May 14, 2016

Africa and Europe seen by DSCOVR Observatory

Africa and Europe seen by DSCOVR Observatory

Africa is front and center in this image of Earth taken by a NASA camera on the Deep Space Climate Observatory (DSCOVR) satellite. The image, taken July 6 from a vantage point one million miles from Earth, was one of the first taken by NASA’s Earth Polychromatic Imaging Camera (EPIC).

Central Europe is toward the top of the image with the Sahara Desert to the south, showing the Nile River flowing to the Mediterranean Sea through Egypt. The photographic-quality color image was generated by combining three separate images of the entire Earth taken a few minutes apart. The camera takes a series of 10 images using different narrowband filters -- from ultraviolet to near infrared -- to produce a variety of science products. The red, green and blue channel images are used in these Earth images.

The DSCOVR mission is a partnership between NASA & National Oceanic and Atmospheric Administration (NOAA) with the primary objective to maintain the nation’s real-time solar wind monitoring capabilities, which are critical to the accuracy and lead time of space weather alerts and forecasts from NOAA.

DSCOVR was launched in February to its planned orbit at the first Lagrange point or L1, about one million miles from Earth toward the sun. It’s from that unique vantage point that the EPIC instrument is acquiring images of the entire sunlit face of Earth. Data from EPIC will be used to measure ozone and aerosol levels in Earth’s atmosphere, cloud height, vegetation properties and a variety of other features.

Image Credit: NASA
Explanation from: https://www.nasa.gov/image-feature/africa-and-europe-from-a-million-miles-away

Center of the Milky Way Galaxy

Center of the Milky Way Galaxy

The spectacular composite image combines observations using infrared light and X-ray light that see through the obscuring dust and reveal the intense activity near the galactic core. Note that the center of the galaxy is located within the bright white region on the lower right-hand side of the image (annotated on the labeled image). Each telescope's contribution is presented in a different color. Yellow represents the near-infrared observations of Hubble. Red represents the infrared observations of Spitzer. Blue and violet represent the X-ray observations of Chandra.

Image Credit: X-ray: NASA/CXC/UMass/D. Wang et al.; Optical: NASA/ESA/STScI/D.Wang et al.; IR: NASA/JPL-Caltech/SSC/S.Stolovy
Explanation from: http://chandra.si.edu/photo/2009/galactic/more.html

Rainbows and Rays over Bryce Canyon

Bryce Canyon

What's happening over Bryce Canyon? Two different optical effects that were captured in one image taken in July 2015. Both effects needed to have the Sun situated directly behind the photographer. The nearest apparition was the common rainbow, created by sunlight streaming from the setting Sun over the head of the photographer, and scattering from raindrops in front of the canyon. If you look closely, even a second rainbow appears above the first. More rare, and perhaps more striking, are the rays of light that emanate out from the horizon above the canyon. These are known as anticrepuscular rays and result from sunlight streaming though breaks in the clouds, around the sky, and converging at the point 180 degrees around from the Sun. Geometrically, this antisolar point must coincide with the exact center of the rainbows. Located in Utah, USA, Bryce Canyon itself contains a picturesque array of ancient sedimentary rock spires known as hoodoos.

Image Credit & Copyright: John Rummel
Explanation from: http://apod.nasa.gov/apod/ap150728.html

May 13, 2016

The Perseus A Galaxy

Perseus A

The behemoth galaxy NGC 1275, also known as Perseus A, lies at the centre of Perseus Galaxy Cluster. By combining multi-wavelength images into this single composite, the dynamics of the galaxy become visible. Detail and structure from optical, radio and X-ray wavelengths have been combined for an aesthetically pleasing image which shows the violent events in the galaxy's heart. NGC 1275 is an active galaxy well-known for its radio source (Perseus A) and is a strong emitter of X-rays due to the presence of the supermassive black hole in its centre.

Hubble data from the Advanced Camera for Surveys covers visible-light wavelengths and is shown in the red, green and blue. Radio data from NRAO's Very Large Array at 0.91 m was also used. In this composite image, dust lanes, star-forming regions, hydrogen filaments, foreground stars, and background galaxies are contributions from the Hubble optical data. The X-ray data contributes to the soft but violet shells around the outside of the centre. The pinkish lobes toward the centre of the galaxy are from radio emission. The radio jets from the black hole fill the X-ray cavities. Chandra data from the ACIS covers X-ray wavelengths from 0.1771 to 4.133 nm (0.3-7 KeV).

Image Credit: NASA, ESA, NRAO and L. Frattare (STScI)
Explanation from: http://www.spacetelescope.org/images/heic0817b/

Perseid Meteors and the Milky Way Galaxy over Hvar Island

Perseid Meteors and the Milky Way Galaxy

Hvar Island, Croatia
August 2015

Image Credit & Copyright: Petr Horálek

Thousands of Galaxies

Thousands of Galaxies

Peering deep into the early Universe, this picturesque parallel field observation from the NASA/ESA Hubble Space Telescope reveals thousands of colourful galaxies swimming in the inky blackness of space. A few foreground stars from our own galaxy, the Milky Way, are also visible.

In October 2013 Hubble’s Wide Field Camera 3 (WFC3) and Advanced Camera for Surveys (ACS) began observing this portion of sky as part of the Frontier Fields programme. This spectacular skyscape was captured during the study of the giant galaxy cluster Abell 2744, otherwise known as Pandora’s Box. While one of Hubble’s cameras concentrated on Abell 2744, the other camera viewed this adjacent patch of sky near to the cluster.

Containing countless galaxies of various ages, shapes and sizes, this parallel field observation is nearly as deep as the Hubble Ultra-Deep Field. In addition to showcasing the stunning beauty of the deep Universe in incredible detail, this parallel field — when compared to other deep fields — will help astronomers understand how similar the Universe looks in different directions

Image Credit: NASA, ESA and the HST Frontier Fields team (STScI), Judy Schmidt
Explanation from: https://www.spacetelescope.org/images/potw1610a/

May 12, 2016

Spiral Galaxy NGC 6814

Spiral Galaxy NGC 6814

Spiral galaxies together with irregular galaxies make up approximately 60% of the galaxies in the local Universe. However, despite their prevalence, each spiral galaxy is unique — like snowflakes, no two are alike. This is demonstrated by the striking face-on spiral galaxy NGC 6814, whose luminous nucleus and spectacular sweeping arms, rippled with an intricate pattern of dark dust, are captured in this NASA/ESA Hubble Space Telescope image.

NGC 6814 has an extremely bright nucleus, a telltale sign that the galaxy is a Seyfert galaxy. These galaxies have very active centres that can emit strong bursts of radiation. The luminous heart of NGC 6814 is a highly variable source of X-ray radiation, causing scientists to suspect that it hosts a supermassive black hole with a mass about 18 million times that of the Sun.

As NGC 6814 is a very active galaxy, many regions of ionised gas are studded along its spiral arms. In these large clouds of gas, a burst of star formation has recently taken place, forging the brilliant blue stars that are visible scattered throughout the galaxy.

Image Credit: ESA/Hubble, NASA, Judy Schmidt
Explanation from: https://www.spacetelescope.org/images/potw1619a/

The star-forming region NGC 3603

star-forming region NGC 3603

The star-forming region NGC 3603 contains one of the most impressive massive young star clusters in the Milky Way. Bathed in gas and dust the cluster formed in a huge rush of star formation thought to have occurred around a million years ago. The hot blue stars at the core are responsible for carving out a huge cavity in the gas seen to the right of the star cluster in NGC 3603's centre.

Image Credit: NASA, ESA and the Hubble Heritage (STScI/AURA)

The Southern Cross

Southern Cross

Crux is a constellation located in the southern sky in a bright portion of the Milky Way, being among the most distinctive even though it is the smallest of all 88 modern constellations. Its name is Latin for cross, and it is dominated by a cross-shaped or kite-like asterism that is commonly known as the Southern Cross.

Predominating the asterism is the most southerly first-magnitude star and brightest star in the constellation, the blue-white Alpha Crucis or Acrux, followed by four other stars, descending in clockwise order by magnitude: Beta, Gamma (one of the closest red giants to Earth), Delta and Epsilon Crucis. Many of these brighter stars are members of the Scorpius–Centaurus Association, a large but loose group of hot blue-white stars that appear to share common origins and motion across the southern Milky Way. The constellation contains four Cepheid variables that are visible to the naked eye under optimum conditions. Crux also contains the bright and colourful open cluster known as the Jewel Box (NGC 4755) and, to the southwest, partly includes the extensive dark nebula, known as the Coalsack Nebula.

Image Credit & Copyright: Carlos Fairbairn
Explanation from: https://en.wikipedia.org/wiki/Crux

May 11, 2016

Mercury Solar Transit

Mercury TransitMercury Transit

The planet Mercury is seen in silhouette, lower third of image, as it transits across the face of the Sun Monday, May 9, 2016, as viewed from Boyertown, Pennsylvania. Mercury passes between Earth and the Sun only about 13 times a century, with the previous transit taking place in 2006.

Image Credit: NASA/Bill Ingalls

The Mice Galaxies

The Mice Galaxies

Located 300 million light-years away in the constellation Coma Berenices, the colliding galaxies have been nicknamed "The Mice" because of the long tails of stars and gas emanating from each galaxy. Otherwise known as NGC 4676, the pair will eventually merge into a single giant galaxy.

Image Credit: NASA, Holland Ford (JHU), the ACS Science Team and ESA
Explanation from: https://www.spacetelescope.org/images/heic0206b/

A Colorful Lunar Corona

Lunar Corona

What are those colorful rings around the Moon? A corona. Rings like this will sometimes appear when the Moon is seen through thin clouds. The effect is created by the quantum mechanical diffraction of light around individual, similarly-sized water droplets in an intervening but mostly-transparent cloud. Since light of different colors has different wavelengths, each color diffracts differently. Lunar Coronae are one of the few quantum mechanical color effects that can be easily seen with the unaided eye. The featured lunar corona was captured around a Strawberry Moon on June 2, 2015 from La Plata, Argentina. Similar coronae that form around the Sun are typically harder to see because of the Sun's great brightness.

Image Credit & Copyright: Sergio Montúfar, Planetario Ciudad de La Plata
Explanation from: http://apod.nasa.gov/apod/ap150615.html

Twin Jet Nebula

Twin Jet Nebula

M2-9 is a striking example of a 'butterfly' or a bipolar planetary nebula. Another more revealing name might be the 'Twin Jet Nebula'. If the nebula is sliced across the star, each side of it appears much like a pair of exhausts from jet engines. Indeed, because of the nebula's shape and the measured velocity of the gas, in excess of 200 miles per second (approx. 322 kilometres per second), astronomers believe that the description as a super-super-sonic jet exhaust is quite apt. Ground-based studies have shown that the nebula's size increases with time, suggesting that the stellar outburst that formed the lobes occurred just 1, 200 years ago.

Image Credit: Bruce Balick (University of Washington), Vincent Icke (Leiden University, The Netherlands), Garrelt Mellema (Stockholm University), and NASA/ESA
Explanation from: https://www.spacetelescope.org/images/opo9738a/

May 10, 2016

Mercury Transit

Mercury Transit

On May 9, 2016, Mercury passed directly between the Sun and Earth. This event – which happens about 13 times each century – is called a transit. NASA’s Solar Dynamics Observatory, or SDO, studies the Sun 24/7 and captured the entire seven-and-a-half-hour event. This composite image of Mercury’s journey across the sun was created with visible-light images from the Helioseismic and Magnetic Imager on SDO.

Image Credit: NASA/SDO

NASA's Kepler Mission Announces Largest Collection of Planets Ever Discovered: 1 284 New Planets

This artist's concept depicts select planetary discoveries made to date by NASA's Kepler space telescope.
This artist's concept depicts select planetary discoveries made to date by NASA's Kepler space telescope.
NASA's Kepler mission has verified 1 284 new planets – the single largest finding of planets to date.

“This announcement more than doubles the number of confirmed planets from Kepler,” said Ellen Stofan, chief scientist at NASA Headquarters in Washington. “This gives us hope that somewhere out there, around a star much like ours, we can eventually discover another Earth.”

Analysis was performed on the Kepler space telescope’s July 2015 planet candidate catalog, which identified 4 302 potential planets. For 1 284 of the candidates, the probability of being a planet is greater than 99 percent – the minimum required to earn the status of “planet.” An additional 1 327 candidates are more likely than not to be actual planets, but they do not meet the 99 percent threshold and will require additional study. The remaining 707 are more likely to be some other astrophysical phenomena. This analysis also validated 984 candidates previously verified by other techniques.

"Before the Kepler space telescope launched, we did not know whether exoplanets were rare or common in the galaxy. Thanks to Kepler and the research community, we now know there could be more planets than stars,” said Paul Hertz, Astrophysics Division director at NASA Headquarters. "This knowledge informs the future missions that are needed to take us ever-closer to finding out whether we are alone in the universe."

Kepler captures the discrete signals of distant planets – decreases in brightness that occur when planets pass in front of, or transit, their stars – much like the May 9 Mercury transit of our sun. Since the discovery of the first planets outside our solar system more than two decades ago, researchers have resorted to a laborious, one-by-one process of verifying suspected planets


This latest announcement, however, is based on a statistical analysis method that can be applied to many planet candidates simultaneously. Timothy Morton, associate research scholar at Princeton University in New Jersey and lead author of the scientific paper published in The Astrophysical Journal, employed a technique to assign each Kepler candidate a planet-hood probability percentage – the first such automated computation on this scale, as previous statistical techniques focused only on sub-groups within the greater list of planet candidates identified by Kepler.

"Planet candidates can be thought of like bread crumbs,” said Morton. “If you drop a few large crumbs on the floor, you can pick them up one by one. But, if you spill a whole bag of tiny crumbs, you're going to need a broom. This statistical analysis is our broom."

In the newly-validated batch of planets, nearly 550 could be rocky planets like Earth, based on their size. Nine of these orbit in their sun's habitable zone, which is the distance from a star where orbiting planets can have surface temperatures that allow liquid water to pool. With the addition of these nine, 21 exoplanets now are known to be members of this exclusive group.

"They say not to count our chickens before they're hatched, but that's exactly what these results allow us to do based on probabilities that each egg (candidate) will hatch into a chick (bona fide planet)," said Natalie Batalha, co-author of the paper and the Kepler mission scientist at NASA's Ames Research Center in Moffett Field, California. “This work will help Kepler reach its full potential by yielding a deeper understanding of the number of stars that harbor potentially habitable, Earth-size planets -- a number that's needed to design future missions to search for habitable environments and living worlds.”

Of the nearly 5 000 total planet candidates found to date, more than 3 200 now have been verified, and 2 325 of these were discovered by Kepler. Launched in March 2009, Kepler is the first NASA mission to find potentially habitable Earth-size planets. For four years, Kepler monitored 150 000 stars in a single patch of sky, measuring the tiny, telltale dip in the brightness of a star that can be produced by a transiting planet. In 2018, NASA’s Transiting Exoplanet Survey Satellite will use the same method to monitor 200 000 bright nearby stars and search for planets, focusing on Earth and Super-Earth-sized

Image Credit: NASA/W. Stenzel
Explanation from: https://www.nasa.gov/press-release/nasas-kepler-mission-announces-largest-collection-of-planets-ever-discovered

Earth seen by Himawari-8 Satellite from 22000 miles (35 400 km) away

Earth seen by Himawari-8 Satellite

Himawari-8 Satellite, Orbit of the Earth
February 10, 2016

Image Credit: NOAA/JMA

At least One in Six stars has an Earth-sized Planet

Earth-sized Planet

The quest to determine if planets like Earth are rare or common is taking another stride forward on the journey. Using NASA's Kepler spacecraft, managed by NASA Ames Research Center, astronomers are beginning to find Earth-sized planets orbiting distant stars. A analysis of Kepler data shows that about 17 percent of stars have an Earth-sized planet in an orbit closer than Mercury. Since the Milky Way has about 100 billion stars, there are at least 17 billion Earth-sized worlds out there.

The research team found that 50 percent of all stars have a planet of Earth-size or larger in a close orbit. By adding larger planets detected in wider orbits up to the orbital distance of the Earth, this number increases to 70 percent.

Extrapolating from Kepler's currently ongoing observations and results from other detection techniques, scientists have determined that nearly all sun-like stars have planets.

Planets closer to their stars are easier to find because they transit more frequently. As more data are gathered, planets in larger orbits will be detected. In particular, Kepler's extended mission will enable the detection of Earth-sized planets at greater distances, including Earth-like orbits in the "habitable zone," the region in a planetary system where liquid water might exist on the surface of an orbiting planet.

Image Credit: Credit: C. Pulliam & D. Aguilar (CfA)
Explanation from: https://www.nasa.gov/mission_pages/kepler/news/17-percent-of-stars-have-earth-size-planets.html

Center of the Milky Way Galaxy in X-rays

Center of the Milky Way Galaxy in X-rays

X-rays detected by the Chandra X-ray Observatory expose a wealth of exotic objects and high-energy features. In this image, pink represents lower energy X-rays and blue indicates higher energy. Hundreds of small dots show emission from material around black holes and other dense stellar objects. A supermassive black hole - some four million times more massive than the Sun - resides within the bright region in the lower right. The diffuse X-ray light comes from gas heated to millions of degrees by outflows from the supermassive black hole, winds from giant stars, and stellar explosions. This central region is the most energetic place in our galaxy.

Image Credit: NASA/CXC/UMass/D. Wang et al.
Explanation from: http://chandra.si.edu/photo/2009/galactic/more.html

May 9, 2016

The Milky Way Galaxy over Bosque Alegre Station in Argentina

The Milky Way Galaxy over Bosque Alegre Station in Argentina

Bosque Alegre Station, Argentina
September 2015

Image Credit & Copyright: Sebastián D' Alessandro

Spiral Galaxy NGC 4394

Spiral Galaxy NGC 4394

Discovered in 1784 by the German–British astronomer William Herschel, NGC 4394 is a barred spiral galaxy situated about 55 million light-years from Earth. The galaxy lies in the constellation of Coma Berenices (Berenice's Hair), and is considered to be a member of the Virgo Cluster.

NGC 4394 is the archetypal barred spiral galaxy, with bright spiral arms emerging from the ends of a bar that cuts through the galaxy’s central bulge. These arms are peppered with young blue stars, dark filaments of cosmic dust, and bright, fuzzy regions of active star formation. At the centre of NGC 4394 lies a region of ionised gas known as a LINER. LINERs are active regions that display a characteristic set of emission lines in their spectra— mostly weakly ionised atoms of oxygen, nitrogen and sulphur.

Although LINER galaxies are relatively common, it’s still unclear where the energy comes from to ionise the gas. In most cases it is thought to be the influence of a black hole at the centre of the galaxy, but it could also be the result of a high level of star formation. In the case of NGC 4394, it is likely that gravitational interaction with a nearby neighbour has caused gas to flow into the galaxy’s central region, providing a new reservoir of material to fuel the black hole or to make new stars.

Image Credit: ESA/Hubble, NASA, Judy Schmidt
Explanation from: https://www.spacetelescope.org/images/potw1618a/

Globular Cluster NGC 339

Globular Cluster NGC 339

This NASA/ESA Hubble Space Telescope image reveals the simple beauty of NGC 339, a massive intermediate age star cluster in the southern constellation of Tucana (The Toucan).

NGC 339 is part of the Small Magellanic Cloud (SMC), a dwarf galaxy that lies around 200 000 light-years away from us. Along with our own galaxy, the Milky Way, the SMC is one of a collection of neighbouring galaxies known as the Local Group.

By measuring the brightnesses and colours of the stars of NGC 339, astronomers were able to estimate the overall age of the cluster — a method that places NGC 339 at around 6.5 billion years old. This makes it only half the age of the more common globular clusters. The relationship between massive intermediate age star clusters, such as NGC 339, and the true globular clusters are not fully understood yet. So far none of these type of clusters has been found in the Milky Way.

In this very detailed image, it is also possible to see a number of galaxies. They appear as fuzzy, extended blobs, contrasting with the sharp stars that make up NGC 339. Most obvious here are two elliptical galaxies, one towards the top left of the image and another in the centre right. These galaxies are not associated with NGC 339 but lie far in the background, across the vast expanse of the cosmos.

Image Credit: ESA/Hubble, NASA, Judy Schmidt
Explanation from: https://www.spacetelescope.org/images/potw1617a/

May 8, 2016

Blue Marble: Eastern Hemisphere

Blue Marble: Eastern Hemisphere

This spectacular “blue marble” image is the most detailed true-color image of the entire Earth to date. Using a collection of satellite-based observations, scientists and visualizers stitched together months of observations of the land surface, oceans, sea ice, and clouds into a seamless, true-color mosaic of every square kilometer (.386 square mile) of our planet.

Much of the information contained in this image came from a single remote-sensing device-NASA’sModerate Resolution Imaging Spectroradiometer, or MODIS. Flying over 700 km above the Earth on board the Terra satellite, MODIS provides an integrated tool for observing a variety of terrestrial, oceanic, and atmospheric features of the Earth.

The land and coastal ocean portions of these images are based on surface observations collected from June through September 2001 and combined, or composited, every eight days to compensate for clouds that might block the sensor’s view of the surface on any single day. Two different types of ocean data were used in these images: shallow water true color data, and global ocean color (or chlorophyll) data. Topographic shading is based on the GTOPO 30 elevation dataset compiled by the U.S. Geological Survey’s EROS Data Center.

MODIS observations of polar sea ice were combined with observations of Antarctica made by the National Oceanic and Atmospheric Administration’s AVHRR sensor—the Advanced Very High Resolution Radiometer. The cloud image is a composite of two days of imagery collected in visible light wavelengths and a third day of thermal infra-red imagery over the poles. Global city lights, derived from 9 months of observations from the Defense Meteorological Satellite Program, are superimposed on a darkened land surface map.

Image Credit: NASA's Earth Observatory
Explanation from: http://visibleearth.nasa.gov/view.php?id=57723

A spiral galaxy that resembles our Milky Way

galaxy like milky way

ESO astronomers have used the Wide Field Imager on the MPG/ESO 2.2-metre telescope to capture an image of NGC 6744. This impressive spiral galaxy lies about 30 million light-years away in the southern constellation of Pavo (The Peacock). But this view could almost be a picture postcard of our own Milky Way, taken and sent by an extragalactic friend, as this galaxy closely resembles our own.

We see NGC 6744 almost face on, meaning we get a dramatic bird’s eye view of the galaxy’s structure. If we had the technology to escape the Milky Way and could look down on it from intergalactic space, this view is close to the one we would see — striking spiral arms wrapping around a dense, elongated nucleus and a dusty disc. There is even a distorted companion galaxy — NGC 6744A, seen here as a smudge to the lower right of NGC 6744, which is reminiscent of one of the Milky Way’s neighbouring Magellanic Clouds.

One difference between NGC 6744 and the Milky Way is their size. While our galaxy is roughly 100 000 light-years across, the galaxy pictured here extends to almost twice this diameter. Nevertheless, NGC 6744 gives us a tantalising sense of how a distant observer might see our own galactic home.

This dramatic object is one of the largest and nearest spiral galaxies. Although it has a brightness of about 60 billion Suns, its light spreads across a large area in the sky — about two thirds the width of the full Moon, making the galaxy appear as a hazy glow with a bright centre through a small telescope. Still, it is one of the most beautiful objects in the southern sky, and it can be identified by amateur astronomers as an oval shape contrasting with a rich background of stars.

With professional telescopes such as the MPG/ESO 2.2-metre telescope at La Silla, which captured this image, NGC 6744 can be seen in all its glory. The dusty spiral arms are home to many glowing star-forming regions (seen in red) and give this Milky Way look-alike its striking spiral form.

This picture was taken by the Wide Field Imager attached to the MPG/ESO 2.2-metre telescope at ESO’s La Silla Observatory in Chile. The picture was created from exposures taken through four different filters that passed blue, yellow-green and red light and the glow coming from hydrogen gas. These are shown in this picture as blue, green, orange and red, respectively.

Image Credit: ESO
Explanation from: https://www.eso.org/public/news/eso1118/

NASA’s Spitzer Maps Climate Patterns on a Super-Earth

NASA’s Spitzer Maps Climate Patterns on a Super-Earth

Observations from NASA's Spitzer Space Telescope have led to the first temperature map of a super-Earth planet -- a rocky planet nearly two times as big as ours. The map reveals extreme temperature swings from one side of the planet to the other, and hints that a possible reason for this is the presence of lava flows.

"Our view of this planet keeps evolving," said Brice Olivier Demory of the University of Cambridge, England, lead author of a new report appearing in the March 30 issue of the journal Nature. "The latest findings tell us the planet has hot nights and significantly hotter days. This indicates the planet inefficiently transports heat around the planet. We propose this could be explained by an atmosphere that would exist only on the day side of the planet, or by lava flows at the planet surface."

The toasty super-Earth 55 Cancri e is relatively close to Earth at 40 light-years away. It orbits very close to its star, whipping around it every 18 hours. Because of the planet's proximity to the star, it is tidally locked by gravity just as our moon is to Earth. That means one side of 55 Cancri, referred to as the day side, is always cooking under the intense heat of its star, while the night side remains in the dark and is much cooler.

"Spitzer observed the phases of 55 Cancri e, similar to the phases of the moon as seen from the Earth. We were able to observe the first, last quarters, new and full phases of this small exoplanet," said Demory. "In return, these observations helped us build a map of the planet. This map informs us which regions are hot on the planet."

Spitzer stared at the planet with its infrared vision for a total of 80 hours, watching it orbit all the way around its star multiple times. These data allowed scientists to map temperature changes across the entire planet. To their surprise, they found a dramatic temperature difference of 2,340 degrees Fahrenheit (1,300 Kelvin) from one side of the planet to the other. The hottest side is nearly 4,400 degrees Fahrenheit (2,700 Kelvin), and the coolest is 2,060 degrees Fahrenheit (1,400 Kelvin).

The fact Spitzer found the night side to be significantly colder than the day side means heat is not being distributed around the planet very well. The data argues against the notion that a thick atmosphere and winds are moving heat around the planet as previously thought. Instead, the findings suggest a planet devoid of a massive atmosphere, and possibly hint at a lava world where the lava would become hardened on the night side and unable to transport heat.

"The day side could possibly have rivers of lava and big pools of extremely hot magma, but we think the night side would have solidified lava flows like those found in Hawaii," said Michael Gillon, University of Liège, Belgium.

The Spitzer data also revealed the hottest spot on the planet has shifted over a bit from where it was expected to be: directly under the blazing star. This shift either indicates some degree of heat recirculation confined to the day side, or points to surface features with extremely high temperatures, such as lava flows.

Additional observations, including from NASA's upcoming James Webb Space Telescope, will help to confirm the true nature of 55 Cancri e.

The new Spitzer observations of 55 Cancri are more detailed thanks to the telescope’s increased sensitivity to exoplanets. Over the past several years, scientists and engineers have figured out new ways to enhance Spitzer’s ability to measure changes in the brightness of exoplanet systems. One method involves precisely characterizing Spitzer’s detectors, specifically measuring “the sweet spot” -- a single pixel on the detector -- which was determined to be optimal for exoplanet studies.

“By understanding the characteristics of the instrument -- and using novel calibration techniques of a small region of a single pixel -- we are attempting to eke out every bit of science possible from a detector that was not designed for this type of high-precision observation,” said Jessica Krick of NASA’s Spitzer Space Science Center, at the California Institute of Technology in Pasadena.

Image Credit: NASA/JPL-Caltech/University of Cambridge
Explanation from: https://www.nasa.gov/press-release/nasa-s-spitzer-maps-climate-patterns-on-a-super-earth