NASAs low-Earth orbiting rockets get hardware boost

What in news:

  Engineers have now assembled the first major piece of core stage hardware for NASAs Space Launch System (SLS) rocket which is designed to herald a new era of exploration beyond low-Earth orbit.


  Engineers have now assembled the first major piece of core stage hardware for NASAs Space Launch System (SLS) rocket

  It is designed to herald a new era of exploration beyond low-Earth orbit, launching crew and cargo on deep space exploration missions to the Moon, Mars and beyond.

  It now is ready to be joined with other hardware for Exploration Mission-1, the first integrated flight of SLS and the Orion spacecraft.

  The 212-foot-tall core stage, referred to as the backbone of the rocket by NASA, will contain the SLS rockets four RS-25 rocket engines, propellant tanks, flight computers and much more.

  Though the smallest part of the core stage, the forward skirt will serve two critical roles.

  It will connect the upper part of the rocket to the core stage and house many of the flight computers, or avionics.

  Completion of the core stage forward skirt is a major step in NASAs progress to the launch pad.

  Were putting into practice the steps and processes needed to assemble the largest rocket stage ever built.

  With the forward skirt, we are improving and refining how well conduct final assembly of the rest of the rocket.

  As part of forward skirt testing, the flight computers came to life for the first time as NASA engineers tested critical avionic systems that will control the rockets flight.

  Located throughout the core stage, the avionics are the rockets brains, controlling navigation and communication during launch and flight.

  It is critical that each of the avionics units is installed correctly, work as expected and communicate with each other and other components, including the Orion spacecraft and ground support systems.

  It was amazing to see the computers come to life for the first time, said Lisa Espy, lead test engineer for SLS core stage avionics.

  Orbit: An orbit is a regular, repeating path that one object in space takes around another one

  Heliocentric orbit: An orbit around the Sun. In the Solar System, all planets, comets, and asteroids are in such orbits, as are many artificial satellites and pieces of space debris.

  Geocentric orbit: An orbit around the planet Earth, such as that of the Moon or of artificial satellites.

  Low Earth orbit (LEO):Low earth orbits (LEO) are satellite systems used in telecommunication, which orbit between 400 and 1,000 miles above the earth's surface.

  Geosynchronous orbit (GSO): A geosynchronous orbit is a high Earth orbit that allows satellites to match Earth's rotation. Located at 22,236 miles (35,786 kilometers) above

  Geostationary orbit (GEO): A geostationary orbit, often referred to as a geosynchronous equatorial orbit (GEO), is a circular geosynchronous orbit 35,786 km (22,236 mi) above Earth's equator and following the direction of Earth's rotation.

        Geostationary orbits are also geosynchronous, but not all geosynchronous orbits are geostationary.

        A geostationary orbit stays exactly above the equator, whereas a geosynchronous orbit may swing north and south to cover more of the Earth's surface.

        Both complete one full orbit of Earth per sidereal day





  Polar orbit:An orbit that passes above or nearly above both poles of the planet on each revolution. Therefore, it has an inclination of (or very close to) either 90 degrees or -90 degrees.

  Polar Sun-synchronous orbit (SSO): A nearly polar orbit that passes the equator at the same local solar time on every pass. Useful for image-taking satellites because shadows will be the same on every pass.

  Geostationary or Geosynchronus Transfer orbit (GTO):An elliptic orbit where the perigee is at the altitude of a low Earth orbit (LEO) and the apogee at the altitude of a geostationary orbit.

Expected prelims question:

Communication satellites are generally placed in

a)      Low earth orbit

b)      Middle earth orbit

c)      High earth orbit

d)      None of the above

Ans - a

Expected mains question:

Discuss the various types of orbits. Add a note on why many countries uses varied orbits to launch its satellites.