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Hubble Maps 3-D Structure of Ejected Material Around Erupting Star
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By NASA
“Trying to do stellar observations from Earth is like trying to do birdwatching from the bottom of a lake.” James B. Odom, Hubble Program Manager 1983-1990.
The third servicing mission to the Hubble Space Telescope, placed in orbit in 1990, occurred during the STS-103 mission in December 1999. During the mission, originally planned for June 2000 but accelerated by six months following unexpected failures of the telescope’s attitude control gyroscopes, the astronauts restored the facility to full functionality. During their eight-day mission that featured the first space shuttle crew to spend Christmas in space, the seven-member U.S. and European crew rendezvoused with and captured Hubble, and four astronauts in rotating teams of two conducted three lengthy and complex spacewalks to service and upgrade the telescope. They redeployed the telescope with greater capabilities than ever before to continue its mission to help scientists unlock the secrets of the universe.
Schematic showing the Hubble Space Telescope’s major components. Workers inspect the Hubble Space Telescope’s 94-inch diameter primary mirror prior to assembly. Astronauts release the Hubble Space Telescope in April 1990 during the STS-31 mission. The discovery after the Hubble Space Telescope’s launch in 1990 that its primary mirror suffered from a flaw called spherical aberration disappointed scientists who could not obtain the sharp images they had expected. But thanks to the Hubble’s built-in feature of on-orbit servicing, NASA devised a plan to correct the telescope’s optics during the first planned repair mission in 1993. A second servicing mission in 1997 upgraded the telescope’s capabilities until the next mission planned for three years later. But after three of the telescope’s six gyroscopes failed in 1997, 1998, and 1999, mission rules dictated a call up mission in case additional gyroscope failures sent Hubble into a safe mode. NASA elected to move up some of the servicing tasks from the third mission, splitting it into missions 3A and 3B, planning to fly 3A in October 1999 on Discovery’s STS-103 mission primarily to replace the failed gyroscopes. Delays to the shuttle fleet resulting from anomalies during the launch of STS-93 in July 1993 slipped STS-103 first into November and ultimately into December. Technical issues with Discovery itself pushed the launch date to mid-December, and raised concerns about having a shuttle in orbit during the Y2K transition. Once the launch had slipped to Dec. 19, mission planners cut the mission from 10 to eight days, deleting one of the four spacewalks, to ensure a return before the end of the calendar year. The servicing mission couldn’t come soon enough, as a fourth gyroscope failed aboard Hubble in mid-November, with Discovery already poised on the launch pad to prepare for STS-103. Controllers placed Hubble in a safe mode until the astronauts arrived.
The STS-103 crew of C. Michael Foale, left, Claude Nicollier, Scott J. Kelly, Curtis L. Brown, Jean-François A. Clervoy, John M. Grunsfeld, and Steven L. Smith. The STS-103 crew patch. The mission patch for the Hubble Servicing Mission-3A. To execute the third Hubble Servicing Mission, in July 1998 NASA selected an experienced four-person team to carry out a record-breaking six spacewalks on the flight then planned for June 2000. The spacewalkers included Mission Specialists Steven L. Smith serving as payload commander, John M. Grunsfeld, C. Michael Foale, and European Space Agency (ESA) astronaut Claude Nicollier from Switzerland. The addition in March 1999 of Commander Curtis L. Brown, Pilot Scott J. Kelly, and Mission Specialist ESA astronaut Jean-François A. Clervoy of France rounded out the highly experienced crew with 18 previous spaceflights among them. Brown earned the distinction as only the fifth person to fly in space six times. For Kelly, STS-103 marked his first spaceflight. Smith, Clervoy, and Grunsfeld each had flown two previous missions, Foale four including a long-duration mission aboard Mir, and Nicollier three. Smith participated in three spacewalks during the second Hubble Servicing Mission and Nicollier served as the Remote Manipulator System (RMS) or robotic arm operator during the first.
The STS-103 crew at the traditional prelaunch breakfast at NASA’s Kennedy Space Center in Florida. Suited up, the STS-103 astronauts leave crew quarters for the trip to Launch Pad 39B. Space shuttle Discovery on Launch Pad 39B, awaiting launch. Discovery arrived back to KSC at the end of the STS-96 mission on June 6, 1999, and workers towed it to the Orbiter Processing Facility the same day to begin readying it for STS-103. The vehicle rolled over to the Vehicle Assembly Building on Nov. 4, where workers mated it with its external tank and twin solid rocket boosters, before rolling the stack out to Launch Pad 39B on Nov. 13.
Liftoff of space shuttle Discovery on the STS-103 Hubble Space Telescope servicing mission 3A. The Hubble Space Telescope as Discovery approaches. The STS-103 crew berthing the Hubble into the payload bay. Beginning its 27th trip into space, Discovery lifted off from Launch Pad 39B at 7:50 p.m. EST on Dec. 19 to fix the ailing space telescope. Two days later, Brown and Kelly maneuvered Discovery to within range of Hubble so Clervoy operating the 50-foot-long RMS could grapple the telescope and berth it into the payload bay.
During the first spacewalk, astronauts John M. Grunsfeld, left, and Steven L. Smith replacing one of the Rate Sensor Units containing two gyroscopes. Smith gives a thumbs up with his image reflected in the Hubble Space Telescope. Smith and Grunsfeld conducted the mission’s first spacewalk on Dec. 22, the flight’s fourth day in space. The duo, aided by Clervoy operating the RMS from inside Discovery, completed two of mission’s highest priority objectives. They replaced the failed gyroscopes, installing three new Rate Sensor Units, each containing two gyroscopes, to return control to the ailing telescope. They also installed six Voltage/Temperature Improvement Kits to prevent the telescope’s batteries from overheating as they aged. The excursion lasted eight hours 15 minutes, at the time the second longest spacewalk.
During the second spacewalk, astronauts C. Michael Foale, left, and Claude Nicollier during the changeout of the fine guidance sensor. Foale at the end of the Remote Manipulator System services the Hubble Space Telescope. The next day, Nicollier and Foale conducted the mission’s second spacewalk. The main task for this excursion involved installing a new computer aboard Hubble, replacing the original 1970s vintage unit. The new radiation-hardened system ran 20 times faster and carried six times more memory while using one-third the electrical power. They also installed a fine guidance sensor before concluding the eight-hour 10-minute spacewalk.
Astronauts Steven L. Smith, left, and John M. Grunsfeld begin their servicing activities during the third spacewalk. At the end of the third and final spacewalk, Grunsfeld, left, and Smith provide closing comments about the work the mission accomplished to service the Hubble Space Telescope. Smith and Grunsfeld ventured outside for a second time to complete the flight’s third and final spacewalk on Dec. 24, the first spacewalk conducted on Christmas Eve day. First, they replaced an old reel-to-reel tape recorder with a solid state unit providing a 10-fold increase in recording capability and replaced a failed data transmitter. They installed seven new covers on Hubble’s electronics bay doors for added protection of the telescope’s insulation. This third spacewalk lasted eight hours eight minutes.
The first space shuttle crew to celebrate Christmas in space, the STS-103 astronauts pose wearing Santa hats. The Hubble Space Telescope shortly after the STS-103 crew released it. The next day, the STS-103 astronauts earned the distinction as the first space shuttle crew to spend Christmas Day in space. Clervoy grappled Hubble, lifted it out of the payload bay and released it to continue its mission. Hubble Space Telescope Program Manager John H. Campbell said after the release, “The spacecraft is being guided by its new gyros under the control of its brand new computer. [It] is now orbiting freely and is in fantastic shape.” After deploying Hubble, the astronauts enjoyed a well-deserved Christmas dinner, with Clervoy providing French delicacies. The crew spent Dec. 26 readying Discovery for its return to Earth, including testing its reaction control system thrusters and aerodynamic surfaces and stowing unneeded gear.
Astronauts Steven L. Smith, left, Claude Nicollier, and John M. Grunsfeld complete their fluid loading protocol and put on their launch and entry suits prior to reentry. Space shuttle Discovery makes a perfect night landing at NASA’s Kennedy Space Center in Florida. The crew welcome home ceremony at Ellington Field in Houston. On Dec. 27, the astronauts donned their launch and entry suits and prepared for the return to Earth. They closed the payload bay doors and fired Discovery’s engines to bring them out of orbit. Just before landing, Kelly lowered the craft’s landing gear and Brown guided Discovery to a smooth night landing at KSC, concluding a flight of seven days, 23 hours, 11 minutes. They circled the Earth 119 times. The flight marked Discovery’s last solo flight as all its subsequent missions docked with the International Space Station. Workers at KSC began readying it for its next mission, STS-92 in October 2000.
The Hubble Space Telescope continues to operate today, far exceeding the five-year life extension expected from the last of the servicing missions in 2009. Joined in space by the James Webb Space Telescope in 2021, the two instruments together continue to image the skies across a broad range of the electromagnetic spectrum to provide scientists with the tools to gain unprecedented insights into the universe and its formation.
Watch the STS-103 crew narrate a video of their Hubble servicing mission.
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By NASA
Hubble Space Telescope Hubble Home Overview About Hubble The History of Hubble Hubble Timeline Why Have a Telescope in Space? Hubble by the Numbers At the Museum FAQs Impact & Benefits Hubble’s Impact & Benefits Science Impacts Cultural Impact Technology Benefits Impact on Human Spaceflight Astro Community Impacts Science Hubble Science Science Themes Science Highlights Science Behind Discoveries Hubble’s Partners in Science Universe Uncovered Explore the Night Sky Observatory Hubble Observatory Hubble Design Mission Operations Missions to Hubble Hubble vs Webb Team Hubble Team Career Aspirations Hubble Astronauts News Hubble News Hubble News Archive Social Media Media Resources Multimedia Multimedia Images Videos Sonifications Podcasts E-books Online Activities Lithographs Fact Sheets Glossary Posters Hubble on the NASA App More 35th Anniversary 2 min read
Hubble Spies a Cosmic Eye
This NASA/ESA Hubble Space Telescope image features the spiral galaxy NGC 2566. ESA/Hubble & NASA, D. Thilker This NASA/ESA Hubble Space Telescope image features the spiral galaxy NGC 2566, which sits 76 million light-years away in the constellation Puppis. A prominent bar of stars stretches across the center of this galaxy, and spiral arms emerge from each end of the bar. Because NGC 2566 appears tilted from our perspective, its disk takes on an almond shape, giving the galaxy the appearance of a cosmic eye.
As NGC 2566 appears to gaze at us, astronomers gaze right back, using Hubble to survey the galaxy’s star clusters and star-forming regions. The Hubble data are especially valuable for studying stars that are just a few million years old; these stars are bright at the ultraviolet and visible wavelengths to which Hubble is sensitive. Using these data, researchers can measure the ages of NGC 2566’s stars, which helps piece together the timeline of the galaxy’s star formation and the exchange of gas between star-forming clouds and the stars themselves.
Hubble regularly teams up with other astronomical observatories to examine objects like NGC 2566, including the NASA/ESA/CSA James Webb Space Telescope. Webb data complements Hubble’s by going beyond the infrared wavelengths of light Hubble can see, better defining areas of warm, glowing dust. At even longer wavelengths, the Atacama Large Millimeter/submillimeter Array (ALMA) of 66 radio telescopes that work together can capture detailed images of the clouds of gas and dust in which stars form. Together, Hubble, Webb, and ALMA provide an overview of the formation, lives, and deaths of stars in galaxies across the universe.
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How does Hubble work with other telescopes?
Hubble’s Galaxies
Galaxy Details and Mergers
Hubble Focus E-Book: Galaxies through Space and Time
Facebook logo @NASAHubble @NASAHubble Instagram logo @NASAHubble Media Contact:
Claire Andreoli (claire.andreoli@nasa.gov)
NASA’s Goddard Space Flight Center, Greenbelt, MD
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Last Updated Dec 19, 2024 Editor Andrea Gianopoulos Location NASA Goddard Space Flight Center Related Terms
Astrophysics Astrophysics Division Galaxies Goddard Space Flight Center Hubble Space Telescope Spiral Galaxies Keep Exploring Discover More Topics From NASA
Hubble Space Telescope
Since its 1990 launch, the Hubble Space Telescope has changed our fundamental understanding of the universe.
Hubble’s Partners in Science
Hubble’s Night Sky Challenge
Hubble’s Galaxies
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By European Space Agency
Image: With the festive season approaching, even Earth-observing satellites are getting into the spirit, capturing a stunning compilation of European cities that resemble stars. View the full article
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By NASA
Hubble Space Telescope Hubble Home Overview About Hubble The History of Hubble Hubble Timeline Why Have a Telescope in Space? Hubble by the Numbers At the Museum FAQs Impact & Benefits Hubble’s Impact & Benefits Science Impacts Cultural Impact Technology Benefits Impact on Human Spaceflight Astro Community Impacts Science Hubble Science Science Themes Science Highlights Science Behind Discoveries Hubble’s Partners in Science Universe Uncovered Explore the Night Sky Observatory Hubble Observatory Hubble Design Mission Operations Missions to Hubble Hubble vs Webb Team Hubble Team Career Aspirations Hubble Astronauts News Hubble News Hubble News Archive Social Media Media Resources Multimedia Multimedia Images Videos Sonifications Podcasts E-books Online Activities Lithographs Fact Sheets Glossary Posters Hubble on the NASA App More 35th Anniversary 2 min read
Hubble Images a Grand Spiral
This NASA/ESA Hubble Space Telescope image features the spiral galaxy NGC 5643. ESA/Hubble & NASA, A. Riess, D. Thilker, D. De Martin (ESA/Hubble), M. Zamani (ESA/Hubble) This NASA/ESA Hubble Space Telescope image features the glorious spiral galaxy NGC 5643, which is located roughly 40 million light-years away in the constellation Lupus, the Wolf. NGC 5643 is a grand design spiral, which refers to the galaxy’s symmetrical form with two large, winding spiral arms that are clearly visible. Bright-blue stars define the galaxy’s spiral arms, along with lacy reddish-brown dust clouds and pink star-forming regions.
As fascinating as the galaxy appears at visible wavelengths, some of NGC 5643’s most interesting features are invisible to the human eye. Ultraviolet and X-ray images and spectra of NGC 5643 show that the galaxy hosts an active galactic nucleus: an especially bright galactic core powered by a feasting supermassive black hole. When a supermassive black hole ensnares gas from its surroundings, the gas collects in a disk that heats up to hundreds of thousands of degrees. The superheated gas shines brightly across the electromagnetic spectrum, but especially at X-ray wavelengths.
NGC 5643’s active galactic nucleus isn’t the brightest source of X-rays in the galaxy, though. Researchers using ESA’s XMM-Newton discovered an even brighter X-ray-emitting object, called NGC 5643 X-1, on the galaxy’s outskirts. What could be a more powerful source of X-rays than a supermassive black hole? Surprisingly, the answer appears to be a much smaller black hole! While the exact identity of NGC 5643 X-1 is unknown, evidence points to a black hole that is about 30 times more massive than the Sun. Locked in an orbital dance with a companion star, the black hole ensnares gas from its stellar companion, creating a superheated disk that outshines the NGC 5643’s galactic core.
NGC 5643 was also the subject of a previous Hubble image. The new image incorporates additional wavelengths of light, including the red color that is characteristic of gas heated by massive young stars.
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Hubble’s Galaxies
Science Behind the Discoveries: Black Holes
Hubble’s Black Holes
Hubble Focus E-Book: Galaxies through Space and Time
Facebook logo @NASAHubble @NASAHubble Instagram logo @NASAHubble Media Contact:
Claire Andreoli (claire.andreoli@nasa.gov)
NASA’s Goddard Space Flight Center, Greenbelt, MD
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Last Updated Dec 12, 2024 Editor Andrea Gianopoulos Location NASA Goddard Space Flight Center Related Terms
Astrophysics Astrophysics Division Galaxies Goddard Space Flight Center Hubble Space Telescope Spiral Galaxies Keep Exploring Discover More Topics From Hubble
Hubble Space Telescope
Since its 1990 launch, the Hubble Space Telescope has changed our fundamental understanding of the universe.
Hubble’s Night Sky Challenge
Hubble Posters
Hubble by the Numbers
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By NASA
This article is from the 2024 Technical Update.
The NESC evaluated material compatibility of some common aerospace metals in monomethylhydrazine (MMH) and nitrogen tetroxide (MON-3). Previous work had identified a lack of quantitative compatibility data for nickel alloy 718, 300 series stainless steel, and titanium Ti-6Al-4V in MMH and MON-3 to support the use of zero-failure-tolerant, thin-walled pressure barriers in these propellants. Static (i.e., not flowing) general corrosion and electrochemistry testing was conducted, evaluating varied processing forms and heat treatment of the metals, water content of propellant, and exposure duration. Corrosion-rate data for all tested product forms, fluids, and durations were on the order of 1 x 10–6 inch per year rather than the previously documented “less than 1 x 10–3 inch per year”. The majority of the corrosion products were seen in the first 20 days of exposure, with an overall corrosion rate decreasing with time due to the increased divisor (time). It is therefore recommended that corrosion testing be performed at multiple short-term durations to inform the need for longer-duration testing.
Background
Nickel alloy 718, 300 series stainless steel, and Ti-6Al-4V are commonly used in storable propulsion systems (i.e., MMH/MON-3), but a concern was raised regarding what quantitative compatibility data were available for proposed zero-failure-tolerant, thin-walled (~0.005 to 0.010 inch thickness) pressure barrier designs. A literature search found that limited and conflicting data were available for commonly used aerospace metals in MMH and MON-3. For example, corrosion behavior was listed qualitatively (e.g., “A” rating), data on materials and fluids tested were imprecise, fluids were identified as contaminated without describing how they were contaminated, no compatibility data were found on relevant geometry specimens (i.e., very thin-walled or convoluted), and limited data were available to quantify differences between tested materials and flight components. When corrosion data were quantified, documented sensitivity was “1 x 10–3 inch per year or less”, which is insufficient for assessing long-duration, thin-walled, flight-weight applications.
Discussion
General corrosion testing was performed with a static/non-flowing configuration based on NASA-STD-6001, Test 15 [1]. Design of experiments methods were used to develop a test matrix varying material, propellant, propellant water content, and tested duration. Materials tested were nickel alloy 718 (solution annealed sheet, aged sheet, aged/welded sheet, and hydroformed bellows), 300 series stainless steel (low carbon sheet, titanium stabilized sheet, and hydroformed bellows), and Ti 6Al-4V sheet. Samples were tested in sealed test tubes in MMH and MON-3 with water content ranging from as-received (“dry”) up to specification allowable limits [2,3]. Tested durations ranged from 20 to 365 days. Measurements included inductively coupled plasma mass spectrometry (ICPMS) to identify corrosion products and their concentrations in test fluid, gravimetric (i.e., scale) measurements pre- and post-exposure, and visual inspection. Bimetallic pairs (titanium stabilized 300 series stainless steel: Ti 6Al-4V and nickel alloy 718: Ti 6Al-4V) were tested for up to 65 days in both MMH and MON-3. The test setup incorporated important features of the test standard (e.g., electrode spacing and finish) and adapted the configuration for MMH/MON-3 operation. Measurements included potential difference and current flow between samples. Figure 1 shows images of the general corrosion and bimetallic pair test setups.
Test Results
For all tested materials and product forms, corrosion rates were on the order of 1 x 10–6 inch per year in MMH or MON-3, three orders of magnitude lower than historically reported. Corrosion products were generated in the first 20 days of exposure, and corrosion rate decreased with time due to the increase in divisor (i.e., time). Corrosion products increased as the water content of the propellants increased but remained in the same order of magnitude between the as-received dry propellant and propellant containing the maximum water content allowed by specification. Figure 2 illustrates test results for corrosion rate, mass loss with duration, and mass loss with water content. It is important to note that water has been demonstrated to contribute to flow decay even when water is within the specification allowable limit, and previous NASA-STD-6001 Test 15 data have demonstrated susceptibility of some nickel alloys to crevice-type corrosion attack [4]. Therefore, these results do not reduce the importance of considering the system impact of water content and evaluating for crevice corrosion behavior. Finally, in the bimetallic pair testing, tested materials did not measurably corrode in MON-3 and MMH within specification-allowable water content, as evidenced by no visual indications of corrosion and very low electrical interaction (i.e., corrosion rates derived to be less than 1 microinch per year from electrical interaction).
Recommendations
It is recommended that corrosion testing be performed at multiple shortterm durations to inform the need for longer-duration testing.
References
NASA-STD-6001 Flammability, Odor, Offgassing, and Compatibility Requirements
and Test Procedures for Materials In Environments that Support Combustion MIL-PRF-27404 Performance Specification: Propellant, Monomethylhydrazine MIL-PRF-26539 Performance Specification: Propellants, Dinitrogen Tetroxide WSTF Test 15 Report 12-45708 and WSTF Test 15 Report 13-46207 View the full article
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