OrbitalHub

Wikipedia dixit:

“The stacked spacecraft will take seven years to position itself to enter Mercury orbit. During this time it will use solar-electric propulsion and nine gravity assists, flying past the Earth and Moon in April 2020, Venus in 2020 and 2021, and six Mercury flybys between 2021 and 2025.

The stacked spacecraft left Earth with an hyperbolic excess velocity of 3.475 km/s (2.159 mi/s). Initially the craft is placed in an orbit similar to that of the Earth. After both the spacecraft and the Earth completed one and a half orbits, it returns to Earth to perform a gravity-assist manoeuvre and is deflected towards Venus. Two consecutive Venus flybys reduce the perihelion nearly to Mercury distance with almost no need for thrust. A sequence of six Mercury flybys will lower the relative velocity to 1.76 km/s (1.09 mi/s). After the fourth Mercury flyby the craft will be in an orbit similar to that of Mercury and will remain in the general vicinity of Mercury. Four final thrust arcs reduce the relative velocity to the point where Mercury will “weakly” capture the spacecraft on 5 December 2025 into polar orbit. Only a small manoeuvre is needed to bring the craft into an orbit around Mercury with an apocentre of 178,000 km. The orbiters then separate and will adjust their orbits using chemical thrusters.”

Video Credit: ESA

Boston Dynamics dixit:

“Atlas does parkour. The control software uses the whole body including legs, arms and torso, to marshal the energy and strength for jumping over the log and leaping up the steps without breaking its pace. (Step height 40 cm.) Atlas uses computer vision to locate itself with respect to visible markers on the approach to hit the terrain accurately.”

Video Credit: Boston Dynamics

NASA dixit:

“Scientists studying what amounts to a computer-simulated “pulsar in a box” are gaining a more detailed understanding of the complex, high-energy environment around spinning neutron stars, also called pulsars. The model traces the paths of charged particles in magnetic and electric fields near the neutron star, revealing behaviors that may help explain how pulsars emit gamma-ray and radio pulses with ultraprecise timing.

A pulsar is the crushed core of a massive star that exploded as a supernova. The core is so compressed that more mass than the Sun’s squeezes into a ball no wider than Manhattan Island in New York City. This process also revvs up its rotation and strengthens its magnetic and electric fields.

Various physical processes ensure that most of the particles around a pulsar are either electrons or their antimatter counterparts, positrons. To trace the behavior and energies of these particles, the researchers used a comparatively new type of pulsar model called a “particle in cell” (PIC) simulation.

The PIC technique lets scientists explore the pulsar from first principles, starting with a spinning, magnetized neutron star. The computer code injects electrons and positrons at the pulsar’s surface and tracks how they interact with the electric and magnetic fields. It’s computationally intensive because the particle motions affect the fields and the fields affect the particles, and everything is moving near the speed of light.

The simulation shows that most of the electrons tend to race outward from the magnetic poles. Some medium-energy electrons scatter wildly, even heading back to the pulsar. The positrons, on the other hand, mostly flow out at lower latitudes, forming a relatively thin structure called the current sheet. In fact, the highest-energy positrons here — less than 0.1 percent of the total — are capable of producing gamma rays similar to those detected by NASA’s Fermi Gamma-ray Space Telescope, which has discovered 216 gamma-ray pulsars.”

Video Credit: NASA Goddard

NASA dixit:

“Working from a combination of satellite records and declassified submarine sonar data, NASA scientists have constructed a 60-year record of Arctic sea ice thickness. Right now, Arctic sea ice is the youngest and thinnest its been since we started keeping records. More than 70 percent of Arctic sea ice is now seasonal, which means it grows in the winter and melts in the summer, but doesn’t last from year to year. This seasonal ice melts faster and breaks up easier, making it much more susceptible to wind and atmospheric conditions.”

Video Credit: NASA Goddard

ULA dixit:

“United Launch Alliance will use an Atlas V 551 rocket to launch the fourth communications satellite in the Advanced Extremely High Frequency (AEHF) series for the U.S. Air Force. The launch is scheduled for 10/17. The window opens at 12:15 a.m. EDT.

AEHF satellites provide highly-secure, jam-proof connectivity between U.S. national leadership and deployed military forces. Atlas V rockets successfully launched the first three AEHF satellites in 2010, 2012 and 2013 as the new constellation was formed in geosynchronous orbit 22,300 miles above Earth.

This will be 131st mission for United Launch Alliance and our 50th launch for the Air Force. It is the 79th for an Atlas V rocket and the 9th in the 551 configuration.”

Video Credit: ULA

NASA dixit:

“NASA astronaut Nick Hague and Russian cosmonaut Alexey Ovchinin are in good condition following an aborted launch of their Soyuz spacecraft.

The Soyuz MS-10 spacecraft launched from the Baikonur Cosmodrome in Kazakhstan to the International Space Station at 4:40 a.m. EDT Thursday, October 11 (2:40 p.m. in Baikonur) carrying American astronaut Nick Hague and Russian cosmonaut Alexey Ovchinin. Shortly after launch, there was an anomaly with the booster and the launch ascent was aborted, resulting in a ballistic landing of the spacecraft. Search and rescue teams were deployed to the landing site. Hague and Ovchinin are out of the capsule and are reported to be in good condition.”

Video Credit: Roscosmos/NASA