NASA

Already poised to break the record for cumulative time spent in space by a U.S. astronaut, Peggy Whitson is set to extend her mission with an additional three months at the International Space Station.

NASA and the Russian space agency Roscosmos, signed an agreement to extend Peggy Whitson’s stay on the space station into Expedition 52. Rather than returning to Earth with her Expedition 51 crew mates Oleg Novitsky of Roscosmos and Thomas Pesquet of ESA (European Space Agency), in June as originally planned, Whitson will remain on the space station and return home with NASA’s Jack Fischer and Roscosmos’ Fyodor Yurchikhin. That landing is targeted for September.

“This is great news,” Whitson said. “I love being up here. Living and working aboard the space station is where I feel like I make the greatest contribution, so I am constantly trying to squeeze every drop out of my time here. Having three more months to squeeze is just what I would wish for.”

The arrangement takes advantage of a Soyuz seat left empty by the Roscosmos decision to temporarily reduce their crew complement to two cosmonauts. Whitson’s extension will ensure a full complement of six astronauts on board the station and increase the amount of valuable astronaut time available for experiments on board the station.

“Peggy’s skill and experience makes her an incredible asset aboard the space station,” said Kirk Shireman, NASA’s International Space Station Program Manager. “By extending the stay of one of NASA’s most veteran astronauts, our research, our technology development, our commercial and our international partner communities will all benefit.”

This is Whitson’s third long-duration stay onboard the space station. She launched on Nov. 17 with 377 days in space already under her belt, and on April 24 will break Jeff Williams’ standing United States record of 534 cumulative days in space. In 2008, Whitson became the first woman to command the space station, and on April 9 will become the first woman to command it twice. In addition, she holds the record for most spacewalks by a female.

Follow Whitson’s stay on the space station via social media at:

http://www.twitter.com/AstroPeggy

SOURCE: NASA

Three crew members aboard the International Space Station are scheduled to depart the orbiting outpost Monday, April 10. Coverage of their departure and return to Earth will air on NASA Television and the agency’s website.

Expedition 50 Commander Shane Kimbrough of NASA and Flight Engineers Sergey Ryzhikov and Andrey Borisenko of Roscosmos will undock their Soyuz MS-02 spacecraft from the space station at 4 a.m. EDT and land in Kazakhstan at 7:20 a.m. (5:20 p.m.Kazakhstan time). Their return will wrap up 173 days in space for the crew members since their launch last October.

NASA TV will air coverage of the departure and landing activities at the following dates and times:

Sunday, April 9

• 10:40 a.m. – Change of command ceremony in which Kimbrough hands over station command to NASA’s Peggy Whitson

Monday, April 10

• 12:15 a.m. – Farewell and hatch closure coverage (hatch closure at 12:40 a.m.)
• 3:30 a.m. – Undocking coverage (undocking scheduled at 4 a.m.)
• 6 a.m. – Deorbit burn and landing coverage (deorbit burn at 6:27 a.m., landing at 7:20 a.m.)
• 9 a.m. – Video file of hatch closure, undocking and landing activities.

Tuesday, April 11

• 12 p.m. – Video file of landing and post-landing activities and post-landing interview with Kimbrough in Kazakhstan

Together, the Expedition 50 crew members continued work on hundreds of experiments in biology, biotechnology, physical science and Earth science aboard humanity’s only orbital laboratory.

At the time of undocking, Expedition 51 will begin aboard the station under Whitson’s command. Along with her crewmates Oleg Novitskiy of Roscosmos and Thomas Pesquet of ESA (European Space Agency), the three-person crew will operate the station until the arrival of two new crew members. NASA’s Jack Fischer and Fyodor Yurchikhin of Roscosmos are scheduled to launch April 20 from Baikonur, Kazakhstan.

Keep up with the International Space Station, and its research and crews, at:

 https://www.nasa.gov/station

SOURCE: NASA

NASA’s Cassini spacecraft, in orbit around Saturn since 2004, is about to begin the final chapter of its remarkable story. On Wednesday, April 26, the spacecraft will make the first in a series of dives through the 1,500-mile-wide (2,400-kilometer) gap between Saturn and its rings as part of the mission’s grand finale.

“No spacecraft has ever gone through the unique region that we’ll attempt to boldly cross 22 times,” said Thomas Zurbuchen, associate administrator for the Science Mission Directorate at NASA Headquarters in Washington. “What we learn from Cassini’s daring final orbits will further our understanding of how giant planets, and planetary systems everywhere, form and evolve. This is truly discovery in action to the very end.”

During its time at Saturn, Cassini has made numerous dramatic discoveries, including a global ocean that showed indications of hydrothermal activity within the icy moon Enceladus, and liquid methane seas on its moon Titan.

Now 20 years since launching from Earth, and after 13 years orbiting the ringed planet, Cassini is running low on fuel. In 2010, NASA decided to end the mission with a purposeful plunge into Saturn this year in order to protect and preserve the planet’s moons for future exploration – especially the potentially habitable Enceladus.

But the beginning of the end for Cassini is, in many ways, like a whole new mission. Using expertise gained over the mission’s many years, Cassini engineers designed a flight plan that will maximize the scientific value of sending the spacecraft toward its fateful plunge into the planet on Sept. 15. As it ticks off its terminal orbits during the next five months, the mission will rack up an impressive list of scientific achievements.

“This planned conclusion for Cassini’s journey was far and away the preferred choice for the mission’s scientists,” said Linda Spilker, Cassini project scientist at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California. “Cassini will make some of its most extraordinary observations at the end of its long life.”

The mission team hopes to gain powerful insights into the planet’s internal structure and the origins of the rings, obtain the first-ever sampling of Saturn’s atmosphere and particles coming from the main rings, and capture the closest-ever views of Saturn’s clouds and inner rings. The team currently is making final checks on the list of commands the robotic probe will follow to carry out its science observations, called a sequence, as it begins the finale. That sequence is scheduled to be uploaded to the spacecraft on Tuesday, April 11.

Cassini will transition to its grand finale orbits, with a last close flyby of Saturn’s giant moon Titan, on Saturday, April 22. As it has many times over the course of the mission, Titan’s gravity will bend Cassini’s flight path. Cassini’s orbit then will shrink so that instead of making its closest approach to Saturn just outside the rings, it will begin passing between the planet and the inner edge of its rings.

“Based on our best models, we expect the gap to be clear of particles large enough to damage the spacecraft. But we’re also being cautious by using our large antenna as a shield on the first pass, as we determine whether it’s safe to expose the science instruments to that environment on future passes,” said Earl Maize, Cassini project manager at JPL. “Certainly there are some unknowns, but that’s one of the reasons we’re doing this kind of daring exploration at the end of the mission.”

In mid-September, following a distant encounter with Titan, the spacecraft’s path will be bent so that it dives into the planet. When Cassini makes its final plunge into Saturn’s atmosphere on Sept. 15, it will send data from several instruments – most notably, data on the atmosphere’s composition – until its signal is lost.

“Cassini’s grand finale is so much more than a final plunge,” said Spilker. “It’s a thrilling final chapter for our intrepid spacecraft, and so scientifically rich that it was the clear and obvious choice for how to end the mission.”

Resources on Cassini’s grand finale, including images and video, are available at:

https://saturn.jpl.nasa.gov/mission/grand-finale/grand-finale-resources

SOURCE: NASA