Featured Research

from universities, journals, and other organizations

Hubble Telescope Placed Into Safe Hold As Gyroscope Fails

Date:
November 16, 1999
Source:
National Aeronautics And Space Administration
Summary:
NASA's Hubble Space Telescope was placed into a safe hold at approximately 8:30 a.m. EST Saturday morning when gyroscope #1 ceased operation. With only two operational gyros remaining, the science program will be suspended until completion of Servicing Mission 3A, currently scheduled for launch aboard Space Shuttle Discovery on Dec. 6, 1999.

NASA's Hubble Space Telescope was placed into a safe hold at approximately 8:30 a.m. EST Saturday morning when gyroscope #1 ceased operation. With only two operational gyros remaining, the science program will be suspended until completion of Servicing Mission 3A, currently scheduled for launch aboard Space Shuttle Discovery on Dec. 6, 1999.

This gyro situation is not expected to impact the upcoming servicing mission. In fact, anticipation that another gyro could fail was the primary reason that Hubble managers scheduled an early repair mission and split the third servicing mission activities into two flights: Servicing Mission-3A (Dec. 6, 1999) and Servicing Mission-3B (Mid-2001).

"This event underscores the wisdom of dividing the third HST Servicing Mission into two parts, with Servicing Mission 3A scheduled for December 1999 -- only 3 weeks of science data will be lost," said Dr. John Campbell, Hubble Space Telescope Program Manager at NASA's Goddard Space Flight Center, Greenbelt, MD.

The safe-hold mode has been thoroughly tested and used twice since Hubble's launch in 1990. The telescope is not at risk. This protective safe mode allows ground control of the telescope, but with only two gyros working, Hubble cannot be aimed with the precision necessary for scientific observations of the sky.

The safe mode does not require gyros, so even if another gyro should fail in the next few weeks, HST will remain safe, according to project managers. The aperture door has been closed to protect the optics, and the spacecraft is aligned to the sun to ensure adequate power is received by Hubble's solar panels.

Engineers are investigating the cause of the gyro loss. The gyro will be returned to ground after the upcoming servicing mission for in-depth analysis.

During Servicing Mission 3A, astronauts will replace all the gyroscopes, a fine guidance sensor, a transmitter, a spare solid-state recorder and a high-voltage/temperature kit for protecting batteries from overheating. Additionally, the crew will install an advanced computer.

Servicing Mission 3B will be conducted in 2001 to complete the third HST servicing mission activities.

Additional information on the mission and Hubble is available at:

http://hubble.gsfc.nasa.gov/


Story Source:

The above story is based on materials provided by National Aeronautics And Space Administration. Note: Materials may be edited for content and length.


Cite This Page:

National Aeronautics And Space Administration. "Hubble Telescope Placed Into Safe Hold As Gyroscope Fails." ScienceDaily. ScienceDaily, 16 November 1999. <www.sciencedaily.com/releases/1999/11/991116060954.htm>.
National Aeronautics And Space Administration. (1999, November 16). Hubble Telescope Placed Into Safe Hold As Gyroscope Fails. ScienceDaily. Retrieved August 30, 2014 from www.sciencedaily.com/releases/1999/11/991116060954.htm
National Aeronautics And Space Administration. "Hubble Telescope Placed Into Safe Hold As Gyroscope Fails." ScienceDaily. www.sciencedaily.com/releases/1999/11/991116060954.htm (accessed August 30, 2014).

Share This




More Space & Time News

Saturday, August 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Experiment Tests Whether Universe Is Actually A Hologram

Experiment Tests Whether Universe Is Actually A Hologram

Newsy (Aug. 27, 2014) Researchers at Fermilab are using a device called "The Holometer" to test whether our universe is actually a 2-D hologram that just seems 3-D. Video provided by Newsy
Powered by NewsLook.com
SpaceX’s Falcon 9 Rocket Explodes After Liftoff

SpaceX’s Falcon 9 Rocket Explodes After Liftoff

Newsy (Aug. 23, 2014) The private spaceflight company says it is preparing a thorough investigation into Friday's mishap. Video provided by Newsy
Powered by NewsLook.com
Did Russia Really Find Plankton On The ISS? NASA Not So Sure

Did Russia Really Find Plankton On The ISS? NASA Not So Sure

Newsy (Aug. 21, 2014) Russian cosmonauts say they've found evidence of sea plankton on the International Space Station's windows. NASA is a little more skeptical. Video provided by Newsy
Powered by NewsLook.com
Space to Ground: Hello Georges

Space to Ground: Hello Georges

NASA (Aug. 18, 2014) Europe's ATV-5 delivers new science and the crew tests smart SPHERES. Questions or comments? Use #spacetoground to talk to us. Video provided by NASA
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins