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2021-07-17 Science & Technology

NASA revives ailing Hubble Space Telescope with switch to backup computer

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Posted by Snomoth Whereling9836 2021-07-17 01:32|| || Front Page|| [9 views ] Top

#1 Took a call to someone still alive but who remembered back when they engineered it that there was a backup switch in the original design?

Posted by Procopius2k 2021-07-17 07:15|| 2021-07-17 07:15|| Front Page Top

#2 Hubble Space Telescope Facts
NASA named the world's first space-based optical telescope after American astronomer Edwin P. Hubble (1889 -- 1953). Dr. Hubble confirmed an "expanding" universe, which provided the foundation for the big-bang theory.

Mission
Launch: April 24, 1990, from space shuttle Discovery (STS-31)
Deployment: April 25, 1990
First Image: May 20, 1990: Star cluster NGC 3532
Servicing Mission 1 (STS-61): December 1993
Servicing Mission 2 (STS-82): February 1997
Servicing Mission 3A (STS-103): December 1999
Servicing Mission 3B (STS-109): February 2002
Servicing Mission 4 (STS-125): May 2009
Size
Length: 43.5 feet (13.2 m)
Weight: At Launch: about 24,000 pounds (10,886 kg)
Post SM4: about 27,000 pounds (12,247 kg)
Maximum Diameter: 14 feet (4.2 m)
Spaceflight Statistics
Low Earth Orbit: Altitude of 340 miles (295 nautical miles, or 547 km), inclined 28.5 degrees to the equator
Time to Complete One Orbit: about 95 minutes
Speed: about 17,000 mph (27,300 kph)
Optical Capabilities
Sensitivity to Light: Ultraviolet through Infrared (115–2500 nanometers)
Hubble's Mirrors
Primary Mirror Diameter: 94.5 inches (2.4 m)
Primary Mirror Weight: 1,825 pounds (828 kg)
Secondary Mirror Diameter: 12 inches (0.3 m)
Secondary Mirror Weight: 27.4 pounds (12.3 kg)
Pointing Accuracy
In order to take images of distant, faint objects, Hubble must be extremely steady and accurate. The telescope is able to lock onto a target without deviating more than 7/1000th of an arcsecond, or about the width of a human hair seen at a distance of 1 mile.
Data Statistics
Hubble transmits about 150 gigabits of raw science data every week.
Power Needs
Energy Source: The Sun
Mechanism: Two 25-foot solar panels
Power Generation (in Sunlight): about 5,500 watts
Power Usage (Average): about 2,100 watts
Power Storage
Batteries: 6 nickel-hydrogen (NiH)
Storage Capacity: Equal to about 22 average car batteries
Did you know...
Hubble has made more than 1.3 million observations since its mission began in 1990.
Astronomers using Hubble data have published more than 15,000 scientific papers, making it one of the most productive scientific instruments ever built. Those papers have been cited in other papers 738,000 times.
Hubble does not travel to stars, planets or galaxies. It takes pictures of them as it whirls around Earth at about 17,000 mph.
Hubble has circled Earth and gone more than 4 billion miles along a circular low earth orbit currently about 340 miles in altitude.
Hubble has no thrusters. To change angles, it uses Newton’s third law by spinning its wheels in the opposite direction. It turns at about the speed of a minute hand on a clock, taking 15 minutes to turn 90 degrees.
Hubble has the pointing accuracy of .007 arcseconds, which is like being able to shine a laser beam on President Roosevelt’s head on a dime about 200 miles away.
Outside the haze of our atmosphere, it can see astronomical objects with an angular size of 0.05 arcseconds, which is like seeing a pair of fireflies in Tokyo that are less than 10 feet apart from Washington, DC.
Due to the combination of optics and sensitive detectors and with no atmosphere to interfere with the light reaching it, Hubble can spot a night light on the surface of the Moon from Earth.
Hubble has peered back into the very distant past, to locations more than 13.4 billion light-years from Earth.
Hubble generates about 10 terabytes of new data per year. The total archive is currently over 150 TB in size.
Hubble weighed about 24,000 pounds at launch but if returned to Earth today would weigh about 27,000 pounds — on the order of two full-grown African elephants.
Hubble's primary mirror is 2.4 meters (7 feet, 10.5 inches) across. It was so finely polished that if you scaled it to be the diameter of the Earth, you would not find a bump more than 6 inches tall.
Hubble is 13.3 meters (43.5 feet) long — the length of a large school bus.

Posted by Crineling de Medici8721 2021-07-17 08:21|| 2021-07-17 08:21|| Front Page Top

#3 Took a call to someone still alive but who remembered back when they engineered it that there was a backup switch in the original design?

Clint Eastwood, Donald Sutherland, Tommy Lee Jones and Jim Garner to the white courtesy phone for an important call..

Posted by Warthog 2021-07-17 09:36|| 2021-07-17 09:36|| Front Page Top

#4 up up down down left right left right b a select start

Posted by swksvolFF 2021-07-17 10:12|| 2021-07-17 10:12|| Front Page Top

#5 Took a call to someone still alive but who remembered back when they engineered it that there was a backup switch in the original design?

From what I saw, they have four redundant computers on board. Primary failed -- they tried the secondary and it failed. They just now decided to try the tertiary. It likely took so long because the primary and secondary appear to have failed the same way -- and that would be confusing, as the odds of that have to be slim.

Posted by Rob Crawford 2021-07-17 11:47|| 2021-07-17 11:47|| Front Page Top

#6 up up down down left right left right b a select start

Snark of the Day! (assuming you can read the code)

Posted by SteveS 2021-07-17 15:09|| 2021-07-17 15:09|| Front Page Top

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