ad info




CNN.com
 MAIN PAGE
 WORLD
 U.S.
 LOCAL
 POLITICS
 WEATHER
 BUSINESS
 SPORTS
 TECHNOLOGY
* SPACE
 HEALTH
 ENTERTAINMENT
 BOOKS
 TRAVEL
 FOOD
 ARTS & STYLE
 NATURE
 IN-DEPTH
 ANALYSIS
 myCNN

 Headline News brief
 news quiz
 daily almanac

  MULTIMEDIA:
 video
 video archive
 audio
 multimedia showcase
 more services

  E-MAIL:
Subscribe to one of our news e-mail lists.
Enter your address:
Or:
Get a free e-mail account

 DISCUSSION:
 message boards
 chat
 feedback

  CNN WEB SITES:
CNN Websites
 AsiaNow
 En Español
 Em Português
 Svenska
 Norge
 Danmark
 Italian

 FASTER ACCESS:
 europe
 japan

 TIME INC. SITES:
 CNN NETWORKS:
Networks image
 more networks
 transcripts

 SITE INFO:
 help
 contents
 search
 ad info
 jobs

 WEB SERVICES:

  sci-tech > space > story pagecorner  
Downlinks with Miles O'Brien

Shuttle Discovery launch delayed again

shuttle
 

October 7, 1999
Web posted at: 5:16 p.m. EDT (1625 GMT)

By Miles O'Brien
CNN Correspondent

ATLANTA (CNN) - The NASA launch cabal engaged in a multi-variable, multi-layered discussion on Thursday - hoping to achieve some sort of manifest destiny for their fleet of shuttles.

And while they have succeeded in adding some clarity to their future - they have greatly complicated our space coverage plans.

Lest I bury the lead, during a 3-hour "telecon," launch managers in Houston and at the Cape decided to set a launch date for the third Hubble repair mission. Discovery is scheduled to leave Launch Pad 39-B at 4:32 a.m. EDT, on December 2.

  INTERACTIVE
  3-D VRML models:
  Maneuver the Hubble Space Telescope
 
  MESSAGE BOARDS
Star gazing

Space shuttle
 

The next day, December 3, The Mars Polar Lander should arrive on the surface of the Red Planet. The first images should be back on earth a few days later.

You see the problem? Two big space stories ongoing simultaneously. It will be an interesting week.

The wiring inspections and repairs are all but complete on Discovery. There are enough splices, (large and small) to necessitate a "full-up" test of Discovery's electrical system. You wouldn't want to find out about a loose connection or a crossed wire on ascent -- or in low earth orbit. Everything electrical will have to be spooled up and checked out. This will take some time -- but not so much time that it would cause an additional delay.

wires
The faulty wiring that led to the lengthy inspections  

Meanwhile, there is the problem with the valve in Discovery's Orbital Maneuvering System (OMS) pod. There are two OMS engines on every shuttle. Their nozzles sit above the orbiters three main engines -- protruding from the humps on either side of the tail. Among other things, OMS engines help shuttles reach, circularize and ultimately leave earth orbit.

Each OMS engine can produce 6,000 pounds of thrust, working the same way as their smaller siblings -- the network of maneuvering rockets called the Reaction Control System. Both are hypergolic systems - meaning their fuel and oxidizer spontaneously ignite on contact (no spark plugs required).

So when technicians discovered a leak in one of the valves designed to control the flow of the oxidizer (nitrogen tetroxide) into the thrust chamber at the top of the nozzle, they realized they had a potentially big problem. After using an electronic sniffer to make sure the leak was isolated in one place, they cannibalized a valve from sister ship Columbia.

hubble
Hubble Space Telescope  

They will be watching the replaced valve closely for 72 hours after it is installed. If it leaks again, they may have to replace the entire OMS pod (also cannibalized from Columbia). Even if that happens, launch managers feel they have enough time to install the OMS pod before Discovery rolls out of the Vehicle Assembly Building at the end of October.

All of this will be finalized at a Launch Readiness Review on November 10. So, assuming things go as planned, during the week of December 6, space fans will receive a holiday treat from NASA: a dramatic series of four spacewalks during East Coast overnight hours - followed during the day by some equally dramatic images from the surface of another world.

As for Endeavour and her mission to create a radar map of the earth: with wiring inspections 90 percent complete on the orbiter NASA lovingly calls OV-105, she is scheduled to launch on January 13.

Atlantis will fly her mission to the International Space Station no earlier than February 10. Wiring inspections -- and work on a leaking ammonia boiler -- lie ahead. So pencil that one in. Matter of fact, I would stick with pencils in general when trying to keep track of all this.



RELATED STORIES:
Downlinks Archive

Hubble snaps clues about origin of spiral galaxies
October 6, 1999
Stellar nursery in nearby galaxy teems with activity
September 29, 1999
Galaxies dance before merger
September 6, 1999
Hubble captures celestial 'hourglass'
August 25, 1999
Hubble sees stars in red, white and blue
July 6, 1999
Hubble snaps Martian close-ups
July 1, 1999
Hubble catches cosmic 'butterfly'
June 14, 1999
Hubble picture reveals seeds of planet-making
June 2, 1999

RELATED SITES:
NASA Homepage
Hubble Heritage Project
Space Telescope Science Institute
The Next Generation Space
Note: Pages will open in a new browser window
External sites are not endorsed by CNN Interactive.
 LATEST HEADLINES:
SEARCH CNN.com
Enter keyword(s)   go    help

Back to the top   © 2001 Cable News Network. All Rights Reserved.
Terms under which this service is provided to you.
Read our privacy guidelines.