OrbitalHub

NASA dixit:

“This supercomputer simulation shows one of the most violent events in the universe: a pair of neutron stars colliding, merging and forming a black hole. A neutron star is the compressed core left behind when a star born with between eight and 30 times the sun’s mass explodes as a supernova. Neutron stars pack about 1.5 times the mass of the sun — equivalent to about half a million Earths — into a ball just 12 miles (20 km) across.

As the simulation begins, we view an unequally matched pair of neutron stars weighing 1.4 and 1.7 solar masses. They are separated by only about 11 miles, slightly less distance than their own diameters. Redder colors show regions of progressively lower density.

As the stars spiral toward each other, intense tides begin to deform them, possibly cracking their crusts. Neutron stars possess incredible density, but their surfaces are comparatively thin, with densities about a million times greater than gold. Their interiors crush matter to a much greater degree densities rise by 100 million times in their centers. To begin to imagine such mind-boggling densities, consider that a cubic centimeter of neutron star matter outweighs Mount Everest.

By 7 milliseconds, tidal forces overwhelm and shatter the lesser star. Its superdense contents erupt into the system and curl a spiral arm of incredibly hot material. At 13 milliseconds, the more massive star has accumulated too much mass to support it against gravity and collapses, and a new black hole is born. The black hole’s event horizon — its point of no return — is shown by the gray sphere. While most of the matter from both neutron stars will fall into the black hole, some of the less dense, faster moving matter manages to orbit around it, quickly forming a large and rapidly rotating torus. This torus extends for about 124 miles (200 km) and contains the equivalent of 1/5th the mass of our sun. The entire simulation covers only 20 milliseconds.

Scientists think neutron star mergers like this produce short gamma-ray bursts (GRBs). Short GRBs last less than two seconds yet unleash as much energy as all the stars in our galaxy produce over one year.

The rapidly fading afterglow of these explosions presents a challenge to astronomers. A key element in understanding GRBs is getting instruments on large ground-based telescopes to capture afterglows as soon as possible after the burst. The rapid notification and accurate positions provided by NASA’s Swift mission creates a vibrant synergy with ground-based observatories that has led to dramatically improved understanding of GRBs, especially for short bursts.”

Credit: NASA Goddard

NASA dixit:

“The historic 1964 Ranger 7 mission was the first true success in the United States’ early quest to explore the moon.
The JPL-built spacecraft launched July 28. Three days later, it made a targeted impact on the moon, sending back more than 4,300 photos along the way.”

Credit: NASA

NASA dixit:

“Carrying more than 3,000 pounds of food, supplies, spare parts and experiments, Orbital Sciences Corporation’s Cygnus cargo ship arrived at the International Space Station July 16, where it was grappled by Expedition 40 Commander Steve Swanson backed up by European Space Agency Flight Engineer Alexander Gerst. The pair operated the Canadarm2 robotic arm from the station’s cupola to snag Cygnus before robotic ground controllers admission control in Houston initiated its installation onto the Earth-facing port of the Harmony module where it would be bolted in place for a month-long stay. Cygnus was launched July 13 atop Orbital’s Antares rocket from the Mid-Atlantic Regional Spaceport’s Launch Pad 0A at Wallops Flight Facility, Virginia for the second contracted commercial resupply flight for the U.S. firm.”

Credit: NASA

 

NASA dixit:

“NASA marks the 45th anniversary of the first moon landing this month while it takes the steps needed for America’s next giant leap to send astronauts to Mars. Mission Video shown is as aired in July 1969 depicting the Apollo 11 astronauts conducting several tasks during extravehicular activity (EVA) operations on the surface of the moon as well as pre-lauch preparations and post launch activities and celebrations.”

Credit: NASA

NASA dixit:

“NASA’s first spacecraft dedicated to studying carbon dioxide in Earth’s atmosphere was successfully launched from Vandenberg Air Force Base, California. OCO-2 will be collecting a great number of high-resolution measurements, which will provide a greater spatial distribution of CO2 over the entire globe, in short, a bigger, clearer, more complete picture of global CO2. These measurements will be combined with data from the ground-based network to provide scientists with the information that they need to better understand the processes that regulate atmospheric CO2 and its role in the carbon cycle.”

Credit: NASA

 

NASA dixit:

“[…] the four spacecraft fly in a tetrahedron formation. This complex arrangement enables scientists to gather data about magnetic reconnection in 3D.

On its journey, MMS will observe a little-understood, but universal phenomenon called magnetic reconnection, responsible for dramatic re-shaping of the magnetic environment near Earth, often sending intense amounts of energy and fast-moving particles off in a new direction. Not only is this a fundamental physical process that occurs throughout the universe, it is also one of the drivers of space weather events at Earth. Truly understanding the process requires four identical spacecraft to track how such reconnection events move across and through any given space.”

Credit: NASA

Read more about the MMS mission…