Arizona State University
Samuel Durrance, NR-SABOL principal investigator at the Florida Institute of Technology in Melbourne
The final briefing, now at 3 p.m., will cover the Cloud-Aerosol Transport System (CATS) Earth science instrument headed to the space station. Participants for this briefing will be:
Julie Robinson, ISS Program chief scientist at NASA’s Johnson Space Center in Houston
Colleen Hartman, deputy director for science at NASA’s Goddard Space Flight Center in Greenbelt, Maryland
Robert J. Swap, program scientist with the Earth Science Division at NASA Headquarters in Washington
Matthew McGill, CATS principal investigator at Goddard
An on-time launch on Dec. 19 will result in the Dragon spacecraft arriving at the space station on Sunday, Dec. 21. Expedition 42 Commander Barry “Butch” Wilmore of NASA will use the station’s 57.7-foot robotic arm to reach out and capture it at about 6 a.m. Flight Engineer Samantha Cristoforetti of the European Space Agency will support Wilmore as they operate from the station’s cupola. NASA TV coverage of grapple will begin at 4:30 a.m. Coverage of Dragon’s installation to the Earth-facing port of the Harmony module will begin 9 a.m.
Artist's representation of the Transiting Exopanet Survey Satellite. 
On Wednesday at 6:51 p.m. local time (2251 ), a SpaceX  launched from  Air Force Base in Florida, United States, carrying, as a payload for the US National Aeronautics and Space Administration (NASA), the  (TESS).  NASA designed TESS to search for exoplanets circling stars mostly within 300 light-years of the .

Officially a NASA Astrophysics Explorer mission, much of the TESS program is to be run from the Massachusetts Institute of Technology's (MIT) Kavli Institute for Astrophysics and Space Research in cooperation with the . "One of the biggest questions in exoplanet exploration is: If an astronomer finds a planet in a star's habitable zone, will it be interesting from a biologist's point of view?" TESS principal investigator George Ricker told the press, "We expect TESS will discover a number of planets whose atmospheric compositions, which hold potential clues to the presence of life, could be precisely measured by future observers."

A little more than an hour after launch, NASA and SpaceX teams announced the satellite was up and functioning and had deployed its solar panels. Most launches have a roughly two-hour period during which the mission can be executed, but this one had a window of only thirty seconds because this satellite must use the Moon's gravity to reach the desired orbit.

TESS is slated to enter a high orbit distinct from the geosynchronous orbits used by many other satellites.  TESS instrument scientist Joel Villasenor, also of MIT, explained, "The Moon and the satellite are in a sort of dance. The Moon pulls the satellite on one side, and by the time TESS completes one orbit, the Moon is on the other side tugging in the opposite direction. The overall effect is the Moon's pull is evened out, and it's a very stable configuration over many years. Nobody's done this before, and I suspect other programs will try to use this orbit later on."

If all goes according to plan, TESS will circle the Earth for 60 days to establish its 13.7-day orbit and test its machinery before beginning its mission: using its four cameras to analyze stars for decreases in brightness that may be caused by a planet passing between us and them, a technique called the .  TESS's launch comes just as the , launched into orbit around the Sun 2009, is about to run out of fuel.  Scientists used Kepler to identify at least over 2300, perhaps over 4500 planets and gather data on stars and black holes.  TESS is designed to cover 400 times as much of the sky as Kepler, and is capable of viewing 85% of the sky.  Scientists expect it to find 1500 planets during its two-year mission, 300 Earth-like, but believe it may find many more.

Because TESS's cameras can cover a wide range of radiant energy, including infrared, scientists believe it may be able to detect planets orbiting , which scientists consider likely to host rocky, Earth-like planets with the right mass for an atmosphere and the right temperature to host liquid water, a range called the .

The data collected by TESS are to be publicly accessible so anyone who wishes may participate in the search. NASA plans to process the data, about 27 gigabytes collected per day, using a supercomputer called .

The original schedule had launch at 6:32 p.m. on Monday evening but it was postponed so the SpaceX team could perform more guidance navigation control tests before launch.

SpaceX is a private company that has partnered with NASA before on such missions as resupplying the International Space Station.



== Sources == 
*
*
*
*
*