Washington: The US space agency has successfully installed the first of 18 flight mirrors onto the James Webb Space Telescope, beginning a critical piece of the observatory's construction to replace the Hubble Space Telescope by 2018. After being pieced together, the 18 primary mirror segments will work together as one large 21.3-foot mirror. The full installation is expected to be complete early next year. "The James Webb Space Telescope will be the premier astronomical observatory of the next decade," said John Grunsfeld, astronaut and associate administrator of the Science Mission Directorate at NASA headquarters in Washington, DC, in a statement. This first-mirror installation milestone symbolises all the new and specialised technology that was developed to enable the observatory to study the first stars and galaxies, provide answers to the evolution of our own solar system and make the next big steps in the search for life beyond Earth on exoplanets. Several innovative technologies have been developed for the Webb Telescope that is targeted for launch in 2018. Webb will study every phase in the history of our universe, including the cosmos' first luminous glows, the formation of solar systems capable of supporting life on planets like Earth, and the evolution of our own solar system. The 18 separate segments unfold and adjust to shape after launch. The mirrors are made of ultra-lightweight beryllium chosen for its thermal and mechanical properties at cryogenic temperatures. Each segment also has a thin gold coating chosen for its ability to reflect infrared light. The telescope's biggest feature is a tennis court sized five-layer sunshield that attenuates heat from the sun more than a million times. The mirrors must remain precisely aligned in space in order for Webb to successfully carry out science investigations. While operating at extraordinarily cold temperatures, the backplane must not move more than 38 nanometers, approximately one thousandth the diameter of a human hair. — IANS. Source: Article
NASA set to replace Hubble with James Webb telescope in three years
Washington: The US space agency has successfully installed the first of 18 flight mirrors onto the James Webb Space Telescope, beginning a critical piece of the observatory's construction to replace the Hubble Space Telescope by 2018. After being pieced together, the 18 primary mirror segments will work together as one large 21.3-foot mirror. The full installation is expected to be complete early next year. "The James Webb Space Telescope will be the premier astronomical observatory of the next decade," said John Grunsfeld, astronaut and associate administrator of the Science Mission Directorate at NASA headquarters in Washington, DC, in a statement. This first-mirror installation milestone symbolises all the new and specialised technology that was developed to enable the observatory to study the first stars and galaxies, provide answers to the evolution of our own solar system and make the next big steps in the search for life beyond Earth on exoplanets. Several innovative technologies have been developed for the Webb Telescope that is targeted for launch in 2018. Webb will study every phase in the history of our universe, including the cosmos' first luminous glows, the formation of solar systems capable of supporting life on planets like Earth, and the evolution of our own solar system. The 18 separate segments unfold and adjust to shape after launch. The mirrors are made of ultra-lightweight beryllium chosen for its thermal and mechanical properties at cryogenic temperatures. Each segment also has a thin gold coating chosen for its ability to reflect infrared light. The telescope's biggest feature is a tennis court sized five-layer sunshield that attenuates heat from the sun more than a million times. The mirrors must remain precisely aligned in space in order for Webb to successfully carry out science investigations. While operating at extraordinarily cold temperatures, the backplane must not move more than 38 nanometers, approximately one thousandth the diameter of a human hair. — IANS. Source: Article
NASA camera reveals 'dark side' of moon
Washington: From nearly 1.6 lakh km away, a NASA camera has captured a stunning view of the far side of the moon as it moved in front of the sun-lit side of Earth last month. The images show the fully illuminated “dark side” of the moon that is never visible from Earth. The lunar far side lacks the large and dark basaltic plains (called maria) that are so prominent on the Earth-facing side. A thin sliver of shadowed area of moon is visible on its right side. "It is surprising how much brighter Earth is than the moon. Our planet is a truly brilliant object in dark space compared to the lunar surface,” said said Adam Szabo, project scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. The images were captured by NASA's Earth Polychromatic Imaging Camera (EPIC), a four megapixel CCD camera and telescope aboard the Deep Space Climate Observatory (DSCOVR) satellite orbiting 1 million miles (1.6 lakh km) from Earth. EPIC maintains a constant view of the fully-illuminated Earth as it rotates, providing scientific observations of ozone, vegetation, cloud height and aerosols in the atmosphere. The far side of the moon was not seen until 1959 when the Soviet Luna 3 spacecraft returned the first images. Since then, several NASA missions have imaged the lunar far side in great detail. The same side of the moon always faces an earthbound observer because the moon is tidally locked to Earth. That means its orbital period is the same as its rotation around its axis. Once EPIC begins regular observations next month, NASA will post daily colour images of Earth to a dedicated public website. About twice a year, the camera will capture the moon and Earth together as the orbit of DSCOVR crosses the orbital plane of the moon. Source: ummid.com, Image: flickr.com
Beyond Pluto: New Horizons targets identified
NASA has announced finding several Kuiper Belt Objects that may be targeted by the New Horizons spacecraft, following its flyby of the Pluto system in July 2015.
Peering into the dim, outer reaches of our Solar System, NASA's Hubble Space Telescope has uncovered three Kuiper Belt Objects (KBOs) that the agency's New Horizons spacecraft could potentially visit after it flies by Pluto in July 2015. The KBOs were detected by a search team who were awarded telescope time for this purpose, following a committee recommendation earlier this year. "This has been a very challenging search, and it's great that in the end Hubble could accomplish a detection — one NASA mission helping another," said Alan Stern of the Southwest Research Institute (SwRI) in Boulder, Colorado, principal investigator of the New Horizons mission. The Kuiper Belt is a vast rim of primordial debris encircling our Solar System. KBOs belong to a unique class of Solar System objects that has never been visited by spacecraft and which contain clues to the origin of our Solar System. The KBOs that Hubble found are each about 10 times larger than typical comets, but only about 1-2 percent of
the size of Pluto. Unlike asteroids, KBOs have not been heated by the Sun, and are thought to represent a pristine, well preserved, deep-freeze sample of what the outer Solar System was like following its birth 4.6 billion years ago. The KBOs found in the Hubble data are thought to be the building blocks of dwarf planets such as Pluto. The New Horizons team started to look for suitable KBOs in 2011 using some of the largest ground-based telescopes on Earth. They found several dozen KBOs, but none were reachable within the fuel supply available aboard the New Horizons spacecraft. "We started to get worried that we could not find anything suitable – even with Hubble – but in the end, the space telescope came to the rescue," said team member John Spencer of SwRI. "There was a huge sigh of relief when we found suitable KBOs; we are 'over the moon' about this detection." Source: Article
the size of Pluto. Unlike asteroids, KBOs have not been heated by the Sun, and are thought to represent a pristine, well preserved, deep-freeze sample of what the outer Solar System was like following its birth 4.6 billion years ago. The KBOs found in the Hubble data are thought to be the building blocks of dwarf planets such as Pluto. The New Horizons team started to look for suitable KBOs in 2011 using some of the largest ground-based telescopes on Earth. They found several dozen KBOs, but none were reachable within the fuel supply available aboard the New Horizons spacecraft. "We started to get worried that we could not find anything suitable – even with Hubble – but in the end, the space telescope came to the rescue," said team member John Spencer of SwRI. "There was a huge sigh of relief when we found suitable KBOs; we are 'over the moon' about this detection." Source: Article
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