OrbitalHub

Wikipedia dicit:

The Proton-M launch vehicle consists of three stages; all of them powered by liquid rocket engines using the hypergolic propellant combination of dinitrogen tetroxide as the oxidizer, and unsymmetrical dimethylhydrazine for fuel.

The first stage is unique in that it consists of a central cylindrical oxidizer tank with the same diameter as the other two stages with six fuel tanks attached to its circumference, each carrying an engine. The engines in this stage can swivel tangentially up to 7° from the neutral position, providing full thrust vector control. The rationale for this design is logistics: the diameter of the oxidizer tanks and the two following stages is the maximum that can be delivered by railroad to Baikonur. However, within Baikonur the fully assembled stack is transported again by rail, as it has enough clearance.

The second stage uses a conventional cylindrical design. It is powered by three RD-0210 engines and one RD-0211 engine. The RD-0211 is a modified version of the RD-0210 used to pressurize the propellant tanks. The second stage is joined to the first stage through a net instead of a closed inter-stage, to allow the exhaust to escape because the second stage begins firing seconds before separation. Thrust vector control is provided by engine gimballing.

The third stage is also of a conventional cylindrical design. It contains the avionics system that controls the first two stages. It uses one RD-0213 which is a fixed (non-gimballed) version of the RD-0210, and one RD-0214 which is a four nozzle vernier engine used for thrust vector control. The nozzles of the RD-0214 can turn up to 45°; they are placed around (with some separation), and moderately above the nozzle of the RD-0213.

The Proton-M features modifications to the lower stages to reduce structural mass, increase thrust, and utilise more propellant (less of it remains unused in the tanks). A closed-loop guidance system is used on the first stage, which allows more complete consumption of propellant. This increases the rocket’s performance slightly compared to previous variants, and reduces the amount of toxic chemicals remaining in the stage when it impacts downrange. It can place up to 21 tonnes (46,000 lb) into low Earth orbit. With an upper stage, it can place a 3 tonne payload into geosynchronous orbit, or a 5.5 tonne payload into geosynchronous transfer orbit. Efforts were also made to reduce dependency on foreign component suppliers.

Video Credit: Roscosmos

Wikipedia dicit:

Yamal 601 (Russian: Ямал-601) is a geostationary communications satellite ordered by Gazprom Space Systems to ISS Reshetnev on the Ekspress-2000 platform for its Yamal program. The Ekspress-2000 platform is the heavy version, which can weigh up to 3,500 kg (7,700 lb) and generate up to 14 kW of power on an unpressurized bus designed for direct GEO injection with 15 years of design life. Its payload will be supplied by Thales Alenia Space and is composed of 38 C band, and 32 Ka band transponders. It will replace Yamal 202 on 49°E when it reaches its end of service around 2018.

Video Credit: Roscosmos

NASA dicit:

Astronomers using NASA’s Fermi Gamma-ray Space Space Telescope and the National Science Foundation’s Karl G. Jansky Very Large Array (VLA) have found a pulsar hurtling through space at nearly 2.5 million miles an hour — so fast it could travel the distance between Earth and the Moon in just 6 minutes.

Pulsars are superdense, rapidly spinning neutron stars left behind when a massive star explodes. This one, dubbed PSR J0002+6216 (J0002 for short), sports a radio-emitting tail pointing directly toward the expanding debris from a recent supernova explosion. Thanks to its narrow dart-like tail and a fortuitous viewing angle, astronomers can trace this pulsar straight back to its birthplace. Further study of J0002 will help us better understand how these explosions are able to ‘kick’ neutron stars to such high speed.

The pulsar is located about 6,500 light-years away in the constellation Cassiopeia. It was discovered in 2017 by a citizen-science project called Einstein@Home , which uses downtime on the computers of volunteers to process Fermi gamma-ray data and has identified 23 gamma-ray pulsars to date. J0002 spins 8.7 times a second, producing a pulse of gamma rays with each rotation, and has about 1.5 times the mass of the Sun. The pulsar lies about 53 light-years from the center of a supernova remnant called CTB 1. Its rapid motion through interstellar gas results in shock waves that produce the tail of magnetic energy and accelerated particles detected at radio wavelengths using the VLA. The tail extends 13 light-years and clearly points back to the center of CTB 1.

Using Fermi data and a technique called pulsar timing, the team was able to measure how quickly and in what direction the pulsar was moving across our line of sight thanks to Fermi’s 10-year data covering the entire sky. J0002 is speeding through space five times faster than the average pulsar and faster than 99 percent of those with measured speeds. It will eventually escape our galaxy.

Francis Reddy (University of Maryland College Park): Lead Science Writer

Scott Wiessinger (USRA): Lead Producer

Jeanette Kazmierczak (University of Maryland College Park): Science Writer

Music credit: “Forensic Scientist” from Killer Tracks

Video Credit: NASA Goddard

Wikipedia dicit:

A Van Allen radiation belt is a zone of energetic charged particles, most of which originate from the solar wind, that are captured by and held around a planet by that planet’s magnetic field. Earth has two such belts and sometimes others may be temporarily created. The discovery of the belts is credited to James Van Allen, and as a result, Earth’s belts are known as the Van Allen belts. Earth’s two main belts extend from an altitude of about 640 to 58,000 km (400 to 36,040 mi) above the surface in which region radiation levels vary. Most of the particles that form the belts are thought to come from solar wind and other particles by cosmic rays. By trapping the solar wind, the magnetic field deflects those energetic particles and protects the atmosphere from destruction.

The belts are located in the inner region of Earth’s magnetosphere. The belts trap energetic electrons and protons. Other nuclei, such as alpha particles, are less prevalent. The belts endanger satellites, which must have their sensitive components protected with adequate shielding if they spend significant time near that zone. In 2013, NASA reported that the Van Allen Probes had discovered a transient, third radiation belt, which was observed for four weeks until it was destroyed by a powerful, interplanetary shock wave from the Sun.

Video Credit: NASA

NASA dicit:

On June 19, 2004, NASA launches Aura, a next generation Earth-observing satellite. One of several instruments on the Aura satellite is the Ozone Monitoring Instrument (OMI). OMI is a contribution of the Netherland’s Agency for Aerospace Programs (NIVR) along with the Finnish Meteorological Institute (FMI). OMI will continue the TOMS record for total ozone and other atmospheric parameters related to ozone chemistry and climate.

Video Credit: NASA

NASA dicit:

The International Space Station’s High Definition Earth Viewing (HDEV) experiment is an external camera platform located on the Columbus module of the space station. In addition to providing beautiful views of Earth, one of the goals of HDEV is to monitor the longevity and quality of its image sensors in the space environment. HDEV operations began April 30, 2014 and only a single bad pixel has been identified.

Video Credit: NASA Johnson