It's a bounty of earthlike planets

UNIVERSAL COUSINS

NASA’s venerable planet-hunter, the Kepler spacecraft, has shaken its 1,000th planet from the sky. Eight new worlds beyond our solar system boost the number of Kepler’s confirmed planets to 1,004 (if you’re keeping count), 
including two of the most Earthlike planets discovered so far.
Those eight new worlds are each less than 2.7 times the size of Earth, 
astronomers reported at the American Astronomical Society’s annual winter meeting. But hiding in the wings, among a group of 554 newly announced planet candidates, is an even more tantalizing set of planets.
“These candidates represent the closest analogues to the Earth-sun system found to date, and this is what Kepler has been looking for. We are now closer than we have ever been to finding a twin for Earth around a star,” says Fergal Mullally, NASA’s Ames Research Center.
Kepler’s eight newly confirmed planets are all relatively small, and they all orbit stars that are smaller and cooler than the sun. Depending which calculations 
scientists use, at least three of the planets - and perhaps all eight - are in the habitable zones of their parent stars. This is the 
region where temperatures are just right for supporting liquid water on the planet’s surface.
At least two of those planets, Kepler 438-b and Kepler 442-b, are likely to be rocky, like Earth.
“We have significantly increased the number of these verified, small, habitable-zone planets from Kepler,” says Doug 
Caldwell of the SETI Institute and NASA’s Ames Research Center.
“They really make up a special 
population that is of interest for understanding the prevalence of life in the 
universe. Yesterday we had five Kepler 
exoplanets in this special hall of fame, and today we have eight in this elite club.”
The new catalogue of worlds from 
Kepler identifies an additional 554 planet candidates, bringing the mission’s total number of candidates - objects that might be exoplanets - to 4,175. Of those 554 new candidates, eight are small, less than twice the size of Earth, and in the habitable zones of their stars. (These candidates are in addition to the eight newly confirmed planets.)
And here’s the really tantalizing bit: Six of those potential planets are orbiting 
sunlike stars and represent a class of planet that Kepler hasn’t yet gotten a good look at: the real exo-Earths.
“I’m over the moon,” says Natalie 
Batalha of NASA’s Ames Research Center. “We now have a sizable bunch of small planet candidates orbiting in the habitable zone of (sunlike) stars. This is tremen-
dously good news for Kepler’s census and for the search for life beyond Earth.”
Kepler’s mission is to determine how common Earthlike planets are in the galaxy So far, astronomers’ best guesses suggest that roughly 20 percent of sunlike stars host Earth-size planets in their 
habitable zones.
Launched in 2009, the Kepler spacecraft spent four years staring at a patch of northern sky studded with 150,000 stars. It looked for periodic twinkles caused by planets marching across the faces of those stars, a journey that temporarily dims the star’s light.
Newly found planets came rolling out of Kepler’s sky like cosmic marbles shaken loose. At first, the planetary marbles were big, but as Kepler continued to shake those stars, smaller planets followed, and finally the Earth-size planets (and smaller) came rolling out.
Then Kepler was struck by a 
mechanical problem in 2013, losing two of the four reaction wheels needed to aim the craft and keep it staring fixedly at its star field. But scientists breathed new life into the spacecraft with a different 
mission, called K2.
The spacecraft now uses the force of sunlight hitting its solar panels as 
essentially a third reaction wheel and is free to look anywhere it wants. Already, scientists have found one new planet: HIP 116454b, announced in December.
One of the K2 mission’s potential 
planetary systems is stuffed with three 
super-Earth-size planets on 10-, 24-, and 44-day orbits, Andrew Vanderburg 
of the Harvard-Smithsonian Center for 
Astrophysics reported at the AAS 
meeting.
“If real, these planets are orbiting a 
relatively cool, nearby star,” Vanderburg says. “What’s special about these is that they would be orbiting a bright star, with the potential for more sophisticated 
follow-up observations.”
That so many worlds have been found in just four years with one dedicated 
instrument is heartening for astronomers who struggled for decades to find the first exoplanet orbiting a main sequence star. That planet, a large, hot, Jupiter-like gas giant called 51 Pegasi b, was discovered 20 years ago, in October 1994.
Veteran planet-hunter Debra Fischer of Yale University, says, “We now know the universe is teeming with planets,” she says. “The next step is to figure out if the universe is teeming with life.”

Indian American student discovers 51 Eridani b: Jupiter-Like Exoplanet

An international team of astronomers, including an Indian-American PhD student, has discovered a Jupiter like exoplanet outside earth's solar system just a 100 light years away.

Researchers including Rahul I. Patel, a PhD student in Physics & Astronomy Department of Stony Brook University, New York, are calling the exoplanet a "young Jupiter" because it shares many characteristics of Jupiter.

A paper outlining the full findings is published in Science. The finding could serve as a decoder ring for astronomers to understand how planets formed around the sun as it provides an opportunity to look at younger star systems in the earlier phase of development, according to a media release.

Called 51 Eridani b, the exoplanet is the 'faintest' one on record, and also shows the strongest methane signature ever detected on an alien planet, which should yield additional clues as to how the planet formed.

"We found that 51 Eridani is surrounded by warm dust that indicates the presence of an asteroid belt," said Patel.

"Finding dust around a star is like seeing a large signpost that tells us there might be a planet," he added.

"This is because the dust is usually created when lots of large asteroids collide and destroy each other, usually pushed around by a large planet - like 51 Eridani b."

Patel led NASA's Wide-field Infrared Survey Explorer (WISE) to search for any thermal glow that dust and ice grains resulting from collisions among asteroids and comets in the Solar System can produce.

His previous work identifying recycled planetary dust, known as "debris disks," around close to a hundred other star systems, puts the discovery of the exoplanet in context.
In addition to being the faintest planet ever imaged, it's also the coldest - 400 Celsius, whereas others are around 700 °C - and features the strongest atmospheric methane signal on record.

Previous Jupiter-like exoplanets have shown only faint traces of methane, far different from the heavy methane atmospheres of the gas giants in our solar system.
All of these characteristics, the researchers say, point to a planet that is very much what models suggest Jupiter was like in its infancy.

Patel and Stanimir Metchev, a Physics & Astronomy Professor at Western University in Canada and at Stony Brook University, are co-investigators on the scientific study.
They are both members of the international Gemini Planet Imager Exoplanet Survey (GPIES) team, which is dedicated to imaging and characterising exoplanets, planets discovered outside of earth's solar system.

"What makes 51 Eridani particularly interesting is that it also harbours dust and ice in the planetary system," explained Metchev.

"These are much like the dust and the ice grains produced by collisions among asteroids and comets in the Solar System."

More data from the European Space Agency's Herschel Space Observatory reveal that 51 Eridani is also surrounded by a more distant and colder cometary belt, much like the Kuiper Belt of comets beyond Neptune in the Solar System."

The two belts - the asteroid and the cometary belt around 51 Eridani - fall on either side of the newly discovered planet 51 Eridani b.

"The overall structure bears striking resemblance to our own Solar System, with Jupiter as the most massive planet orbiting between a belt of asteroids and a belt of comets," explained Metchev.

"In 51 Eridani, we are therefore seeing what the Solar System resembled at a very young age, around the time when the Earth was still forming."

via :sci-news.com

Gravitational Lensing by Spinning Black Holes

The Double Negative Gravitational Renderer (DNGR) is the computer code used to create the iconic images of black holes and wormholes for the movie Interstellar.

It is the result of a year-long collaboration between Professor Kip Thorne and Double Negative Chief Scientist Oliver James, leading a small team of developers.

DNGR uses general-relativity equations to trace beams of light as they are bent and warped by the immense gravity of a black hole. Beams can get temporarily trapped, circling the hole many times before reaching the camera. These beams’ cross sections get stretched and squashed during this process, amplifying the light in small regions, resulting in glittering patterns in the starlight; and thin accretion discs get warped into rainbows of fire that stretch over and under the black hole.

The unprecedented detail DNGR reveals has led to its use as a tool for astrophysics research, giving us new insights into gravitational lensing.

Below you will find images and movies discussed in our paper ‘Gravitational Lensing by Spinning Black Holes in Astrophysics, and in the Movie Interstellar’ which is available for free download here:

Gravitational Lensing by Spinning Black Holes in Astrophysics, and in the Movie Interstellar

Published by IoP in Classical and Quantum Gravity James O, von Tunzelmann E, Franklin P and Thorne K S 2015 Class. Quantum Grav. 32 065001

(Also of interest may be our technical paper ‘Visualizing Interstellar’s Wormhole’)

All these movies entail a black hole with spin 0.999 of maximum and a camera at radii  6.03 GM/c2 or 2.6 GM/c2, where M is the black hole’s mass, and G and c are Newton’s gravitational constant and the speed of light. The observer is moving in a circular geodesic orbit.

View of a starfield under the influence of gravitational lensing. The camera is at radius r=2.6 GM/c2

View of a starfield under the influence of gravitational lensing. The camera is at radius r=6.03 GM/c2

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View of a starfield under the influence of gravitational lensing. The camera is at radius r=6.03 GM/c2. The primary and secondary critical curves are overlaid in purple and the path of a star at polar angle 0.608 pi is overlaid in red.

For a camera at radius rc = 6.03 GM/c2: Animation showing the mapping between points on the primary critical curve in the camera’s sky and the primary caustic curve on the celestial sphere.

Physics facts to be known before watching "Interstellar"

   Editor's note: There are no spoilers in this post. In fact, we strongly advise you to read this before going to see the film.

Christopher Nolan's latest mind-trip "Interstellar" will be premiering in theaters across the country on Friday, Nov. 7. No doubt, the film is the strangest cinematic experience you will have had since Nolan's "Inception."

But unlike "Inception," the visually-gripping film "Interstellar" is based on real, scientific concepts like neutron stars, spinning black holes, and time dilation. And if you're not at least semi-familiar with these terms, you might end up feeling a little lost during the movie.

In the movie, a crew of space explorers embark on an extra-galactic journey through a wormhole. What awaits them on the other side is another solar system with a spinning black hole for a sun.

They must race against space and time to complete their mission. All this space travel can get a little confusing, but it relies on some basic physics principles. And if you understand these principles, then you'll spend less time guessing and more time enjoying.

Here's a brief guide to the five physics concepts you need to know in order to understand "Interstellar."

Artificial Gravity

Warner Bros. UK

Spaceship in 'Interstellar' film.

A big problem we, as humans, face with long-term space travel is the affects of zero gravity in space. We were born on Earth and therefore our bodies are adapted to thrive under certain gravitational conditions, but when we're in space for long period of time, our muscles degrade.

This is an issue for the travelers in "Interstellar," too.

To combat this, scientists have conceived different designs of installing artificial gravity on spaceships. One way is to rotate the spacecraft, like in the film. The rotation creates a force, called centrifugal force, that pushes objects to the outer walls of the spacecraft. This push acts similar to how gravity would, but just in an opposite direction.

You experience this same form of artificial gravity when you're driving around a tight curve and feel like you're being pushed outward, away from the central point of the curve. For a spinning spacecraft, your wall becomes the floor on which walk.

Spinning Black Holes

Interstellar Movie

Spinning black hole in "Interstellar"

At the center of every black hole is an extremely dense, massive, compact star called a neutron star. Astronomers have known for decades that certain neutron stars spin - some at a rate of thousands of times per second.

Spinning neutron stars, that are dense enough, produce spinning black holes, which astronomers have observed, albeit indirectly. What you need to know about spinning black holes is that they warp the space around them differently than stationary black holes.

This warping process is called frame dragging, and it affects the way a black hole will look and distort the space and, more importantly, the spacetime around it. The spinning black hole you see in the film is surprisingly scientifically accurate.

Wormholes

Warner Bros. UK

Wormhole in "Interstellar" film

Wormholes - like the one the "Interstellar" crew use - are one of the only physical phenomenon in the film that don't have any observational evidence to support their existence. They are purely theoretical but an incredibly handy plot device for any science fiction story looking to traverse cosmic distances.

This is because wormholes are essentially shortcuts through space. Any object with mass will create a divot in space, meaning space can be stretched, distorted, or even folded. A wormhole is a fold in the fabric of space (and time) that connects two, otherwise extremely distant, regions in space, which enables space explorers to travel long distances over a short period of time.

The official term for a wormhole is an Einstein-Rosen bridge because they were first theorized by Albert Einstein and his colleague Nathan Rosen in 1935.

Gravitational Time Dilation

CBM Trailers

Shot of Earth and spaceship from "Interstellar"

Gravitational time dilation is a real phenomenon that has been observed on Earth. It occurs because time is relative, meaning time runs at different rates for different reference frames. When you're in a strong gravitational environment time runs slower for you relative to people in a weak gravitational environment.

If you are near a black hole, like the one in the film, your gravitational reference frame, and therefore your perception of time, is different than someone standing on Earth. This is because the gravitational pull from the black hole is stronger the closer you are to it.

For you, a minute near a black hole will still last 60 seconds, but if you could look at a clock on Earth, a minute will appear to last less than 60 seconds. This means you will age more slowly than the people on Earth. And the stronger the gravitational field you're in, the more extreme the time dilation.

This plays an important role in the film when the explorers encounter a black hole at the center of another solar system.

Five-Dimensional Reality

MovieClipsTrailers

Shot from the film "Interstellar"

Albert Einstein spent the last 30 years of his life working out what physicists call a unified theory - which would combine the mathematical concept of gravity with the other three fundamental forces of nature: the strong force, weak force, and electromagnetic force. He failed to find one, as have countless physicists since Einstein.

Gravity refuses to cooperate, and some physicists think that one way to solve this outstanding mystery is to treat our universe as if it actually functioned in five dimensions, instead of the four-dimensional universe Einstein developed in his theory of relativity, which couples three-dimensional space with one-dimensional time, a.k.a. spacetime.

Nolan toys with this idea that our universe has five dimensions in the film and gravity's important role in it all.

Movie Time

That wasn't too bad, right? Now it's time to test what you've learned and go see the movie. Let us know in the comments below if this post was helpful.

Here's the official movie trailer by Warner Bros. UK.

Little Big Black Hole

Astronomers have discovered the smallest supermassive black hole lurking in the center of a dwarf galaxy around 340 million light-years away. Small it may be, but it could help to unlock some pretty hefty black hole mysteries.

NEWS: Baby Universe Spawned Weirdly Monstrous Black Hole

The black hole was discovered in the dwarf galaxy RGG 118. It's the smallest supermassive black hole discovered to date, but it still “weighs in” at a whopping 50,000 times the mass of our sun. However, it is less than half the mass of the next-smallest supermassive black hole discovered to date and 100 times less massive than the supermassive black hole that lives in the center of our galaxy.

As we’re comparing, RGG 118′s black hole is 200,000 less massive than the biggest supermassive black hole known to exist.

Size comparisons to one side, this latest black hole discovery is extremely important to astronomers trying to understand the perplexing evolutionary processes that dominate supermassive black holes, which are known to reside in the majority of galaxies, and how they relate to their host galaxy’s evolution.

ANALYSIS: Star ‘Mass Grave’ Surrounds Our Galaxy’s Black Hole

“It might sound contradictory, but finding such a small, large black hole is very important,” said Vivienne Baldassare of the University of Michigan in Ann Arbor, in a NASA news release. “We can use observations of the lightest supermassive black holes to better understand how black holes of different sizes grow.”

RGG 118 was originally discovered by the Sloan Digital Sky Survey. Baldassare’s team used NASA’s Chandra X-ray Observatory and the 6.5-meter Clay Telescope in Chile to characterize the surprisingly small supermassive black hole. They were able to study the motion of cool gas in the center of RGG 118 in optical light using the Clay Telescope. They also zoomed in on the X-ray emissions from the hot, swirling gas in close proximity to the black hole using Chandra. Both of these measurements proved that RGG 118′s black hole acts in a similar way to other supermassive black holes in the centers of other galaxies.

The velocities of stars surrounding the black hole in the core of the galaxy also supported this finding.

A Sloan Digital Sky Survey image of RGG 118, a galaxy containing the smallest supermassive black hole ever detected. The inset is a Chandra image showing hot gas around the black hole.

NASA/CXC/UNIV OF MICHIGAN/V.F.BALDASSARE, ET AL; OPTICAL: SDSS

“We found this little supermassive black hole behaves very much like its bigger, and in some cases much bigger, cousins,” added co-author Amy Reines of the University of Michigan. “This tells us black holes grow in a similar way no matter what their size.”

One of the biggest mysteries in modern astrophysics is the existence of seriously massive, billion-solar mass supermassive black holes that must have existed in the universe less than a billion years after the Big Bang. Astronomers hope that through the discovery of this smaller example that black hole evolution models may be refined.

NEWS: Plus-Sized Black Hole Busting Out of Skinny Galaxy

Currently, it is theorized that supermassive black holes are either seeded by the rapid collapse of vast gas clouds with masses of up to 100,000 times that of our sun or they are formed by the collapse of massive stars. Now we have the opportunity to see which model is more likely in the case of RGG 118.

“We have two main ideas for how these supermassive black holes are born,” said Elena Gallo, also of the University of Michigan. “This black hole in RGG 118 is serving as a proxy for those in the very early universe and ultimately may help us decide which of the two is right.”

is it a comet????...or.....a planet!

Gliese 436 b

Extrasolar planet		List of extrasolar planets
Size comparison of Gliese 436 b with Neptune
Parent star
Star		Gliese 436
Constellation		Leo
Right ascension	(α)	11h 42m 11.0941s[1]
Declination	(δ)	+26° 42′ 23.652″[1]
Apparent magnitude	(mV)	10.68
Distance		33.4 ± 0.8 ly (10.2 ± 0.2 pc)
Spectral type		M2.5 V[1]
Mass	(m)	0.41 ± 0.05 M☉
Radius	(r)	0.42 R☉
Temperature	(T)	3318 K
Metallicity	[Fe/H]	-0.32
Age		7.41–11.05[2] Gyr
Orbital elements
Semimajor axis	(a)	0.0291±0.0004[3] AU (4.35 Gm)
		2.85 mas
Periastron	(q)	0.0247 AU (3.70 Gm)
Apastron	(Q)	0.0335 AU (5.01 Gm)
Eccentricity	(e)	0.150±0.012[3]
Orbital period	(P)	2.643904±0.000005[4] d (0.00723849 y)
		(63.4537 h)
Inclination	(i)	85.8+0.21 −0.25[4]°
Argument of periastron	(ω)	351±1.2°
Time of periastron	(T0)	2,451,551.716 ±0.01 JD
Semi-amplitude	(K)	18.68±0.8 m/s
Physical characteristics
Mass	(m)	22.2±1.0[3] M⊕
Radius	(r)	4.327±0.183[3][5] R⊕
Stellar flux	(F⊙)	29.5 ⊕
Density	(ρ)	1.51 g cm−3
Surface gravity	(g)	1.18 g
Temperature	(T)	712±36[3]
Discovery information
Discovery date		August 31, 2004
Discoverer(s)		Butler, Vogt, Marcy et al.
Discovery method		Radial velocity, Transit
Discovery site		California, USA
Discovery status		Published
Other designations
Ross 905 b, GJ 436 b,[6] LTT 13213 b, GCTP 2704.10 b, LHS 310, AC+27:28217 b, Vyssotsky 616 b, HIP 57087 b, GEN# +9.80120068 b, LP 319-75 b, G 121-7 b, LSPM J1142+2642 b, 1RXS J114211.9+264328 b, ASCC 683818 b, G 147-68 b, UCAC2 41198281 b, BPS BS 15625-0002 b, G 120-68 b, 2MASSJ11421096+2642251 b, USNO-B1.0 1167-00204205 b, CSI+27-11394 b, MCC 616 b, VVO 171 b, CSI+27-11395 b, HIC 57087 b, NLTT 28288 b, Zkh 164 b, CSI+26-11395 b, [RHG95] 1830 b, GCRV 7104 b, LFT 838 b, PM 11395+2700 b

Discovered in August 2004, Gliese 436b orbits a red-dwarf star located in the constellation Leo, around 33.4 light-years away and has a very 

The planet has an orbital period of just 2.6 Earth days and a mass approximately 23 times that of our home planet. It is categorized as a warm Neptune because it is much closer to its star (just about 4 million km away) than frigid Neptune is to the Sun.

Gliese 436b has an atmosphere leaves behind a gigantic trail of hydrogen, which is about 50 times the size of the parent star, Gliese 436. A phenomenon this large has never before been seen around such a small planet.

“What we can see is a large cloud of hydrogen gas absorbing the light from a red dwarf star as its exoplanet, Gliese 436b, passes in front. The cloud is created as of result of X-rays emitted from the red dwarf burning off Gliese 436 b 's upper atmosphere,” explained Dr Peter Wheatley of the University of Warwick, UK, a co-author on the study published in the journal Nature.

“The cloud forms a comet-like tail as a result of UV light coming from the star pushing on the hydrogen and causing it to spiral outwards.

Because the atmosphere of our planet blocks most UV light, the team needed a space telescope with Hubble’s UV capability and exquisite precision to find the Gliese 436b’s comet-like tail.

“You would have to have Hubble’s eyes. You would not see it in visible wavelengths. But when you turn the UV eye of Hubble onto the system, it’s really kind of a transformation, because the planet turns into a monstrous thing,” said study lead author Dr David Ehrenreich from the Observatory of the University of Geneva in Switzerland.

He added: “this cloud of hydrogen is very spectacular. Although the evaporation rate doesn’t threaten the planet right now, we know that the star was more active in the past. This means that the planet’s atmosphere evaporated faster during its first billion years of existence. Overall, we estimate that it may have lost up to 10 percent of its atmosphere.”

“Around 1,000 metric tons of hydrogen are being burnt off from Gliese 436b’s atmosphere every second; which equates to only 0.1 percent of its total mass every billion years,” Dr Wheatley said.

The same process may explain the disappearance of atmospheres observed on terrestrial exoplanets, which rotate very close to their star and are extremely hot, such as the so-called super-Earths.

“Finding the cloud around Gliese 436b could be a game-changer for characterizing atmospheres of the whole population of Neptunes and super-Earths in UV observations,” said co-author Dr Vincent Bourrier, also from the Observatory of the University of Geneva.

The astronomers suggest that evaporation such as this may also have happened in the earlier history of the Solar System, when the Earth had a hydrogen-rich atmosphere that dissipated.

It is also possible that it could happen to Earth’s atmosphere at the end of our planet’s life, when the Sun swells up to become a red giant and boils off our remaining atmosphere, before engulfing our planet completely.

Gliese 436 b /ˈɡliːzə/ (sometimes called GJ 436 b^[7]) is a Neptune-sized exoplanet orbiting the red dwarf Gliese 436.^[8] It was the first hot Neptune discovered with certainty (in 2007) and was among the smallest known transiting planets in mass and radius until the much smaller Kepler exoplanet discoveries started coming in by 2010.

In December 2013, NASA reported that clouds may have been detected in the atmosphere of GJ 436 b.^{[9][10][11][12]}

Contents

  [hide] 

• 1 Discovery
• 2 Physical characteristics
• 3 Orbital characteristics
• 4 See also
• 5 References
• 6 Selected media articles
• 7 External links

Discovery[edit]

The radial velocity trend of Gliese 436, caused by the presence of Gliese 436 b

Gliese 436 b was discovered in August 2004 by R. Paul Butler and Geoffrey Marcy of the Carnegie Institute of Washington and University of California, Berkeley, respectively, using the radial velocity method. Together with 55 Cancri e, it was then the first of a new class of planets with a minimum mass (M sini) similar to Neptune.

The planet was recorded to transit its star by an automatic process at NMSU on January 11, 2005, but this event went unheeded at the time.^[13] In 2007, Gillon led a team which observed the transit, grazing the stellar disc relative to Earth. Transit observations led to the determination of Gliese 436 b's exact mass and radius, both of which are very similar to Neptune. Gliese 436 b then became the smallest known transiting extrasolar planet. The planet is about 4000 km larger in diameter than Uranus and 5000 km larger than Neptune and a bit more massive. Gliese 436b (also known as GJ 436b) orbits its star at a distance of 4,000,000 km or 15 times closer than Mercury's average distance from the Sun.

Physical characteristics[edit]

Possible interior structure of Gliese 436 b

The planet's surface temperature is estimated from measurements taken as it passes behind the star to be 712 K (439 °C).^[3] This temperature is significantly higher than would be expected if the planet were only heated by radiation from its star (which had been, in a Reuters article from a month prior to this measurement, estimated at 520 K). Whatever energy that tidal effects deliver to the planet does not notably affect its temperature.^[14] Its discoverers allowed for a temperature increase due to a greenhouse effect.^[15]

Its main constituent was initially predicted to be hot "ice" in various exotic high-pressure forms,^[15][16] which remains solid because of the planet's gravity despite the high temperatures.^[17] The planet could have formed further from its current position, as a gas giant, and migrated inwards with the other gas giants. As it arrived in range, the star would have blown off the planet's hydrogen layer via coronal mass ejection.^[18]

However when the radius became better known, ice alone was not enough to account for it. An outer layer of hydrogenand helium up to ten percent in mass would be needed on top of the ice to account for the observed planetary radius.^[3][4] This obviates the need for an ice core. Alternatively, the planet may be a super-earth.^[19]

Observations of the planet's brightness temperature with the Spitzer Space Telescope suggest a possible thermochemical disequilibrium in the atmosphere of this exoplanet. Results published in Nature suggest that Gliese 436b's dayside atmosphere is abundant in CO and deficient in methane (CH₄) by a factor of ~7,000. This result is unexpected because, based on current models at this temperature, the atmospheric carbon should prefer CH₄ over CO.^{[20][21][22][23]}

Formation of a helium atmosphere on ahelium planet, possibly like Gliese 436 b.

In June 2015, scientists reported that the atmosphere of Gliese 436 b was evaporating, resulting in a giant cloud around the planet and, due to radiation from the host star, a long trailing tail 14×10⁶ km (9×10⁶ mi) long.^[24]

Artist impression of Gliese 436b shows the enormous comet-like cloud of hydrogen bleeding off.^[25]

Orbital characteristics[edit]

One orbit around the star takes only about 2 days, 15.5 hours. Gliese 436 b's orbit is likely misaligned with its star's rotation.^[22]

The eccentricity of Gliese 436 b's orbit is inconsistent with models of planetary system evolution. To have maintained its eccentricity over time requires that it be accompanied by another planet.^[3][26]

See also[edit]