posted 07-23-2009 05:27 PM               

NASA Celebrates Chandra X-Ray Observatory's 10th Anniversary

Ten years ago, on July 23, 1999, NASA's Chandra X-ray Observatory was launched aboard the space shuttle Columbia and deployed into orbit. Chandra has doubled its original five-year mission, ushering in an unprecedented decade of discovery for the high-energy universe.

With its unrivaled ability to create high-resolution X- ray images, Chandra has enabled astronomers to investigate phenomena as diverse as comets, black holes, dark matter and dark energy.

"Chandra's discoveries are truly astonishing and have made dramatic changes to our understanding of the universe and its constituents," said Martin Weisskopf, Chandra project scientist at NASA's Marshall Space Flight Center in Huntsville, Ala.

The science that has been generated by Chandra -- both on its own and in conjunction with other telescopes in space and on the ground -- has had a widespread, transformative impact on 21st century astrophysics. Chandra has provided the strongest evidence yet that dark matter must exist. It has independently confirmed the existence of dark energy and made spectacular images of titanic explosions produced by matter swirling toward supermassive black holes.

To commemorate the 10th anniversary of Chandra, three new versions of classic Chandra images will be released during the next three months. These images, the first of which is available Thursday, provide new data and a more complete view of objects that Chandra observed in earlier stages of its mission. The image being released today is of E0102-72, the spectacular remains of an exploded star.

"The Great Observatories program -- of which Chandra is a major part -- shows how astronomers need as many tools as possible to tackle the big questions out there," said Ed Weiler, associate administrator of NASA's Science Mission Directorate at NASA Headquarters in Washington. NASA's other "Great Observatories" are the Hubble Space Telescope, Compton Gamma-Ray Observatory and Spitzer Space Telescope.

The next image will be released in August to highlight the anniversary of when Chandra opened up for the first time and gathered light on its detectors. The third image will be released during "Chandra's First Decade of Discovery" symposium in Boston, which begins Sept. 22.

"I am extremely proud of the tremendous team of people who worked so hard to make Chandra a success," said Harvey Tananbaum, director of the Chandra X-ray Center at the Smithsonian Astrophysical Observatory in Cambridge, Mass. "It has taken partners at NASA, industry and academia to make Chandra the crown jewel of high-energy astrophysics."

Tananbaum and Nobel Prize winner Riccardo Giacconi originally proposed Chandra to NASA in 1976. Unlike the Hubble Space Telescope, Chandra is in a highly elliptical orbit that takes it almost one third of the way to the moon, and was not designed to be serviced after it was deployed.

Marshall manages the Chandra program for NASA's Science Mission Directorate. The Smithsonian Astrophysical Observatory controls science and flight operations from the Chandra X-ray Center.

posted 11-16-2010 08:30 AM               

NASA's Chandra Finds Youngest Nearby Black Hole

Astronomers using NASA's Chandra X-ray Observatory have found evidence of the youngest black hole known to exist in our cosmic neighborhood. The 30-year-old black hole provides a unique opportunity to watch this type of object develop from infancy.

The black hole could help scientists better understand how massive stars explode, which ones leave behind black holes or neutron stars, and the number of black holes in our galaxy and others.

The 30-year-old object is a remnant of SN 1979C, a supernova in the galaxy M100 approximately 50 million light years from Earth. Data from Chandra, NASA's Swift satellite, the European Space Agency's XMM-Newton and the German ROSAT observatory revealed a bright source of X-rays that has remained steady during observation from 1995 to 2007. This suggests the object is a black hole being fed either by material falling into it from the supernova or a binary companion.

"If our interpretation is correct, this is the nearest example where the birth of a black hole has been observed," said Daniel Patnaude of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. who led the study.

The scientists think SN 1979C, first discovered by an amateur astronomer in 1979, formed when a star about 20 times more massive than the sun collapsed. Many new black holes in the distant universe previously have been detected in the form of gamma-ray bursts (GRBs).

However, SN 1979C is different because it is much closer and belongs to a class of supernovas unlikely to be associated with a GRB. Theory predicts most black holes in the universe should form when the core of a star collapses and a GRB is not produced.

"This may be the first time the common way of making a black hole has been observed," said co-author Abraham Loeb, also of the Harvard-Smithsonian Center for Astrophysics. "However, it is very difficult to detect this type of black hole birth because decades of X-ray observations are needed to make the case."

The idea of a black hole with an observed age of only about 30 years is consistent with recent theoretical work. In 2005, a theory was presented that the bright optical light of this supernova was powered by a jet from a black hole that was unable to penetrate the hydrogen envelope of the star to form a GRB. The results seen in the observations of SN 1979C fit this theory very well.

Although the evidence points to a newly formed black hole in SN 1979C, another intriguing possibility is that a young, rapidly spinning neutron star with a powerful wind of high energy particles could be responsible for the X-ray emission. This would make the object in SN 1979C the youngest and brightest example of such a "pulsar wind nebula" and the youngest known neutron star. The Crab pulsar, the best-known example of a bright pulsar wind nebula, is about 950 years old.

"It's very rewarding to see how the commitment of some of the most advanced telescopes in space, like Chandra, can help complete the story," said Jon Morse, head of the Astrophysics Division at NASA's Science Mission Directorate.

The results will appear in the New Astronomy journal in a paper by Patnaude, Loeb, and Christine Jones of the Harvard-Smithsonian Center for Astrophysics. NASA's Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for the agency's Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra's science and flight operations from Cambridge.

posted 07-23-2014 01:18 PM               

NASA's Chandra X-ray Observatory Celebrates 15th Anniversary

Fifteen years ago, NASA's Chandra X-ray Observatory was launched into space aboard space shuttle Columbia. Since its deployment on July 23, 1999, Chandra has helped revolutionize our understanding of the universe through its unrivaled X-ray vision.

Chandra, one of NASA's current "Great Observatories," along with the Hubble Space Telescope and Spitzer Space Telescope, is specially designed to detect X-ray emission from hot and energetic regions of the universe.

With its superb sensitivity and resolution, Chandra has observed objects ranging from the closest planets and comets to the most distant known quasars. It has imaged the remains of exploded stars, or supernova remnants, observed the region around the supermassive black hole at the center of the Milky Way, and discovered black holes across the universe. Chandra also has made a major advance in the study of dark matter by tracing the separation of dark matter from normal matter in collisions between galaxy clusters. It is also contributing to research on the nature of dark energy.

To celebrate Chandra's 15th anniversary, four new images of supernova remnants – the Crab Nebula, Tycho, G292.0+1.8, and 3C58 – are being released. These supernova remnants are very hot and energetic and glow brightly in X-ray light, which allows Chandra to capture them in exquisite detail.

"Chandra changed the way we do astronomy. It showed that precision observation of the X-rays from cosmic sources is critical to understanding what is going on," said Paul Hertz, NASA's Astrophysics Division director in Washington. "We're fortunate we've had 15 years — so far — to use Chandra to advance our understanding of stars, galaxies, black holes, dark energy, and the origin of the elements necessary for life."

Chandra orbits far above Earth's X-ray absorbing atmosphere at an altitude up to 139,000 km (86,500 mi), allowing for long observations unobscured by Earth's shadow. When it was carried into space in 1999, it was the largest satellite ever launched by the shuttle.

"We are thrilled at how well Chandra continues to perform," said Belinda Wilkes, director of the Chandra X-ray Center (CXC) in Cambridge, Massachusetts. "The science and operations teams work very hard to ensure that Chandra delivers its astounding results, just as it has for the past decade and a half. We are looking forward to more ground-breaking science over the next decade and beyond."

Originally called the Advanced X-ray Astrophysics Facility (AXAF), the telescope was first proposed to NASA in 1976. Prior to its launch aboard the shuttle, the observatory was renamed in honor of the late Indian-American Nobel laureate, Subrahmanyan Chandrasekhar. Known to the world as Chandra (which means "moon" or "luminous" in Sanskrit), he was widely regarded as one of the foremost astrophysicists of the 20th century.

"Chandra continues to be one of the most successful missions that NASA has ever flown as measured against any metric — cost, schedule, technical success and, most of all, scientific discoveries," said Martin Weisskopf, Chandra Project Scientist at the Marshall Space Flight Center in Huntsville, Ala. "It has been a privilege to work on developing and maintaining this scientific powerhouse, and we look forward to many years to come."

posted 10-12-2018 10:54 AM               

Chandra Enters Safe Mode; Investigation Underway

At approximately 9:55 a.m. EDT on Oct. 10, 2018, NASA's Chandra X-ray Observatory entered safe mode, in which the observatory is put into a safe configuration, critical hardware is swapped to back-up units, the spacecraft points so that the solar panels get maximum sunlight, and the mirrors point away from the Sun.

Analysis of available data indicates the transition to safe mode was normal behavior for such an event. All systems functioned as expected and the scientific instruments are safe. The cause of the safe mode transition (possibly involving a gyroscope) is under investigation, and we will post more information when it becomes available.

Chandra is 19 years old, which is well beyond the original design lifetime of 5 years. In 2001, NASA extended its lifetime to 10 years. It is now well into its extended mission and is expected to continue carrying out forefront science for many years to come.

posted 10-15-2018 11:18 AM               

Chandra Operations Resume After Cause of Safe Mode Identified

The cause of Chandra's safe mode on October 10 has now been understood and the Operations team has successfully returned the spacecraft to its normal pointing mode. The safe mode was caused by a glitch in one of Chandra's gyroscopes resulting in a 3-second period of bad data that in turn led the on-board computer to calculate an incorrect value for the spacecraft momentum. The erroneous momentum indication then triggered the safe mode.

The team has completed plans to switch gyroscopes and place the gyroscope that experienced the glitch in reserve. Once configured with a series of pre-tested flight software patches, the team will return Chandra to science operations which are expected to commence by next week.

posted 09-18-2020 04:33 PM               

Chandra X-ray Observatory Returns to Science Operations

NASA's Chandra X-ray Observatory has returned to science operations as teams work towards resolving an anomaly in the High Resolution Camera (HRC) that occurred on Aug. 24.

After isolating an issue to electronics in use since launch in 1999 (far longer than the mission design life of 5 years) the team activated the camera's back-up set of electronics. On Sept. 7, the team turned on the HRC's shield, which tracks radiation levels to protect both the HRC and Chandra's Advanced CCD Imaging Spectrometer (ACIS) instrument from damage.

After confirming that the shield was working and that additional safeguards against radiation damage were in place, Chandra resumed a full schedule of science observations on Sept. 12 using ACIS, which is used for about 95% of Chandra observations. The Chandra science instrument and engineering teams continue to analyze the HRC anomaly and are working to return the camera to normal science operations.

Chandra is now well into its extended mission, and is funded through 2025 with options to extend through 2030.

posted 12-07-2020 04:05 PM               

Chandra Returns to Full Science Operations

On November 23, 2020, the High Resolution Camera (HRC) aboard NASA's Chandra X-ray Observatory officially resumed its full science operations. This followed an anomaly involving the HRC's electronics that was first detected in August 2020. After a switch to the back-up set of electronics in September and systematic study of the HRC's performance with the updated configuration, the anomaly has now been resolved.

Beginning late September and continuing through early November, teams at the Operation Control Center of the Chandra X-ray Center (CXC) ran the HRC through a series of tests to assess how the detector was functioning and determine its performance. This included conducting observations of well-known sources to ensure that systems such as electronics, communications, and data collection behaved as expected. Several different teams analyzed the data to show that the performance of the HRC is excellent.

While the HRC was undergoing testing this fall, Chandra's other instrument, the Advanced CCD Imaging Spectrograph (ACIS), continued taking science observations and collecting data. During the test phase, the HRC was used to observe targets within our Solar System and across the Milky Way. With the HRC back online, the scientific community can once again use the full capabilities of the Chandra X-ray Observatory.

The tests of the HRC's performance were conducted by the CXC HRC operations team and the HRC Instrument Principal Investigator (IPI) team, with support from engineering teams. The investigation of the anomaly with the original HRC electronics is ongoing, and is being conducted by the CXC Operations and IPI teams, the Flight Operations team, Marshall Space Flight Center, and Northrup Grumman.

NASA's Marshall Space Flight Center manages the Chandra program. The Smithsonian Astrophysical Observatory's Chandra X-ray Center controls science and flight operations from Cambridge and Burlington, Massachusetts.