Happy 25th Birthday Buran!

Happy 25th Birthday Buran! The only orbital launch of Buran occurred at 3:00 UTC on 15 November 1988 from Baikonur Cosmodrome Site 110/37. It was lifted into orbit unmanned by the specially designed Energia rocket. Buran was the first space shuttle to perform an unmanned flight, including landing in fully automatic mode.
The unmanned flight was the first time that a spacecraft of this size and complexity had been launched, completed maneuvers in orbit, re-entered the atmosphere, and landed under automatic guidance
(Energia)

INDIA'S MARS ORBITERS MISSION

 

PSLV puts Mars orbiter precisely into earth-orbit; trip to the Red Planet will take more than 300 days

The nation’s prestigious interplanetary mission to Mars, 40 crore km away, got off to a flying start on Tuesday when the Indian Space Research Organisation’s trusty Polar Satellite Launch Vehicle (PSLV-C25) roared off the first launch pad of the spaceport at Sriharikota at 2.38 p.m. and put the Mars orbiter precisely into its earth-orbit about 44 minutes later.

This was the first crucial and difficult step in the ISRO’s Mars Orbiter Mission. However, the XL version of the PSLV achieved it with aplomb. The elliptical orbit achieved was so accurate that against the predicted perigee of 250 km and an apogee of 23,500 km, it went into an orbit of 246.9 km x 23,566 km.

The spacecraft first going into orbit around the earth signalled the start of its 300-day voyage to the Red Planet. If everything goes well during this complex and challenging journey through deep space, it will be put into the Mars orbit on September 24, 2014.

Mission highlights

Two mission highlights are: it was the longest PSLV mission at 44 minutes — the previous missions lasted about 18 minutes, and this was the silver jubilee lift-off of the PSLV. Out of the 25 launches, 24 had been successful in a row.

Suspense filled the newly-built Mission Control Centre (MCC) when there was a long coasting phase of 25 minutes between the PSLV’s third stage burnout and the fourth stage ignition.

Tension gripped the MCC again for about half-a-minute for it was only 37 seconds after the fourth stage burnout that the spacecraft was put into orbit. But all this was as planned.

The ISRO scientists’ cup of joy overflowed when M.S. Pannirselvam, Range Operations Director, PSLV-C25, announced tersely from the MCC, “Spacecraft separation achieved. It has been successfully put into orbit.”

Asked later how he felt when he made the announcement, he said, “We had no feeling. We were doing our job.”

Applause erupted when ISRO Chairman K. Radhakrishnan, who did not hide his joy, turned towards his colleagues in the MCC and acknowledged their cheers with folded hands. He called the flight a copybook and textbook mission. It was a new and complex mission in design and execution, he said.

Project Director of Mars Orbiter S. Arunan called it an “excellent mission.” The primary and secondary panels and the high gain antenna of the spacecraft had been deployed. “The spacecraft is in good heath,” he said.

Yash Pal, former Member of the Space Commission, called the successful mission ISRO’s “very very special gift to the nation.”

Long way to go

All former and present brass of ISRO tried to temper the delight by cautioning that “there was a long way to go in time and distance” before the orbiter was put into the Martian orbit in September 2014. They included present top engineers S. Ramakrishnan, M.Y.S. Prasad, A.S. Kiran Kumar, S.K. Shivakumar, M.C. Dathan, P. Kunhikrishnan and the former ISRO chairmen, U.R. Rao and K. Kasturirangan. They emphasised that “while the first job has been successfully done, a long journey lies ahead.”

Objectives
The primary objective of the Mars Orbiter Mission is to showcase India's rocket launch systems, spacecraft-building and operations capabilities. Specifically, the primary objective is to develop the technologies required for design, planning, management and operations of an interplanetary mission, comprising the following major tasks
    Design and realisation of a Mars orbiter with a capability to perform Earth bound manoeuvres, cruise phase of 300 days, Mars orbit insertion / capture, and on-orbit phase around Mars.
    Deep space communication, navigation, mission planning and management.
    Incorporate autonomous features to handle contingency situations.

The secondary objective is to explore Mars' surface features, morphology, mineralogy and Martian atmosphere using indigenous scientific instruments.

Spacecraft

The spacecraft structure and propulsion hardware configurations are similar to Chandrayaan 1, India's first successful robotic lunar orbiter that operated from 2008 to 2009, with specific improvements and upgrades needed for a Mars specific mission.

Mass
    The lift-off mass was 1350 kg, including 852 kg of propellant mass.
Dimensions
    Cuboid in shape of approximately 1.5 m
Bus
    The spacecraft's bus is a modified I-1 K structure and propulsion hardware configurations similar to Chandrayaan 1, India's successful lunar orbiter that operated from 2008 to 2009, with specific improvements and upgrades needed for a Mars mission. The satellite structure is of aluminum and composite fiber reinforced plastic (CFRP) sandwich construction.
Power
    Electric power is generated by three solar array panels of 1.8 m X 1.4 m each (7.56 m2 total), for a maximum of 840 W generation in Martian orbit. Electricity is stored in a 36 Ah Li-ion battery.

Propulsion
    Liquid fuel engine of 440 N thrust is used for orbit raising and insertion in Martian orbit.
Communications
    Two 230 W TWTAs and two coherent transponders. The antenna array consists of a Low-gain antenna, a Medium-gain antenna and a High-gain antenna. The High-gain antenna system is based on a single 2.2 meter reflector illuminated by a feed at S-band. It is used to transmit and receive the telemetry, tracking, commanding and data to and from the Indian Deep Space Network.

Payload

The 15 kg (33 lb) scientific payload consists of five instruments:

Atmospheric studies

    Lyman-Alpha Photometer (LAP) — a photometer that measures the relative abundance of deuterium and hydrogen from Lyman-alpha emissions in the upper atmosphere. Measuring the deuterium/hydrogen ratio will allow the amount of water loss to outer space to be estimated.
    Methane Sensor For Mars (MSM) — will measure methane in the atmosphere of Mars, if any, and map its sources.

Particle environment studies

    Mars Exospheric Neutral Composition Analyzer (MENCA) — is a quadrupole mass analyzer capable of analyzing the neutral composition of particles in the exosphere.

Surface imaging studies

    Thermal Infrared Imaging Spectrometer (TIS) — will measure the temperature and emissivity of the Martian surface, allowing for the mapping of surface composition and mineralogy of Mars.
    Mars Color Camera (MCC) — will provide images in the visual spectrum, providing context for the other instruments

NASA begins deepest ever probe of the universe

NASA’s Hubble, Spitzer and Chandra space telescopes are teaming up to look deeper into the universe than ever before and search for the most distant and faint galaxies that can possibly be seen.
With a boost from natural “zoom lenses” found in space, they should be able to uncover galaxies that are as much as 100 times fainter than what these three great observatories typically can see, NASA said.
In a collaborative programme called The Frontier Fields, astronomers will make observations over the next three years of six massive galaxy clusters, exploiting a natural phenomenon known as gravitational lensing.
The clusters are among the most massive assemblages of matter known, and their gravitational fields can be used to brighten and magnify more distant galaxies so they can be observed.
“The Frontier Fields programme is exactly what NASA’s great observatories were designed to do; working together to unravel the mysteries of the Universe,” said John Grunsfeld, associate administrator for NASA’s Science Mission Directorate in Washington.
“Each observatory collects images using different wavelengths of light with the result that we get a much deeper understanding of the underlying physics of these celestial objects,” Grunsfeld said in a statement.
The first object they will view is Abell 2744, commonly known as Pandora’s Cluster. The galaxy cluster is the result of a simultaneous pile-up of four separate, smaller galaxy clusters that took place over a span of 350 million years.
Astronomers anticipate the observations will reveal populations of galaxies that existed when the universe was only a few hundred million years old.
“The idea is to use nature’s natural telescopes in combination with the great observatories to look much deeper than before and find the most distant and faint galaxies we can possibly see,” said Jennifer Lotz, a principal investigator with the Space Telescope Science Institute in Baltimore.
Data from the Hubble and Spitzer space telescopes will be combined to measure the galaxies’ distances and masses more accurately than either observatory could measure alone, demonstrating their synergy for such studies.
“We want to understand when and how the first stars and galaxies formed in the universe, and each great observatory gives us a different piece of the puzzle,” said Peter Capak, the Spitzer principal investigator for the Frontier Fields programme.
“Hubble tells you which galaxies to look at and how many stars are being born in those systems. Spitzer tells you how old the galaxy is and how many stars have formed,” Capak said.
The Chandra X-ray Observatory also will peer deep into the star fields. It will image the clusters at X-ray wavelengths to help determine their mass and measure their gravitational lensing power, and identify background galaxies hosting super massive black holes.

Missiles

In a modern military, a missile is a self-propelled guided weapon system, as opposed to an unguided self-propelled munition, referred to as just a rocket. Missiles have four system components: targeting and/or guidance, flight system, engine, and warhead. Missiles come in types adapted for different purposes: surface-to-surface and air-to-surface missiles (ballistic, cruise, anti-ship, anti-tank, etc.), surface-to-air missiles (anti-aircraft and anti-ballistic), air-to-air missiles, and anti-satellite missiles. All known existing missiles are designed to be propelled during powered flight by chemical reactions inside a rocket engine, jet engine, or other type of engine.[citation needed] Non-self-propelled airborne explosive devices are generally referred to as shells and usually have a shorter range than missiles.

Guidance systems

 Missile guidance

Missiles may be targeted in a number of ways. The most common method is to use some form of radiation, such as infrared, lasers or radio waves, to guide the missile onto its target. This radiation may emanate from the target (such as the heat of an engine or the radio waves from an enemy radar), it may be provided by the missile itself (such as a radar) or it may be provided by a friendly third party (such as the radar of the launch vehicle/platform, or a laser designator operated by friendly infantry). The first two are often known as fire-and-forget as they need no further support or control from the launch vehicle/platform in order to function. Another method is to use a TV camera—using either visible light or infra-red—in order to see the target. The picture may be used either by a human operator who steers the missile onto its target, or by a computer doing much the same job. One of the more bizarre guidance methods instead used a pigeon to steer the missile to its target.
Many missiles use a combination of two or more of the above methods, to improve accuracy and the chances of a successful engagement.

Targeting systems

Another method is to target the missile by knowing the location of the target, and using a guidance system such as INS, TERCOM or GPS. This guidance system guides the missile by knowing the missile's current position and the position of the target, and then calculating a course between them. This job can also be performed somewhat crudely by a human operator who can see the target and the missile, and guides it using either cable or radio based remote-control, or by an automatic system that can simultaneously track the target and the missile. Furthermore, some missiles use initial targeting, sending them to a target area, where they will switch to primary targeting, using either radar or IR targeting to acquire the target.

Flight system

Whether a guided missile uses a targeting system, a guidance system or both, it needs a flight system. The flight system uses the data from the targeting or guidance system to maneuver the missile in flight, allowing it to counter inaccuracies in the missile or to follow a moving target. There are two main systems: vectored thrust (for missiles that are powered throughout the guidance phase of their flight) and aerodynamic maneuvering (wings, fins, canards, etc.).

Engine

Missiles are powered by an engine, generally either a type of rocket or jet engine. Rockets are generally of the solid fuel type for ease of maintenance and fast deployment, although some larger ballistic missiles use liquid fuel rockets. Jet engines are generally used in cruise missiles, most commonly of the turbojet type, due to its relative simplicity and low frontal area. Turbofans and ramjets are the only other common forms of jet engine propulsion, although any type of engine could theoretically be used. Missiles often have multiple engine stages, particularly in those launched from the surface. These stages may all be of similar types or may include a mix of engine types - for example, surface-launched cruise missiles often have a rocket booster for launching and a jet engine for sustained flight.
Some missiles may have additional propulsion from another source at launch; for example the V1 was launched by a catapult and the MGM-51 was fired out of a tank gun (using a smaller charge than would be used for a shell).

Warhead

Missiles generally have one or more explosive warheads, although other weapon types may also be used. The warhead or warheads of a missile provides its primary destructive power (many missiles have extensive secondary destructive power due to the high kinetic energy of the weapon and unburnt fuel that may be on board). Warheads are most commonly of the high explosive type, often employing shaped charges to exploit the accuracy of a guided weapon to destroy hardened targets. Other warhead types include submunitions, incendiaries, nuclear weapons, chemical, biological or radiological weapons or kinetic energy penetrators. Warheadless missiles are often used for testing and training purposes.

Basic roles

Missiles are generally categorized by their launch platform and intended target. In broadest terms, these will either be surface (ground or water) or air, and then sub-categorized by range and the exact target type (such as anti-tank or anti-ship). Many weapons are designed to be launched from both surface or the air, and a few are designed to attack either surface or air targets (such as the ADATS missile). Most weapons require some modification in order to be launched from the air or surface, such as adding boosters to the surface-launched version.

Surface-to-Surface/Air-to-Surface

Main articles: Surface-to-surface missile and Air-to-surface missile

Ballistic

An R-36 ballistic missile launch at a Soviet silo

Ballistic missile

After the boost-stage, ballistic missiles follow a trajectory mainly determined by ballistics. The guidance is for relatively small deviations from that.
Ballistic missiles are largely used for land attack missions. Although normally associated with nuclear weapons, some conventionally armed ballistic missiles are in service, such as ATACMS. The V2 had demonstrated that a ballistic missile could deliver a warhead to a target city with no possibility of interception, and the introduction of nuclear weapons meant it could efficiently do damage when it arrived. The accuracy of these systems was fairly poor, but post-war development by most military forces improved the basic inertial platform concept to the point where it could be used as the guidance system on ICBMs flying thousands of kilometers. Today the ballistic missile represents the only strategic deterrent in most military forces, however some ballistic missiles are being adapted for conventional roles, such as the Russian Iskander or the Chinese DF-21D anti-ship ballistic missile. Ballistic missiles are primarily surface launched from mobile launchers, silos, ships or submarines, with air launch being theoretically possible with a weapon such as the cancelled Skybolt missile.
The Russian Topol M (SS-27 Sickle B) is the fastest (7,320 m/s) missile currently in service^[2]

Cruise missile

United States Tomahawk cruise missile

 Cruise missile

 

The V1 had been successfully intercepted during World War II, but this did not make the cruise missile concept entirely useless. After the war, the US deployed a small number of nuclear-armed cruise missiles in Germany, but these were considered to be of limited usefulness. Continued research into much longer ranged and faster versions led to the US's SM-64 Navaho, and its Soviet counterparts, the Burya and Buran cruise missile. However, these were rendered largely obsolete by the ICBM, and none were used operationally. Shorter-range developments have become widely used as highly accurate attack systems, such as the US Tomahawk missile, the Russian Kh-55 the German Taurus missile and the Pakistani Babur cruise missile.The BrahMos cruise missile which is a joint venture between India and Russia. The Brahmos is different in this class as it's a supersonic cruise missile which can travel much faster(2-3m) than other cruise missile which are subsonic.

Cruise missiles are generally associated with land attack operations, but also have an important role as anti-shipping weapons. They are primarily launched from air, sea or submarine platforms in both roles, although land based launchers also exist.

Anti-ship

The French Exocet missile in flight

 Anti-ship missile

 Another major German missile development project was the anti-shipping class (such as the Fritz X and Henschel Hs 293), intended to stop any attempt at a cross-channel invasion. However the British were able to render their systems useless by jamming their radios, and missiles with wire guidance were not ready by D-Day. After the war the anti-shipping class slowly developed, and became a major class in the 1960s with the introduction of the low-flying jet- or rocket-powered cruise missiles known as "sea-skimmers". These became famous during the Falklands War when an Argentine Exocet missile sank a Royal Navy destroyer.

A number of anti-submarine missiles also exist; these generally use the missile in order to deliver another weapon system such as a torpedo or depth charge to the location of the submarine, at which point the other weapon will conduct the underwater phase of the mission.

Surface-to-air

Anti-aircraft

MIM-104 Patriot missile being launched

 Surface-to-air missile

By 1944 US and British air forces were sending huge air fleets over occupied Europe, increasing the pressure on the Luftwaffe day and night fighter forces. The Germans were keen to get some sort of useful ground-based anti-aircraft system into operation. Several systems were under development, but none had reached operational status before the war's end. The US Navy also started missile research to deal with the Kamikaze threat. By 1950 systems based on this early research started to reach operational service, including the US Army's Nike Ajax, the Navy's "3T's" (Talos, Terrier, Tartar), and soon followed by the Soviet S-25 Berkut and S-75 Dvina and French and British systems. Anti-aircraft weapons exist for virtually every possible launch platform, with surface-launched systems ranging from huge, self-propelled or ship-mounted launchers to man portable systems.

Anti-ballistic

Arrow missile

Main article: Anti-ballistic missile

Like most missiles, the Arrow missile, S-300, S-400, Advanced Air Defence and MIM-104 Patriot are for defense against short-range missiles and carry explosive warheads.
However, in the case of a large closing speed, a projectile without explosives is used, just a collision is sufficient to destroy the target. See Missile Defense Agency for the following systems being developed:

• Kinetic Energy Interceptor (KEI)
• Aegis Ballistic Missile Defense System (Aegis BMD) - a SM-3 missile with Lightweight Exo-Atmospheric Projectile (LEAP) Kinetic Warhead (KW)

Air-to-air

Main article: Air-to-air missile

A F-22 Raptor fires an AIM-120 AMRAAM

Soviet RS-82 rockets were successfully tested in combat at the Battle of Khalkhin Gol in 1939.

German experience in World War II demonstrated that destroying a large aircraft was quite difficult, and they had invested considerable effort into air-to-air missile systems to do this. Their Me-262's jets often carried R4M rockets, and other types of "bomber destroyer" aircraft had unguided rockets as well. In the post-war period the R4M served as the pattern for a number of similar systems, used by almost all interceptor aircraft during the 1940s and '50s. Lacking guidance systems, such rockets had to be carefully aimed at relatively close range to successfully hit the target. The US Navy and U.S. Air Force began deploying guided missiles in the early 1950s, most famous being the US Navy's AIM-9 Sidewinder and USAF's AIM-4 Falcon. These systems have continued to advance, and modern air warfare consists almost entirely of missile firing. In the Falklands War, less powerful British Harriers were able to defeat faster Argentinian opponents using AIM-9G missiles provided by the United States as the conflict began. The latest heat-seeking designs can lock onto a target from various angles, not just from behind, where the heat signature from the engines is strongest. Other types rely on radar guidance (either on-board or "painted" by the launching aircraft). Air to Air missiles also have a wide range of sizes, ranging from helicopter launched self-defense weapons with a range of a few kilometers, to long range weapons designed for interceptor aircraft such as the Vympel R-37.

Anti-satellite

Landing Gear Of An Aircraft

Landing Gear Of An Aircraft

The undercarriage or landing gear in aviation, is the structure that supports an aircraft on the ground and allows it to taxi, takeoff and land. Typically wheels are used, but skids, skis, floats or a combination of these and other elements can be deployed, depending on the surface. Landing gear usually includes wheels equipped with shock absorbers for solid ground, but some aircraft are equipped with skis for snow or floats for water, and/or skids or pontoons (helicopters).The undercarriage is a relatively heavy part of the vehicle, it can be as much as 7% of the takeoff weight, but more typically is 4-5%.Wheeled undercarriages normally come in two types: conventional or "taildragger" undercarriage, where there are two main wheels towards the front of the aircraft and a single, much smaller, wheel or skid at the rear; or tricycle undercarriage where there are two main wheels (or wheel assemblies) under the wings and a third smaller wheel in the nose. The taildragger arrangement was common during the early propeller era, as it allows more room for propeller clearance. Most modern aircraft have tricycle undercarriages. Taildraggers are considered harder to land and take off (because the arrangement is unstable, that is, a small deviation from straight-line travel is naturally amplified by the greater drag of the mainwheel which has moved farther away from the plane's centre of gravity due to the deviation), and usually require special pilot training. Sometimes a small tail wheel or skid is added to aircraft with tricycle undercarriage, in case of tail strikes during take-off. The Concorde, for instance, had a retractable tail "bumper" wheel, as delta winged aircraft need a high angle when taking off. The Boeing 727 also has a retractable tail bumper. Some aircraft with retractable conventional landing gear have a fixed tailwheel, which generates minimal drag (since most of the airflow past the tailwheel has been blanketed by the fuselage) and even improves yaw stability in some cases.

Retractable gear
To decrease drag in flight some undercarriages retract into the wings and/or fuselage with wheels flush against the surface or concealed behind doors; this is called retractable gear.If the wheels rest protruding and partially exposed to the air stream after being retracted, the system is called semi-retractable.Most retraction systems are hydraulically operated, though some are electrically operated or even manually operated. This adds weight and complexity to the design. In retractable gear systems, the compartment where the wheels are stowed are called wheel wells, which may also diminish valuable cargo or fuel space.A design for retractable landing gear was first seen in 1876 in plans for an amphibious monoplane designed by Frenchmen Alphonse Pénaud and Paul Gauchot. Aircraft with at least partially retractable landing gear did not appear until 1917, and it was not until the late 1920s and early 1930s that such aircraft became common, with Grover Loening's military aircraft designs being among the first routinely using them for the main undercarriage members, in a system later licensed and used by his friend Leroy Grumman's aviation firm. By then, aircraft performance was improved to the point where the aerodynamic advantage of a retractable undercarriage justified the added complexity, weight and interior space penalties. An alternate method of reducing the aerodynamic penalty imposed by fixed undercarriage is to attach aerodynamic fairings (often called "spats" or "pants") on the undercarriage, with only the bottoms of the wheels exposed, as with the Junkers Ju 87 Stuka.

Pilots confirming that their landing gear is down and locked refer to "three green" or "three in the green.", a reference to the electrical indicator lights from the nosewheel and the two main gears. Red lights indicate the gear is in the up-locked position; amber lights indicate that the landing gear is in transit (neither down and locked nor fully retracted).
Multiple redundancies are usually provided to prevent a single failure from failing the entire landing gear extension process. Whether electrically or hydraulically operated, the landing gear can usually be powered from multiple sources. In case the power system fails, an emergency extension system is always available. This may take the form of a manually operated crank or pump, or a mechanical free-fall mechanism which disengages the uplocks and allows the landing gear to fall due to gravity. Some high-performance aircraft may even feature a pressurized-nitrogen back-up system.

F-117

The Lockheed F-117 Nighthawk is a single-seat, twin-engine stealth ground-attack aircraft formerly operated by the United States Air Force (USAF). A product of Lockheed Skunk Works and a development of the Have Blue technology demonstrator, the F-117 was the first operational aircraft to be designed around stealth technology. The maiden flight for the type was conducted in 1981, and it achieved initial operating capability status in October 1983.The F-117 was "acknowledged" and revealed to the world in November 1988.

The F-117 was widely publicized for its role in the Persian Gulf War of 1991. It was commonly referred to as the "Stealth Fighter", although it was a strictly ground-attack aircraft. The F-117 also saw combat in Yugoslavia; during which the only aircraft of the type to be lost in combat was shot down by a surface-to-air (SAM) battery on 27 March 1999. The Air Force retired the F-117 on 22 April 2008, primarily because of the fielding of the F-22 Raptor and the impending introduction of the multirole F-35 Lightning II.Sixty-four F-117s were built, 59 of which were production versions with five demonstrators/prototypes.

The F-117 is shaped to deflect radar signals and is about the size of an F-15 Eagle. The single-seat Nighthawk is powered by two non-afterburning General Electric F404 turbofan engines, and has quadruple-redundant fly-by-wire flight controls. It is air refuelable. To lower development costs, the avionics, fly-by-wire systems, and other parts are derived from the General Dynamics F-16 Fighting Falcon, McDonnell Douglas F/A-18 Hornet and McDonnell Douglas F-15E Strike Eagle. The parts were originally described as spares on budgets for these aircraft, to keep the F-117 project secret.

The F-117 Nighthawk has a radar signature of about 0.025 m2 (0.269 sq ft).Among the penalties for stealth are lower engine power thrust, due to losses in the inlet and outlet, a very low wing aspect ratio, and a high sweep angle (50°) needed to deflect incoming radar waves to the sides. With these design considerations and no afterburner, the F-117 is limited to subsonic speeds.

The F-117A carries no radar, which lowers emissions and cross-section, and whether it carries any radar detection equipment is classified. The aircraft is equipped with sophisticated navigation and attack systems integrated into a digital avionics suite. It navigates primarily by GPS and high-accuracy inertial navigation. Missions are coordinated by an automated planning system that can automatically perform all aspects of an attack mission, including weapons release. Targets are acquired by a thermal imaging infrared system, slaved to a laser that finds the range and designates targets for laser-guided bombs. The F-117A's split internal bay can carry 5,000 lb (2,300 kg) of ordnance. Typical weapons are a pair of GBU-10, GBU-12, or GBU-27 laser-guided bombs, two BLU-109 penetration bombs, or two Joint Direct Attack Munitions (JDAMs), a GPS/INS guided stand-off bomb.

The F-117A's faceted shape (made from 2-dimensional flat surfaces) resulted from the limitations of the 1970s-era computer technology used to calculate its radar cross-section. Later supercomputers made it possible for subsequent planes like the B-2 bomber to use curved surfaces while staying stealthy, through the use of far more computational resources to do the additional calculations needed.

Human Loses against A Bot solving Rubix Cube

Everybody has seen a Rubik’s Cube solving robot. They usually do a great job at it but, although they are faster than average humans, a trained human can usually beat them in terms of speed. This new robot solves the cube not only in the most efficient way possible, but is also the fastest at doing so, as shown in the video below.

Rubix cube solving robot