By
updated 10/29/2011 12:33:53 PM ET 2011-10-29T16:33:53

The outcome of an unmanned Russian supply spaceship launch to the International Space Station on Sunday will determine whether the station remains fully staffed in the upcoming months.

The Progress 45 cargo vessel is slated to blast off from Kazakhstan at 6:11 a.m. ET Sunday. If anything goes wrong with the flight, the launch of three new station crewmembers — currently scheduled for Nov. 14 — would likely be delayed, because both missions use similar Russian Soyuz rockets.

And if the manned mission is delayed by more than five days or so, the station could be left without a crew for the first time in more than a decade, because the three spaceflyers currently aboard are due to come home on Nov. 22.

Russian rocket crash
The immediate outlook for the space station is unclear in the wake of the Aug. 24 crash of the Progress 44 supply vessel, which was also en route to the orbiting lab. Progress 44 slammed into the Siberian dirt after the third stage of its Soyuz rocket failed. [ Photos: Russia's Lost Cargo Ship Progress 44 ]

"The Soyuz FG booster used to launch the Soyuz TMA crew vehicles is a variant of the Soyuz U which experienced the failure," Thomas Stafford, chairman of NASA's International Space Station Advisory Committee, wrote in testimony to the House of Representatives' Committee on Science, Space and Technology earlier this month.

As a result, the manned Soyuz mission to the orbiting lab originally scheduled for Sept. 21 was pushed back considerably, to the middle of November.

"Its launch resumption will be dependent on the successful Soyuz U launch of Progress 45P on October 30th," Stafford added.

Stafford said he had every confidence that the Progress 45 launch would go smoothly. The Russians appear to have identified the problem that doomed Progress 44 and have instituted quality-control measures that should prevent it from happening again, other NASA officials have said.

An unmanned space station?
The space station has been continously staffed since November 2000. Bill Gerstenmaier, associate administrator for NASA's human exploration and operations directorate, told the same House committee that the chances of this streak being broken in mid-November are remote.

But if it does happen, the orbiting lab would probably not fall out of the sky while waiting for astronauts to arrive once again. NASA officials have said that the station can be operated efficiently from the ground for a while.

"The ability to get to higher orbit and to get an extended period of operation — even in an unmanned status if necessary — for one year to as much as two years is noted with some good comfort," Joseph Dyer, chairman of NASA's Aerospace Safety Advisory Panel, told the House committee.

NASA and its international partners would, of course, prefer to keep the station manned continuously, and at its full capacity of six spaceflyers if possible.

Crewmembers perform maintenance work and can troubleshoot problems that may crop up. And more scientific experiments can get done with more spaceflyers onboard — a key priority now that assembly of the station is done and it's coming into its own as a research facility, NASA officials have said.

You can follow SPACE.com senior writer Mike Wall on Twitter:@michaeldwall. Follow SPACE.com for the latest in space science and exploration news on Twitter@Spacedotcomand onFacebook.

© 2013 Space.com. All rights reserved. More from Space.com.

Photos: Month in Space: January 2014

loading photos...
  1. Southern stargazing

    Stars, galaxies and nebulas dot the skies over the European Southern Observatory's La Silla Paranal Observatory in Chile, in a picture released on Jan. 7. This image also shows three of the four movable units that feed light into the Very Large Telescope Interferometer, the world's most advanced optical instrument. Combining to form one larger telescope, they are greater than the sum of their parts: They reveal details that would otherwise be visible only through a telescope as large as the distance between them. (Y. Beletsky / ESO) Back to slideshow navigation
  2. A balloon's view

    Cameras captured the Grandville High School RoboDawgs' balloon floating through Earth's upper atmosphere during its ascent on Dec. 28, 2013. The Grandville RoboDawgs’ first winter balloon launch reached an estimated altitude of 130,000 feet, or about 25 miles, according to coaches Mike Evele and Doug Hepfer. It skyrocketed past the team’s previous 100,000-feet record set in June. The RoboDawgs started with just one robotics team in 1998, but they've grown to support more than 30 teams at public schools in Grandville, Mich. (Kyle Moroney / AP) Back to slideshow navigation
  3. Spacemen at work

    Russian cosmonauts Oleg Kotov, right, and Sergey Ryazanskiy perform maintenance on the International Space Station on Jan. 27. During the six-hour, eight-minute spacewalk, Kotov and Ryazanskiy completed the installation of a pair of high-fidelity cameras that experienced connectivity issues during a Dec. 27 spacewalk. The cosmonauts also retrieved scientific gear outside the station's Russian segment. (NASA) Back to slideshow navigation
  4. Special delivery

    The International Space Station's Canadian-built robotic arm moves toward Orbital Sciences Corp.'s Cygnus autonomous cargo craft as it approaches the station for a Jan. 12 delivery. The mountains below are the southwestern Alps. (NASA) Back to slideshow navigation
  5. Accidental art

    A piece of art? A time-lapse photo? A flickering light show? At first glance, this image looks nothing like the images we're used to seeing from the Hubble Space Telescope. But it's a genuine Hubble frame that was released on Jan. 27. Hubble's team suspects that the telescope's Fine Guidance System locked onto a bad guide star, potentially a double star or binary. This caused an error in the tracking system, resulting in a remarkable picture of brightly colored stellar streaks. The prominent red streaks are from stars in the globular cluster NGC 288. (NASA / ESA) Back to slideshow navigation
  6. Supersonic test flight

    A camera looking back over Virgin Galactic's SpaceShipTwo's fuselage shows the rocket burn with a Mojave Desert vista in the background during a test flight of the rocket plane on Jan. 10. Cameras were mounted on the exterior of SpaceShipTwo as well as its carrier airplane, WhiteKnightTwo, to monitor the rocket engine's performance. The test was aimed at setting the stage for honest-to-goodness flights into outer space later this year, and eventual commercial space tours.

    More about SpaceShipTwo on PhotoBlog (Virgin Galactic) Back to slideshow navigation
  7. Red lagoon

    The VLT Survey Telescope at the European Southern Observatory's Paranal Observatory in Chile captured this richly detailed new image of the Lagoon Nebula, released on Jan. 22. This giant cloud of gas and dust is creating intensely bright young stars, and is home to young stellar clusters. This image is a tiny part of just one of 11 public surveys of the sky now in progress using ESO telescopes. (ESO/VPHAS team) Back to slideshow navigation
  8. Fire on the mountain

    This image provided by NASA shows a satellite view of smoke from the Colby Fire, taken by the Multi-angle Imaging SpectroRadiometer aboard NASA's Terra spacecraft as it passed over Southern California on Jan. 16. The fire burned more than 1,863 acres and forced the evacuation of 3,700 people. (NASA via AP) Back to slideshow navigation
  9. Where stars are born

    An image captured by NASA's Spitzer Space Telescope shows the Orion Nebula, an immense stellar nursery some 1,500 light-years away. This false-color infrared view, released on Jan. 15, spans about 40 light-years across the region. The brightest portion of the nebula is centered on Orion's young, massive, hot stars, known as the Trapezium Cluster. But Spitzer also can detect stars still in the process of formation, seen here in red hues. (NASA / JPL-Caltech) Back to slideshow navigation
  10. Cygnus takes flight

    Orbital Sciences Corp.'s Antares rocket rises from NASA's Wallops Flight Facility on Wallops Island, Va, on Jan. 9. The rocket sent Orbital's Cygnus cargo capsule on its first official resupply mission to the International Space Station. (Chris Perry / NASA) Back to slideshow navigation
  11. A long, long time ago...

    This long-exposure picture from the Hubble Space Telescope, released Jan. 8, is the deepest image ever made of any cluster of galaxies. The cluster known as Abell 2744 appears in the foreground. It contains several hundred galaxies as they looked 3.5 billion years ago. Abell 2744 acts as a gravitational lens to warp space, brightening and magnifying images of nearly 3,000 distant background galaxies. The more distant galaxies appear as they did more than 12 billion years ago, not long after the Big Bang. (NASA / NASA via AFP - Getty Images) Back to slideshow navigation
  12. Frosty halo

    Sun dogs are bright spots that appear in the sky around the sun when light is refracted through ice crystals in the atmosphere. These sun dogs appeared on Jan. 5 amid brutally cold temperatures along Highway 83, north of Bismarck, N.D. The temperature was about 22 degrees below zero Fahrenheit, with a 50-below-zero wind chill.

    Slideshow: The Year in Space (Brian Peterson / The Bismarck Tribune via AP) Back to slideshow navigation
  1. Editor's note:
    This image contains graphic content that some viewers may find disturbing.

    Click to view the image, or use the buttons above to navigate away.

  2. Editor's note:
    This image contains graphic content that some viewers may find disturbing.

    Click to view the image, or use the buttons above to navigate away.

  3. Editor's note:
    This image contains graphic content that some viewers may find disturbing.

    Click to view the image, or use the buttons above to navigate away.

  4. Editor's note:
    This image contains graphic content that some viewers may find disturbing.

    Click to view the image, or use the buttons above to navigate away.

Discuss:

Discussion comments

,

Most active discussions

  1. votes comments
  2. votes comments
  3. votes comments
  4. votes comments