Exoplanets

The term ‘exoplanet’ applies to any planet outside
of our solar system. At last count, we have
identified 3,538.
Out of the thousands of planets we know about,
some of them are incredibly bizarre compared to
what we are used to seeing in our own solar
system. Here are some exoplanets with very
unique characteristics:
Kepler-78b
The most astounding fact about Kepler-78b is
that it shouldn’t even exist, according to our
current knowledge of planetary formation. It is
extremely close to its star at only 550,000 miles
(900,000 kilometers). As a comparison, Mercury
only gets within 28.5 million miles (45.9 million
kilometers) of the sun in the nearest point of
orbit. With that proximity, it isn’t clear how the
planet could have formed as the star was much
larger when the planet formed. With its current
distance, that would mean it formed inside the
star, which is impossible as far as we know.
The planet itself is only slightly larger than Earth,
though surface conditions are markedly different.
The temperature on the surface is estimated to be
4300° F (2400° C), which is nearly nine times as
hot as the temperature on Venus. Unfortunately
for Kepler-78b, it is likely that the star’s
gravitational pull will gradually bring the star
closer and totally consume it in the next 3 billion
years.
WASP-12b
While Kepler-78b still has about 3 billion more
years before getting consumed by its star, the
process is well underway for WASP-12b . This
exoplanet is actively getting pulled apart by its
parent star, much to the delight of astronomers
who can watch the process unfold. So much
material has been pulled away from the planet, it
has been pulled into an oblong football shape.
Astronomers have estimated that WASP-12b has
about 10 million more years until it is completely
pulled apart by the star.
The planet is described as a “hot Jupiter” as it is
a gas planet that is about 40 percent larger than
Jupiter. It is currently so close to its star that it
only takes 1.1 Earth days for the planet to
complete a full orbit. The star, WASP-12, is G-
type main sequence star, just like our own sun. It
is located about 800 lightyears away in the Auriga
constellation.
TrES-2b
TrES-2b has been dubbed the “dark planet”
because it does not reflect light. If we were able
to view it directly, it would likely just look like a
coal-black ball of gas. At 1800°F (1000°C) the
planet is way too hot for clouds, which would
help reflect the star’s light. The red tinges are
areas of superheated gas. Other darker planets
only reflect about 10% of the star’s light, but
TrES-2b only reflects about 1%, making it the
darkest planet ever discovered.
Why is TrES-2b so dark? Scientists aren’t quite
sure. Right now, the best guess is that the
majority of the planet’s composition is something
like sodium or potassium which absorbs light.
This dark world is located about 750 lightyears
away in the Draco constellation.
HD 189773b
HD 189773b is pretty exciting. It is relatively
close, at only 63 lightyears away. It is also the
first planet to have its color determined and it
turned out to be a pretty blue planet, just like
Earth. Unlike Earth, however, HD 189773b is a
gas giant with a temperature that reaches a
sweltering 1800°F (1000°C). The weather gets
more extreme, because intense pressure and
temperature turns silicate particles in the
atmosphere into glass, which then rains down. As
if that doesn’t sound dangerous enough, the
winds have been estimated to gust at 4,000 mph
(7,000 km/h) which really whips those glass
particles around.
55 Cancri e
55 Cancri e is twice the size of Earth but is nearly
8 times more massive and twice as dense. Last
fall, researchers deduced that the mass of the
planet was largely carbon. Due to the pressure
and surface temperature of 4892°F (2700°C) it
very well could have formed diamond. It is so
close to its parent star it takes a mere 18 hours
for the planet to complete a full orbit.
55 Cancri e is only about 40 light-years away
from us in the Cancer constellation. The parent
star is much more carbon than our own sun, so it
might be too surprising that planet e is also
carbon-rich. From there, it isn’t much of a stretch
to assume that the other four known planets in
the system would also have a high carbon
content.
Because of these extreme conditions, astronomers
don’t believe that 55 Cancri e has an atmosphere,
making it a poor candidate for the possibility for
life. However, it is close enough for astronomers
to use it to test hypotheses about planetary
formation.
PSR B1620-26b
Nicknamed “Methuselah,” PSR B1620-26b is the
oldest known exoplanet. The planetary system
formed approximately 12.7 billion years ago, when
the Milky Way galaxy was in its infancy. It is
located in the Scorpius constellation about 12,400
lightyears away.
Methuselah orbits binary stars and goes around
them in a circumbinary orbit. As if Methuselah’s
age isn’t interesting enough, the fact that it orbits
two mismatched dead stars is quite unusual. One
of the stars is a pulsar and the other is a white
dwarf. Since Methuselah is found in a dense star
cluster, astronomers initially thought it could be a
star as well, and would be considered a brown
dwarf. Measurements from the Hubble would
confirm that Methuselah is a planet, and it
remains the oldest one we’ve ever discovered.
TrES-4
Located 1,400 lightyears away in the Hercules
constellation, TrES-4 is the largest exoplanet we
have discovered so far. Though it is over 1.7
times the size of Jupiter, it has an extremely low
density and is categorized as a “puffy” planet.
The planet’s density is about the same as cork,
which came as quite a shock. Astronomers
attribute this to extreme heat of 2,300° F (1,260°
C) due to is proximity to the star. At only 4.5
million miles (7.2 million kilometers) away from
its sun, TrES-4 is able to complete an orbit in
three Earth days.
Gliese 436 b
30 lightyears away in the constellation Leo, Gliese
436 b is a planet that is about as massive as
Neptune. The planet also happens to be covered
in burning ice - though the ice isn’t anything like
what we’re used to. The extreme pressure of the
planet forces the water to stay in solid form, even
though the temperature exceeds 570° F (300° C).
The outer layer of the solid water is superheated
and comes off as vapor. Water has over 10 solid
states, not including common ice.
In its present position, the water would not have
been able to condense down into a solid,
indicating that it migrated toward its sun after it
formed.

Cryogenic Rocket Engines

A cryogenic rocket engine is a rocket engine that uses a cryogenic fuel or oxidizer, that is, its fuel or oxidizer (or both) are gases liquefied and stored at very low temperatures. Notably, these engines were one of the main factors of the ultimate success in reaching the Moon by the Saturn Vrocket.

During World War II, when powerful rocket engines were first considered by the German, American and Soviet engineers independently, all discovered that rocket engines need high mass flow rate of both oxidizer and fuel to generate a sufficient thrust. At that time oxygen and low molecular weight hydrocarbons were used as oxidizer and fuel pair. At room temperature and pressure, both are in gaseous state. Hypothetically, if propellants had been stored as pressurized gases, the size and mass of fuel tanks themselves would severely decrease rocket efficiency. Therefore, to get the required mass flow rate, the only option was to cool the propellants down to cryogenic temperatures (below −150 °C, −238 °F), converting them to liquid form. Hence, all cryogenic rocket engines are also, by definition, either liquid-propellant rocket engines or hybrid rocket engines.

Various cryogenic fuel-oxidizer combinations have been tried, but the combination of liquid hydrogen (LH2) fuel and the liquid oxygen (LOX) oxidizer is one of the most widely used. Both components are easily and cheaply available, and when burned have one of the highest entropy releases by combustion,[4] producing specific impulse up to 450 s (effective exhaust velocity 4.4 km/s).

Construction

The major components of a cryogenic rocket engine are the combustion chamber (thrust chamber), pyrotechnic igniter, fuel injector, fuel cryopumps, oxidizer cryopumps, gas turbine, cryo valves, regulators, the fuel tanks, and rocket engine nozzle. In terms of feeding propellants to combustion chamber, cryogenic rocket engines (or, generally, all liquid-propellant engines) work in either an expander cycle, a gas-generator cycle, a staged combustion cycle, or the simplest pressure-fed cycle.
The cryopumps are always turbo pumps powered by a flow of fuel through gas turbines. Looking at this aspect, engines can be differentiated into a main flow or a bypass flow configuration. In the main flow design, all the pumped fuel is fed through the gas turbines, and in the end injected to the combustion chamber. In the bypass configuration, the fuel flow is split; the main part goes directly to the combustion chamber to generate thrust, while only a small amount of the fuel goes to the turbine.

MARS ORBITORS MISSION's Eyes

MOM's Eyes !
The spectacular image of Earth posted a couple of days ago, which has become one of our most
popular post so far, was clicked by this compact instrument called Mars Color Camera (MCC).
MCC captures RGB images and information about the features and composition of the Martian
surface. MCC images will be useful to monitor the dynamic events and also the weather on Mars. It
will also be used for probing the two moons of Mars – Phobos & Deimos. It also provides the
context information for other science payloads on-board ISRO's Mars Orbiter Mission spacecraft.

Aircraft Carriers Of India

Aircraft carriers of India!
India currently owns 4 aircraft carriers out of which
2 are in service.
INS Vikrant R11 : Purchased from the United Kingdom in 1957, upon completion in 1961 it was commissioned as the first aircraft carrier of the Indian Navy. After a distinguished service, she was decommissioned in January 1997. She was laid down in 1943 and launched in 1945. Her name before being sold to India was HMS Hercules.
Displacement : 15700 tons standard. 19,500 tons full load.
Aircraft : It could carry approximately 20 aircraft -
a combination of helicopters and fixed wing aircraft
such as :
Westland Sea King
HAL Chetak
Sea Harrier
Breguet Alizé Br.1050
& Hawker Sea Hawk.
INS Viraat : Purchased from the United Kingdom in
1987, upon completion in 1959 she was
commissioned as the Royal Navy's HMS Hermes
and was transferred to India in 1987. She has
under gone many refits and is still in service. She
was launched in 1953.
Displacement : 23,900 tons standard. 28,700 tons
full load.
Aircraft : It is a STOVL type aircraft carrier and can
carry 30 aircraft - a combination of helicopters and
fixed wing aircraft such as :
Westland Sea King.
Sea Harrier.
HAL Dhruv.
HAL Chetak.
INS Vikramaditya : Purchased by India in 2004, the
ship completed her sea trials in July 2013 and her
aviation trials in September 2013. She was formally
commissioned into the Indian Navy on 16
November 2013 at a ceremony held at
Severodvinsk, Russia. Before being commissioned,
the ship underwent a major refit and modifications.
These upgrade plans involve stripping all the
weaponry and missile launcher tubes from the
ship's foredeck to make way for a STOBAR
configuration. This converted the Gorshkov from a
hybrid carrier/cruiser to a pure carrier. She was
originally commissioned in 1987 but was
decommissioned in 1996 as she was too expensive
to operate by Russia in a post Cold War budget.
Her previous named were Baku and Admiral
Gorshkov. Before being decommisioned in 1996 she
was used as a helicopter carrier which probably
was also used as STOVL carrier for Russia's VTOL
aircraft.
Displacement : 45400 tons loaded.
Aircraft : it is a STOBAR type of aircraft carrier and
can carry a total of 34 aircraft - a combination of
helicopters and fixed wing aircraft such as :
MiG-29K.
Kamov Ka-28.
Kamov ka-31.
HAL Dhruv.
INS Vikrant 2/IAC-1 : India's first indigenous
aircraft carrier. Laid down in 2009, she was
launched on 12th August 2013 and is expected to
be commissioned in 2017-2018. She is part of the
Vikrant-class aircraft carriers. When commissioned,
she will serve as the 4th aircraft carrier of India.
Displacement : When the aircraft carrier was
launched, it weighed 37500 tons. When completed,
the aircraft carrier will weigh 40000 to 45000 tons.
Aircraft : It is a STOBAR type aircraft carrier and
may carry up to 40 aircraft - a combination of
helicopters and fixed wing aircraft such as :
MiG-29K.
HAL Tejas MK2 Naval variant.
HAL Dhruv.
Kamov Ka-31/Westland Sea King.
And possibly future aircraft of Indian Navy Air Arm.
Planned/proposed aircraft carriers of the past and
present of Indian navy.
INS Vikram (R-13) : Laid down as HMS Leviathan
(R97) of the Royal Navy on 18 October 1943 and
launched on 7 June 1945, the ship was never
completed. Laid down for future use, she would
have been bought by India had some budgetary
problems not come in the way. She was scrapped
incomplete in 1968. If completed, she would have
looked like the INS Vikrant (R11).
INS Vishal/IAC-2 : It is planned aircraft carrier
which will be part of the same class as INS Vikrant
2. Design stage for INS Vishal (IAC-II) has begun,
which is being undertaken by the navy’s 'Naval
Design Bureau'. The navy has decided not to seek
outside help in preparing the design concept and
implementation plans. The navy might later seek
help from the Russian Design Bureau in order to
integrate the Russian aircraft onto Vishal.
Displacement : It is planned to weigh in at 65000
tons loaded.
Aircraft : It is to be a CATOBAR type aircraft carrier
and may carry more than 40 aircraft. Naval
versions of Tejas, Sukhoi/HAL FGFA, Advanced
Medium Combat Aircraft (AMCA) and the Rafale M
fighter jets are likely to operate from the aircraft
carrier, helicopters as well will be operated from the
carrier. EMALS may be used for it's catapult.
---------------------------------------------
----------------------
Key :
STOVL : Short Take Off Vertical Landing.
STOBAR : Short Take Off But Arrested Landing.
CATOBAR : CAtapult Take Off But Arrested landing.
IAC : Indigenous Aircraft Carrier.
EMALS : Electromagnetic Aircraft Launch System.

Box Wing Aircraft

Box Wings- Return of Biplane era?
A box wing aircraft uses two sets of wings, one forward pair configured normally, and a second set
positioned where the tail would normally be and sweeping forward to merge with the first set of
wings, forming a complete 'loop' of lifting surface.In the early years of aviation, biplanes dominated
the skies, and with good reason. The two layers of wings created a stronger airframe, and the
increased wing surface area provided more lift,which well suited the modestly-powered engines of

the time.
The concept has been updated for the twenty first century, with the aim of increasing fuel efficiency,
reducing pollution and noise, and ultimately, saving money. Lockheed Martin proposed this design for
Leaner, greener flying machines for the year 2025 initiative, under contract to the NASA Aeronautics
Research Mission Directorate's Environmentally Responsible Aviation Project.
The biggest advantage of this configuration is the increased lift created by using two sets of wings.
The design being pursued by Lockheed Martin would increase the lift to drag ratio by 16%,
allowing the craft to use less fuel and therefore could fly the same routes as conventional aircraft
for less money. The savings on fuel could also allow it to stay in the air longer or to fly farther for
the same size fuel tank. The increased wing area would also allow it to make steeper descents and
ascents safely than current conventional jet liners. The swept-back design of the double looped wing
would also allow the aircraft to readily handle transonic and supersonic speeds.
Lockheed Martin's design also incorporates ultrahigh-bypass turbofan engines and advanced
lightweight composite materials, which combined with its box wing configuration, promises to make
the aircraft up to 50% more fuel efficient than contemporary jetliners. Similar cost and fuel-saving
innovations are being combined with box wing designs by Bauhaus Luftfahrt, with the ultimate
goal of creating aircraft that not only operate more cheaply, but are more environment-friendly.
The US Air Force has also looked into box wing designs. Though details of their actual progress are
sketchy online, it is likely the box wing's greater lift-to-drag ratio, fuel efficiency, and greater
endurance in the air is what is attracting the armed forces to such aircraft, especially for the large
airborne tanker craft used to refuel military jets in flight.

Monday: NASA's public MAVEN events inWashington, Maryland, Mississippi, Alabama, WestVirginia.

Five NASA centers around the United States will host events and activities Monday, Nov. 18, for the public to view the launch of the agency's Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft and learn about its mission. MAVEN, which is set to launch at 1:28 p.m. EST
from Cape Canaveral Air Force Station in Florida, will take critical measurements of the Martian upper atmosphere to help scientists understand climate change over the Red Planet's history. Here is a schedule of events at NASA facilities in
Washington, Maryland, Mississippi, Alabama and
West Virginia:
(All times Eastern)
11 a.m. -- NASA's Stennis Space Center, near Bay St. Louis, Miss.: The INFINITY Science Center
located on I-10 Exit 2, will host a live viewing of the launch, science project discussions with
featured speakers, conduct a parachute design and launch demonstration and a Mars habitat
competition. Visitors also may have their photographs taken on a simulated Martian surface.
For more information, call 228-533-9025, ext. 311.
Noon -- NASA Headquarters, Washington: Launch coverage will be available in the James Webb
Auditorium at 300 E St. SW. Jim Garvin, chief scientist at NASA’s Goddard Space Flight Center in Greenbelt Md., will discuss Mars exploration plans and answer questions from the public. MAVEN materials and other handouts will be available. Noon -- NASA's Marshall Space Flight Center in Huntsville, Ala. and the U.S. Space & Rocket Center will host a pre-launch panel discussion with representatives from the Marshall Center titled "Deep Space Exploration: Mars and Beyond." There
will also be educational activities for children. The event will be held in the U.S. Space & Rocket Center's Davidson Center Digital Theater located at One Tranquility Base, Huntsville, Ala., 35805. The event is open to the public and there will be signs directing the public where to park. The launch will be shown live in the theater at 1:28 p.m. For more information, contact Shannon Ridinger at
256-544-3774.
1 p.m. -- NASA's Goddard Space Flight Center,
Greenbelt, Md.: Goddard's Visitors Center auditorium located off ICESat Road (formerly Soil Conservation Road) will show the launch and have available a planetary scientist to answer visitors'
questions. For more information, contact the Goddard newsroom at 301-286-8955.
1 p.m. -- NASA’s Independent Verification and Validation (IV&V) Facility, 5000 NASA Blvd. 5th Floor, Fairmont, W.Va: Events will include educational activities for students and educators before and after launch coverage. Take either elevator to the 5th floor. Media should use the
South entrance. For more information contact Jennifer Neptune at: 304-367-8262.
- courtesy of NASA

NASA'S Mars mission rocket arrives at launching pad

The US space agency NASA Saturday rolled out to the launching pad at Cap Canaveral, Florida, the Atlas 5 rocket, which will blast off Monday for Mars carrying the MAVEN spacecraft, which will study the atmosphere of that planet.

The rocket, 57.3 metres long, is scheduled to take off from Florida Monday at 1:28 p.m. 

Meteorologists point to a 60 percent probability of favourable weather conditions for the rocket launch on that day and hour.

The Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft will travel 10 months through space to an orbit around the red planet, and will then collect data to determine how and why it became the cold desert it is today.

Research up to now has shown that Mars was once a planet with water but the influence of the sun and other factors caused it to lose its atmosphere.