Like many of the most famous objects in the sky, globular cluster Messier 10 was of little interest to its discoverer. Charles Messier, the 18th century French astronomer, cataloged over 100 galaxies and clusters, but was primarily interested in comets. Through the telescopes available at the time, comets, nebulae, globular clusters and galaxies appeared just as faint, diffuse blobs and could easily be confused for one another.
Only by carefully observing their motion — or lack of it — were astronomers able to distinguish them: comets move slowly relative to the stars in the background, while other more distant astronomical objects do not move at all.
Messier's decision to catalog all the objects that he could find, and that were not comets, was a pragmatic solution which would have a huge impact on astronomy. His catalog of just over 100 objects includes many of the most famous objects in the night sky. Messier 10, seen here in an image from the NASA/ESA Hubble Space Telescope, is one of them. Messier described it in the very first edition of his catalog, which was published in 1774 and included the first 45 objects he identified.
Messier 10 is a ball of stars that lies about 15,000 light-years from Earth, in the constellation of Ophiuchus (The Serpent Bearer). Approximately 80 light-years across, it should therefore appear about two thirds the size of the moon in the night sky. However, its outer regions are extremely diffuse, and even the comparatively bright core is too dim to see with the naked eye.
Hubble, which has no problems seeing faint objects, has observed the brightest part of the center of the cluster in this image, a region which is about 13 light-years across.
This image is made up of observations made in visible and infrared light using Hubble's Advanced Camera for Surveys. The observations were carried out as part of a major Hubble survey of globular clusters in the Milky Way.
A version of this image was entered into the Hubble's Hidden Treasures Image Processing Competition by contestant flashenthunder. Hidden Treasures is an initiative to invite astronomy enthusiasts to search the Hubble archive for stunning images that have never been seen by the general public. The competition has now closed and the results will be published soon.
NASA Space Launch System Core Stage Moves From Concept to Design
The nation's space exploration program is taking a critical step forward with a successful major technical review of the core stage of the Space Launch System (SLS), the rocket that will take astronauts farther into space than ever before.
The core stage is the heart of the heavy-lift launch vehicle. It will stand more than 200 feet (61 meters) tall with a diameter of 27.5 feet (8.4 meters).
NASA's Marshall Space Flight Center in Huntsville, Ala., hosted a comprehensive review. Engineers from NASA and The Boeing Co. of Huntsville presented a full set of system requirements, design concepts and production approaches to technical reviewers and the independent review board.
"This meeting validates our design requirements for the core stage of the nation's heavy-lift rocket and is the first major checkpoint for our team," said Tony Lavoie, manager of the SLS Stages Element at Marshall. "Getting to this point took a lot of hard work, and I'm proud of the collaboration between NASA and our partners at Boeing. Now that we have completed this review, we go from requirements to real blueprints. We are right on track to deliver the core stage for the SLS program."
The core stage will store liquid hydrogen and liquid oxygen to feed the rocket's four RS-25 engines, all of which will be former space shuttle main engines for the first few flights. The SLS Program has an inventory of 16 RS-25 flight engines that successfully operated for the life of the Space Shuttle Program. Like the space shuttle, SLS also will be powered initially by two solid rocket boosters on the sides of the launch vehicle.
The SLS will launch NASA's Orion spacecraft and other payloads, and provide an entirely new capability for human exploration beyond low Earth orbit. Designed to be safe, affordable and flexible for crew and cargo missions, the SLS will continue America's journey of discovery and exploration to destinations including nearby asteroids, Lagrange points, the moon and ultimately, Mars.
"This is a very exciting time for the country and NASA as important achievements are made on the most advanced hardware ever designed for human space flight," said William Gerstenmaier, associate administrator for the Human Exploration Operations Mission Directorate at NASA Headquarters in Washington. "The SLS will power a new generation of exploration missions beyond low Earth orbit and the moon, pushing the frontiers of discovery forward. The innovations being made now, and the hardware being delivered and tested, are all testaments to the ability of the U.S. aerospace workforce to make the dream of deeper solar system exploration by humans a reality in our lifetimes."
The first test flight of NASA's Space Launch System, which will feature a configuration for a 77-ton (70-metric-ton) lift capacity, is scheduled for 2017. As SLS evolves, a two-stage launch vehicle configuration will provide a lift capability of 143 tons (130 metric tons) to enable missions beyond low Earth orbit and support deep space exploration.
Boeing is the prime contractor for the SLS core stage, including its avionics. The core stage will be built at NASA's Michoud Assembly Facility in New Orleans using state-of-the-art manufacturing equipment. Marshall manages the SLS Program for the agency.
Across the SLS Program, swift progress is being made on several elements. The J-2X upper-stage rocket engine, developed by Pratt & Whitney Rocketdyne for the future two-stage SLS, is being tested at Stennis Space Center in Mississippi. The prime contractor for the five-segment solid rocket boosters, ATK of Brigham City, Utah, has begun processing its first SLS hardware components in preparation for an initial qualification test in 2013.
Voyager 1 at the Final Frontier
For nearly 35 years, NASA’s Voyager 1 probe has been hurtling toward the edge of the solar system, flying through the dark void on a mission unlike anything attempted before. One day, mission controllers hope, Voyager 1 will leave the solar system behind and enter the realm of the stars—interstellar space.
That day may be upon us.
"The latest data from Voyager 1 indicate that we are clearly in a new region where things are changing quickly," says Ed Stone, Voyager project scientist at the California Institute of Technology in Pasadena. This is very exciting. We are approaching the solar system's final frontier."
The “frontier” he’s referring to is the edge of the heliosphere, a great magnetic bubble that surrounds the sun and planets. The heliosphere is the sun’s own magnetic field inflated to gargantuan proportions by the solar wind. Inside lies the solar system—“home.” Outside lies interstellar space, where no spacecraft has gone before.
A telltale sign of the frontier’s approach is the number of cosmic rays hitting Voyager 1. Cosmic rays are high energy particles such as protons and helium nuclei accelerated to near-light speed by distant supernovas and black holes. The heliosphere protects the solar system from these subatomic bullets, deflecting and slowing many of them before they can reach the inner planets.
As Voyager approaches the frontier, the number of cosmic rays has gone up.
"From January 2009 to January 2012, there had been a gradual increase of about 25 percent in the amount of galactic cosmic rays Voyager was encountering," says Stone.
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