I like astronomy, archaeology, photography, music and drinking a lot of tea. I hate politics. Something that annoys me: that I shall not respect the permanence, and to take me by what I'm not. The best sign: VIRGO. The worst: the health. The best: adapt and know how to get ahead. FIRST BLOG: esplaobs.blogspot.com, SECOND BLOG: esplaobs02.blogspot.com, RETRO BLOG: esplaobs01.blogspot.com, YOUTUBE CHANNELS: esplaobs, esplaobs. ext02. Instagram: esplaobsrosario. Welcome to my BLOGs !
Saturday, March 31, 2018
FULL MOON, FULL BLOSSOM, EASTER MOON Taken by Shiraishi on March 31, 2018 @ Kumagaya-shi, Saitama, Japan
Full cherry-blossom trees with full moon.
Tonight is the 2nd full moon in March, and the 2nd full moon opportunity itself is the 2nd time in this year (1st time in January).
In my city cherry blossoms have been in full bloom.
Full blossom with full moon can be seen for the first time in several years.
And this full moon is also Easter moon.
Sony ILCE-7S digital camera; ISO 1250, F6.3, 1/160s exposure to ISO 8000, F6.3, 1/100s exposure, f=160mm, 140s interval
RISING MOON Taken by Yasushi Aoshima on March 30, 2018 @ Ishikawa, JAPAN
Rising Moon from Mt. Hakusan.
Data: EF300mmF2.8L USM (at F5.6), CanonEOS6D, 100 ISO, 1/750 sec each,
1) 118 frames GIF (8:34:50-38:44 UT),
2) 8:37:44 UT
TWILIGHT IN A WESTERN SKY Image Credit & Copyright: Stan Honda
A slender crescent Moon and inner planets Venus and Mercury never wander far from the Sun in planet Earth's skies. In the fading evening twilight of March 18, they line up near the western horizon in this atmospheric skyscape. While the celestial scene was enjoyed around the world, this photo captures the trio, with fainter Mercury at the far right, above the crags of Big Bend National Park in southwest Texas. Tonight the Moon will be full though, and rise opposite the Sun. Look for it high in the sky at midnight, near bright star Spica.
Friday, March 30, 2018
AURORAS Taken by Carlos Gauna on March 24, 2018 @ Iceland
Ive been in Iceland for the last couple weeks. Always travel there for equinox. This year did not disappoint. Here are some images taken between March 17th and March 24th, 2018
THE MOON TOWARDS FULL Taken by Maximilian Teodorescu on March 30, 2018 @ near Bucharest, Romania
Tonight, it was way to impressive in the field at my observing location, so I just had to shoot the Moon…
4.5 Refractor, ASI 1600MM at the focal plane, red filter. 600 frames out of 1000.
WAVELENGTH COMPARISONS
We ran together three sequences of the sun taken in three different extreme ultraviolet wavelengths to better illustrate how different features that appear in one sequence are difficult if not impossible to see in the others (Mar. 20-21, 2018). In the red sequence (304 Angstroms), we can see very small spicules and some small prominences at the sun's edge, which are not easy to see in the other two sequences. In the second clip (193 Angstroms), we can readily observe the large and dark coronal hole, though it is difficult to male out in the others. In the third clip (171 wavelengths), we can see strands of plasma waving above the surface, especially above the one small, but bright, active region near the right edge. And these are just three of the 10 extreme ultraviolet wavelengths in which SDO images the sun every 12 seconds every day. That's a lot of data and a lot of science.
Credit: Solar Dynamics Observatory, NASA.
NGC 247 AND FRIENDS Image Credit & Copyright: CHART32 Team, Processing - Johannes Schedler
About 70,000 light-years across, NGC 247 is a spiral galaxy smaller than our Milky Way. Measured to be only 11 million light-years distant it is nearby though. Tilted nearly edge-on as seen from our perspective, it dominates this telescopic field of view toward the southern constellation Cetus. The pronounced void on one side of the galaxy's disk recalls for some its popular name, the Needle's Eye galaxy. Many background galaxies are visible in this sharp galaxy portrait, including the remarkable string of four galaxies just below and left of NGC 247 known as Burbidge's Chain. Burbidge's Chain galaxies are about 300 million light-years distant. The deep image even reveals that the two leftmost galaxies in the chain are apparently interacting, joined by a faint bridge of material. NGC 247 itself is part of the Sculptor Group of galaxies along with the shiny spiral NGC 253.
Thursday, March 29, 2018
WHAT SOUTHERN STARGAZERS LONG TO SEE IN NORTHERN SKIES BY: BOB KING
http://www.skyandtelescope.com/observing/what-southern-stargazers-long-to-see-in-northern-skies/
Southern objects like Omega Centauri and the Magellanic Clouds make observers in the Northern Hemisphere envious. Today, we turn the tables and find out what those living in negative latitudes would love to see up north.
The grass is always greener, right? A lot of us in the Northern Hemisphere have southern sky envy. We pine after Omega Centauri, the Magellanic Clouds, 47 Tucanae, the Southern Cross, and to one day see the Sagittarius Milky Way cross the zenith. Observers below the equator have most of the good stuff, right?
Having lived in one hemisphere for so long, it's easy to lose perspective. That's why I poked around and tried to get a feel for what the other half thought. What do observers in the Southern Hemisphere wish they could see in northern skies? What would I show someone from Sydney if they came for a visit?
Since "southerners" have to put up with the obscure magnitude-5.5 Sigma Octantis as their Pole Star, I figured Polaris would top the list. It was a must-see for some, but the big vote getters were notable deep-sky objects: the M81/82 galaxy pair; the Double Cluster in Perseus (there's nothing quite like it down south, I'm told); the Andromeda and Whirlpool galaxies (M31 and M51); NGC 457 (ET or Owl Cluster); NGC 7000; the North America Nebula; M97 (Owl Nebula); and the Great Hercules Globular, M13. On the last, we all know it doesn't hold a standard candle to Omega Centauri, but with all the good press it's had for the past couple centuries, it remains high on the list.
"For my money the best sights not visible from significantly south of the celestial equator are the Double Cluster and the M81/M82 pair," wrote Tony Flanders, former Associate Editor at Sky & Telescope. These two were probably the most often mentioned by the other observers I polled.
For northerners, Alpha Centauri, Proxima Centauri, and the triple star, Alpha Crucis, are among the individual stars we'd love to get our eyes on. Southern skywatchers look forward to seeing Mizar, Delta Cephei (the most famous of the Cepheid variables), and the famous quadruple Epsilon Lyrae (aka, the Double Double). Poor seeing often mars the view of Epsilon, which stands only 15°–20° high at culmination.
While many northern sights are visible from, say, Australia and southern South America, they're often low in the sky and compromised the same way southern deep-sky objects are for northerners. How many times have you wished the Lagoon Nebula or Silver Coin Galaxy (NGC 253) were just 10° higher, if only to save your knees? Southerners suffer similarly. You guys must hunch over for the Ring Nebula (how lucky we are to see it near the zenith!), Andromeda Galaxy, M13, the Triangulum Galaxy (M33), and Auriga's sparking open clusters.
We in the polar-bear hemisphere may be put off by Pegasus flying upside down or Hercules walking on his hands, but observers below the equator have it much worse. Orion, Leo, Lyra, and a host of other constellations are decidedly upside down from Down Under. This fact was appreciated by Glen Chapman, who lived in Sydney, Australia (latitude –33.8° S) before moving to western Kansas in 2008:
"As a transplanted southerner I was fascinated with seeing Orion standing right way up." On the plus side, southern skywatchers get to see Pegasus prance from east to west with its head held high and legs pointed down, while Hercules strides across the north with his dignity.
Chapman continued: "M57 was high on the list because we really don't have anything in the south to compare. The LMC (Large Magellanic Cloud) and SMC (Small Magellanic Cloud) often get touted as being far superior. Unfortunately, unless you're under dark skies you really don't get the totality of these two objects. With M31 I get virtually the whole galaxy in one field of view that looks like the traditional idea of a galaxy.
"M51 ended up being one of the first objects I observed. I was astonished to see two galactic cores in the eyepiece and remains to this day a firm favorite. (The) North America Nebula was on my bucket list but I never thought I would get the opportunity to view it (even in the US). A really lovely object. Overall I was keen to observe and identify the northern circumpolar constellations. Ursa Major did not really impress me. But I truly enjoyed identifying Cygnus and Cassiopeia. Even after these years I like to lay back and just imagine Cygnus as a giant swan, wings outstretched flying along the Milky Way."
While I've concentrated mostly on telescopic sights, the Northern Hemisphere has one big drawing card the Southern doesn't — relatively easy access to the aurora. While both the aurora borealis and aurora australis have virtually equal intensities, there's far less populated land within or near the southern auroral oval compared to the northern. Skywatchers in Canada, the northern United States, and Nordic nations routinely witness the spectacle, as do the scant few living in or traveling to Antarctica.
Of course, the aurora is visible from New Zealand, Tasmania, southern South America, and even parts of Australia, but with less frequency and, in general, less intensity. It all has to do with distance from the oval. Similarly, southern skywatchers who don't head north will never complete the Messier catalog with M52, M103, M97 (Owl Nebula), M76, M101, M81/82, and others forever hidden by an immovable horizon.
Here's my list of Top 17 best northern sky sights either invisible or compromised by altitude for southern observers. Most came through polling, a few are my own:
For a more extensive list, try amateur astronomer Donald Pensack's Northern Objects for Southern Observers, a compilation of 188 northern nuggets. Whichever hemisphere you call home, I hope you'll have the opportunity to visit the other. I guarantee it will be the astronomical adventure of a lifetime.
Southern objects like Omega Centauri and the Magellanic Clouds make observers in the Northern Hemisphere envious. Today, we turn the tables and find out what those living in negative latitudes would love to see up north.
The Double Cluster in Perseus (NGC 869–NGC 884) rates high on Southern Hemisphere observers' wishlists.
Chris Schur
Having lived in one hemisphere for so long, it's easy to lose perspective. That's why I poked around and tried to get a feel for what the other half thought. What do observers in the Southern Hemisphere wish they could see in northern skies? What would I show someone from Sydney if they came for a visit?
Since "southerners" have to put up with the obscure magnitude-5.5 Sigma Octantis as their Pole Star, I figured Polaris would top the list. It was a must-see for some, but the big vote getters were notable deep-sky objects: the M81/82 galaxy pair; the Double Cluster in Perseus (there's nothing quite like it down south, I'm told); the Andromeda and Whirlpool galaxies (M31 and M51); NGC 457 (ET or Owl Cluster); NGC 7000; the North America Nebula; M97 (Owl Nebula); and the Great Hercules Globular, M13. On the last, we all know it doesn't hold a standard candle to Omega Centauri, but with all the good press it's had for the past couple centuries, it remains high on the list.
The bright pair of galaxies, M81 (left) and M82 in Ursa Major is another sought-after sight for southern observers.
Erik Guneriussen
"For my money the best sights not visible from significantly south of the celestial equator are the Double Cluster and the M81/M82 pair," wrote Tony Flanders, former Associate Editor at Sky & Telescope. These two were probably the most often mentioned by the other observers I polled.
For northerners, Alpha Centauri, Proxima Centauri, and the triple star, Alpha Crucis, are among the individual stars we'd love to get our eyes on. Southern skywatchers look forward to seeing Mizar, Delta Cephei (the most famous of the Cepheid variables), and the famous quadruple Epsilon Lyrae (aka, the Double Double). Poor seeing often mars the view of Epsilon, which stands only 15°–20° high at culmination.
This view of the northern sky from latitude 32° S shows favorite northern constellations battling low altitude the same way Sagittarius and Scorpius do for northerners. For southern observers, these are all winter figures.
Stellarium
While many northern sights are visible from, say, Australia and southern South America, they're often low in the sky and compromised the same way southern deep-sky objects are for northerners. How many times have you wished the Lagoon Nebula or Silver Coin Galaxy (NGC 253) were just 10° higher, if only to save your knees? Southerners suffer similarly. You guys must hunch over for the Ring Nebula (how lucky we are to see it near the zenith!), Andromeda Galaxy, M13, the Triangulum Galaxy (M33), and Auriga's sparking open clusters.
We in the polar-bear hemisphere may be put off by Pegasus flying upside down or Hercules walking on his hands, but observers below the equator have it much worse. Orion, Leo, Lyra, and a host of other constellations are decidedly upside down from Down Under. This fact was appreciated by Glen Chapman, who lived in Sydney, Australia (latitude –33.8° S) before moving to western Kansas in 2008:
Orion (top right) stands upside down outside Carnegie Las Campanas observatory in the Atacama desert in Chile at latitude 29° S.
Yuri Beletsky
"As a transplanted southerner I was fascinated with seeing Orion standing right way up." On the plus side, southern skywatchers get to see Pegasus prance from east to west with its head held high and legs pointed down, while Hercules strides across the north with his dignity.
Chapman continued: "M57 was high on the list because we really don't have anything in the south to compare. The LMC (Large Magellanic Cloud) and SMC (Small Magellanic Cloud) often get touted as being far superior. Unfortunately, unless you're under dark skies you really don't get the totality of these two objects. With M31 I get virtually the whole galaxy in one field of view that looks like the traditional idea of a galaxy.
"M51 ended up being one of the first objects I observed. I was astonished to see two galactic cores in the eyepiece and remains to this day a firm favorite. (The) North America Nebula was on my bucket list but I never thought I would get the opportunity to view it (even in the US). A really lovely object. Overall I was keen to observe and identify the northern circumpolar constellations. Ursa Major did not really impress me. But I truly enjoyed identifying Cygnus and Cassiopeia. Even after these years I like to lay back and just imagine Cygnus as a giant swan, wings outstretched flying along the Milky Way."
Two auroral ovals crown the Earth as seen in this depiction on March 27, 2018. Notice how the northern oval, even when the aurora isn't particularly active, hovers over a fair amount of populated land, while the southern oval does not — except for Antarctica.
NOAA / SWPC
While I've concentrated mostly on telescopic sights, the Northern Hemisphere has one big drawing card the Southern doesn't — relatively easy access to the aurora. While both the aurora borealis and aurora australis have virtually equal intensities, there's far less populated land within or near the southern auroral oval compared to the northern. Skywatchers in Canada, the northern United States, and Nordic nations routinely witness the spectacle, as do the scant few living in or traveling to Antarctica.
Of course, the aurora is visible from New Zealand, Tasmania, southern South America, and even parts of Australia, but with less frequency and, in general, less intensity. It all has to do with distance from the oval. Similarly, southern skywatchers who don't head north will never complete the Messier catalog with M52, M103, M97 (Owl Nebula), M76, M101, M81/82, and others forever hidden by an immovable horizon.
Here's my list of Top 17 best northern sky sights either invisible or compromised by altitude for southern observers. Most came through polling, a few are my own:
- M81/M82
- Perseus Double Cluster
- Whirlpool Galaxy (M51)
- Andromeda Galaxy (M31)
- Pinwheel Galaxy (M33)
- Great Hercules Globular (M13)
- Cat's Eye Nebula (NGC 6543)
- ET/Owl Cluster (NGC 457)
- M103
- The "W" of Cassiopeia (surely as impressive as the Southern Cross)
- Ring Nebula (M57) — especially if you were keen on the oft-sought central star
- Polaris (come on, you can't beat a real Pole Star!)
- Veil Nebula (NGC 6960/NGC 6992)
- North America Nebula (NGC 7000)
- Mizar (& Alcor)
- Perseid and Geminid meteor showers. The two strongest and most reliable yearly showers have considerably northern radiants
- Aurora borealis
The northern winter constellations cruise low across the northern sky for viewers at southern latitudes. On the plus side, they can be observed in summertime weather.
Stellarium
PROBA’S LOOKS AT PYRAMIDS
This beautiful look at the Egyptian pyramids is courtesy of the Proba-1 satellite and ESA.
ESA — A view looking north to south of Egypt’s famous Giza Pyramid Complex, as seen by ESA’s Proba-1 minisatellite.
The smaller Pyramid of Menkaure is seen to towards the centre of the image, with the larger Pyramid of Khafre down and left of it, with the Great Pyramid of Giza – the largest and oldest of the three – below and left of that.
Three smaller pyramids are adjacent to the Pyramid Menkaure. The Giza Plateau sits on the edge of Cairo, fringed by suburbs.
The cubic-metre Proba-1 is the first in ESA’s series of satellites aimed at flight-testing new space technologies. It was launched on 22 October 2001 but is still going strong, having recently became the Agency’s longest-serving Earth-observing mission.
Proba-1’s main hyperspectral CHRIS imager is supplemented by this experimental High-Resolution Camera, acquiring black and white 5 m-resolution images.
Other innovations include what were then novel gallium-arsenide solar cells, the use of startrackers for gyroless attitude control, one of the first lithium-ion batteries – now the longest such item operating in orbit – and one of ESA’s first ERC32 microprocessors to run Proba-1’s agile computer.
For more background on Proba-1, read this celebration in the ESA Bulletin.
Proba-1 led the way for the Sun-monitoring Proba-2 in 2009, the vegetation-tracking Proba-V in 2013 and the Proba-3 precise formation-flying mission planned for late 2020.
This image was acquired on 6 January 2018.
PRÓXIMAMENTE EN PLANETARIO CIUDAD DE ROSARIO....... NUEVA FUNCIÓN PARA CHICOS " EL CIELO DE TU PATIO " //// SELECCIÓN MUSICAL: ESMERALDA SOSA
FUNCIÓN PLANETARIO CIUDAD DE ROSARIO
" EL CIELO DE TU PATIO "
PERSONAL TÉCNICO PLANETARIO CIUDAD DE ROSARIO
GUSTAVO ARIAS
( Jefe Técnico de Instrumental y Periféricos )
ESMERALDA SOSA
ANDREA COSTA
RAÚL BARONTINI
GUILLERMO GARCIA
JUAN IGNACIO GERINI
ANDREA JIMENEZ
LISTADO DE TEMAS
" Forest Groove " - KEVIN WOOD
" Treasure " - AMETHYSTIUM
" Will & Penny´s Theme " - APOLLO 440 - LOST IN SPACE SOUNDTRACK
" La Noche se abre a La Luna " - LEÓN GIECO
" Vol de Nuit " - PAUL SCHWARTZ
" Recognizer " - DAFT PUNK - TRON LEGACY SOUNDTRACK
" The Ice Dance " - EDWARD SCISSORDSHANDS SOUNDTRACK - DANNY ELFMAN
" Optical illusions " - William Orbit
" The Son of Flynn " - DAFT PUNK - TRON LEGACY SOUNDTRACK
" Rhythm of the Night " - EARTH TRYBE - DAVID ARKENSTONE
" Lost Tribe " - INTERMIX
" Amber Light " & " The Millenium Bell " - MIKE OLDFIELD
MARZO - 2018
PARA DESCARGAR MÚSICA ABRIR DEL SIGUIENTE LINK:
https://drive.google.com/drive/folders/1fjfrKdwMtgeEee8-GLAIKs3dpNfMWQcP?usp=sharing
https://drive.google.com/drive/folders/1fjfrKdwMtgeEee8-GLAIKs3dpNfMWQcP?usp=sharing
PRÓXIMAMENTE EN PLANETARIO CIUDAD DE ROSARIO....... NUEVA FUNCIÓN PARA PUBLICO EN GENERAL " ASTROCUENTOS " //// SELECCIÓN MUSICAL: ESMERALDA SOSA
FUNCIÓN PLANETARIO CIUDAD DE ROSARIO
" ASTROCUENTOS "
PERSONAL TÉCNICO PLANETARIO CIUDAD DE ROSARIO
GUSTAVO ARIAS
( Jefe Técnico de Instrumental y Periféricos )
ESMERALDA SOSA
ANDREA COSTA
RAÚL BARONTINI
GUILLERMO GARCIA
JUAN IGNACIO GERINI
ANDREA JIMENEZ
LISTADO DE TEMAS
- " Dedication & Windsong " JAMES HORNER - MIGHTY JOE YOUNG SOUNDTRACK
- " Monte Tierra Cautiva " TONOLEC
- " Plegaria del Arbol Negro " TONOLEC
- " Journey into the Stillness " GARY STROUTS
- " Moonflower " DAVID ARKENSTONE
- " The Painted Sails " DAVID ARKENSTONE
- " Creation of Earth " THOMAS BERGENSEN
- " Equis Fair " DAVID ARKENSTONE
- " Ly - o - Lay Ale Loya " ( Circle Dance Sing ) SACRED SPIRITS
- " To the Stars " RANDY EDELMAN DRAGONHEART SOUNDTRACK
MARZO - 2018
TAMBIÉN SE PUEDE ABRIR DEL SIGUIENTE LINK:
Wednesday, March 28, 2018
NEW NOVA IN CANIS MAJOR Taken by Maximilian Teodorescu on March 28, 2018 @ near Bucharest, Romania
There is a new star in the constellation of the Great Dog, with the poetic name ....
N CMa 2018 = TCP J07134590-2112330
I had a chance at imaging it before it got too low in the sky, and estimated a magnitude of +9.7 (V). The nova is brightening.
A CONJUNCTION OF PLANETS Taken by Nima Asadzadeh on March 26, 2018 @ Lake Urmia, Iran
A conjunction of Jupiter, Mars and Saturn with the center of the milky way over Lake Urmia.
Details: Panorama of 33 vertical shots. Nikon D7200, Nikkor 18-140. Shutter Speed 20, ISO Speed 3200, Aperture f/4.5, Focal 18mm.
Tuesday, March 27, 2018
IRIDESCENCE CLOUDS Taken by Doug Backlund on March 26, 2018 @ Ajo, AZ
I saw these clouds shortly after sunset from Ajo, AZ. Venus is just below the clouds. Childs Mountain in the background.
MARS BETWEEN NEBULAS Image Credit & Copyright: Sebastian Voltmer
What that bright red spot between the Lagoon and Trifid Nebulas? Mars. This gorgeous color deep-sky photograph captured the red planet passing between the two notable nebulas -- cataloged by the 18th century cosmic registrar Charles Messier as M8 and M20. M20 (upper right of center), the Trifid Nebula, presents a striking contrast in red/blue colors and dark dust lanes. Across the bottom right is the expansive, alluring red glow of M8, the Lagoon Nebula. Both nebulae are a few thousand light-years distant. By comparison, temporarily situated between them both, is the dominant "local" celestial beacon Mars. Taken last week, the red planet was only about 10 light-minutes
Monday, March 26, 2018
KEPLER BEYOND PLANETS: FINDING EXPLODING STARS
Astronomer Ed Shaya was in his office looking at data from NASA’s Kepler space telescope in 2012 when he noticed something unusual: The light from a galaxy had quickly brightened by 10 percent. The sudden bump in light got Shaya instantly excited, but also nervous. The effect could be explained by the massive explosion of a star -- a supernova! -- or, more troublingly, a computer error.
“I just remember on that day, not knowing whether I should believe it or not,” he remembers. Rather than celebrate, he thought, “Did I make a mistake? Am I doing this all wrong?”
This animation shows a kind of stellar explosion called a Fast-Evolving Luminous Transient. In this case, a giant star “burps” out a shell of gas and dust about a year before exploding. Most of the energy from the supernova turns into light when it hits this previously ejected material, resulting in a short, but brilliant burst of radiation.
Credits: NASA/JPL-Caltech
Stellar explosions forge and distribute materials that make up the world in which we live, and also hold clues to how fast the universe is expanding. By understanding supernovae, scientists can unlock mysteries that are key to what we are made of and the fate of our universe. But to get the full picture, scientists must observe supernovae from a variety of perspectives, especially in the first moments of the explosion. That’s really difficult -- there’s no telling when or where a supernova might happen next.
A small group of astronomers, including Shaya, realized Kepler could offer a new technique for supernova-hunting. Launched in 2009, Kepler is best known for having discovered thousands of exoplanets. But as a telescope that stares at single patches of space for long periods of time, it can capture a vast trove of other cosmic treasures --especially the kind that change rapidly or pop in and out of view, like supernovae.
“Kepler opened up a new way of looking at the sky,” said Jessie Dotson, Kepler’s project scientist, based at NASA’s Ames Research Center in California’s Silicon Valley. “It was designed to do one thing really well, which was to find planets around other stars. In order to do that, it had to deliver high-precision, continuous data, which has been valuable for other areas of astronomy.”
Originally, Shaya and colleagues were looking for active galactic nuclei in their Kepler data. An active galactic nucleus is an extremely bright area at the center of a galaxy where a voracious black hole is surrounded by a disk of hot gas. They had thought about searching for supernovae, but since supernovae are such rare events, they didn’t mention it in their proposal. “It was too iffy,” Shaya said.
Unsure if the supernova signal he found was real, Shaya and his University of Maryland colleague Robert Olling spent months developing software to better calibrate Kepler data, taking into account variations in temperature and pointing of the instrument. Still, the supernova signal persisted. In fact, they found five more supernovae in their Kepler sample of more than 400 galaxies. When Olling showed one of the signals to Armin Rest, who is now an astronomer at the Space Telescope Science Institute in Baltlimore, Rest’s jaw dropped. “I started to drool,” he said. The door had opened to a new way of tracking and understanding stellar explosions.
Today, these astronomers are part of the Kepler Extra-Galactic Survey, a collaboration between seven scientists in the United States, Australia and Chile looking for supernovae and active galactic nuclei to explore the physics of our universe. To date, they have found more than 20 supernovae using data from the Kepler spacecraft, including an exotic type reported by Rest in a new study in Nature Astronomy.
“We have some of the best-understood supernovae,” said Brad Tucker, astronomer at the Mt. Stromlo Observatory at the Australian National University, who is part of the Kepler Extra-Galactic Survey.
This animation shows the explosion of a white dwarf, an extremely dense remnant of a star that can no longer burn nuclear fuel at its core. In this “type Ia” supernova, white dwarf’s gravity steals material away from a nearby stellar companion. When the white dwarf reaches an estimated 1.4 times the current mass of the Sun, it can no longer sustain its own weight, and blows up.
Credits: NASA/JPL-Caltech
Why do we care about supernovae?
A longstanding mystery in astrophysics is how and why stars explode in different ways. One kind of supernova happens when a dense, dead star called a white dwarf explodes. A second kind happens when a single gigantic star nears the end of its life, and its core can no longer withstand the gravitational forces acting on it. The details of these general categories are still being worked out.
The first kind, called “type Ia” (pronounced as “one a”) is special because the intrinsic brightness of each of these supernovae is almost the same. Astronomers have used this standard property to measure the expansion of the universe and found the more distant supernovae were less bright than expected. This indicated they were farther away than scientists had thought, as the light had become stretched out over expanding space. This proved that the universe is expanding at an accelerating rate and earned those researchers the Nobel Prize in 2011. The leading theory is that a mysterious force called “dark energy” is pushing everything in the universe apart from everything else, faster and faster.
But as astronomers find more and more examples of type Ia explosions, including with Kepler, they realize not all are created equal. While some of these supernovae happen when a white dwarf robs its companion of too much matter, others are the result of two white dwarfs merging. In fact, the white dwarf mergers may be more common. More supernova research with Kepler will help astronomers on a quest to find out if different type Ia mechanisms result in some supernovae being brighter than others -- which would throw a wrench into how they are used to measure the universe’s expansion.
“To get a better idea of constraining dark energy, we have to understand better how these type Ia supernovae are formed,” Rest said.
This animation shows the merger of two white dwarfs. A white dwarf is an extremely dense remnant of a star that can no longer burn nuclear fuel at its core. This is another way that a “type Ia” supernova occurs.
Credits: NASA/JPL-Caltech
Another kind of supernova, the “core collapse” variety, happens when a massive star ends its life in an explosion. This includes “Type II” supernovae. These supernovae have a characteristic shockwave called the “shock breakout,” which was captured for the first time in optical light by Kepler. The Kepler Extra-Galactic Survey team, led by team member Peter Garnavich, an astrophysics professor at the University of Notre Dame in Indiana, spotted this shock breakout in 2011 Kepler data from a supernova called KSN 2011d, an explosion from a star roughly 500 times the size of our Sun. Surprisingly, the team did not find a shock breakout in a smaller type II supernova called KSN 2011a, whose star was 300 times the size of the Sun -- but instead found the supernova nestled in a layer of dust, suggesting that there is diversity in type II stellar explosions, too.
Kepler data have revealed other mysteries about supernovae. The new study led by Rest in Nature Astronomy describes a supernova from data captured by Kepler’s extended mission, called K2, that reaches its peak brightness in just a little over two days, about 10 times less than others take. It is the most extreme known example of a “fast-evolving luminous transient” (FELT) supernova. FELTs are about as bright as the type Ia variety, but rise in less than 10 days and fade in about 30. It is possible that the star spewed out a dense shell of gas about a year before the explosion, and when the supernova happened, ejected material hit the shell. The energy released in that collision would explain the quick brightening.
Why Kepler?
Telescopes on Earth offer a lot of information about exploding stars, but only over short periods of time -- and only when the Sun goes down and the sky is clear — so it’s hard to document the “before” and “after” effects of these explosions. Kepler, on the other hand, offers astronomers the rare opportunity to monitor single patches of sky continuously for months, like a car’s dashboard camera that is always recording. In fact, the primary Kepler mission, which ran from 2009 to 2013, delivered four years of observations of the same field of view, snapping a picture about every 30 minutes. In the extended K2 mission, the telescope is holding its gaze steady for up to about three months.
This animation shows a gigantic star exploding in a “core collapse” supernova. As molecules fuse inside the star, eventually the star can’t support its own weight anymore. Gravity makes the star collapse on itself. Core collapse supernovae are called type Ib, Ic, or II depending on the chemical elements present.
Credits: NASA/JPL-Caltech
With ground-based telescopes, astronomers can tell the supernova’s color and how it changes with time, which lets them figure out what chemicals are present in the explosion. The supernova’s composition helps determine the type of star that exploded. Kepler, on the other hand, reveals how and why the star explodes, and the details of how the explosion progresses. Using the two datasets together, astronomers can get fuller pictures of supernovae behavior than ever before.
Kepler mission planners revived the telescope in 2013, after the malfunction of the second of its four reaction wheels -- devices that help control the orientation of the spacecraft. In the configuration called K2, it needs to rotate every three months or so -- marking observing “campaigns.” Members of the Kepler Extra-Galactic Survey made the case that in the K2 mission, Kepler could still monitor supernovae and other exotic, distant astrophysical objects, in addition to exoplanets.
The possibilities were so exciting that the Kepler team devised two K2 observing campaigns especially useful for coordinating supernovae studies with ground-based telescopes. Campaign 16, which began on Dec. 7, 2017, and ended Feb. 25, 2018, included 9,000 galaxies. There are about 14,000 in Campaign 17, which is just beginning now. In both campaigns, Kepler faces in the direction of Earth so that observers on the ground can see the same patch of sky as the spacecraft. The campaigns have excited a community of researchers who can advantage of this rare coordination between Kepler and telescopes on the ground.
A guide to Supernovae infographic
A recent possible sighting got astronomers riled up on Super Bowl Sunday this year, even if they weren’t into the game. On that “super” day, the All Sky Automated Survey for SuperNovae (ASASSN) reported a supernova in the same nearby galaxy Kepler was monitoring. This is just one of many candidate events that scientists are excited to follow up on and perhaps use to better understand the secrets of the universe.
A few more supernovae may come from NASA’s Transiting Exoplanet Survey Satellite, (TESS) which is expected to launch on April 16. In the meantime, scientists will have a lot of work ahead of them once they receive the full dataset from K2’s supernova-focused campaigns.
“It will be a treasure trove of supernova information for years to come,” Tucker said.
Ames manages the Kepler and K2 missions for NASA's Science Mission Directorate. NASA's Jet Propulsion Laboratory in Pasadena, California, managed Kepler mission development. Ball Aerospace & Technologies Corporation operates the flight system with support from the Laboratory for Atmospheric and Space Physics at the University of Colorado in Boulder.
For more information about the Kepler mission, visit:
https://www.nasa.gov/kepler
Calla Cofield
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-1821
calla.e.cofield@jpl.nasa.gov
Alison Hawkes
Ames Research Center, California's Silicon Valley
650-604-0281
alison.j.hawkesbak@nasa.gov
Written by Elizabeth Landau
NASA’s Exoplanet Exploration Program
LUNAR HALO Taken by Jim Crawford on March 23, 2018 @ Limavady, Northern Ireland
I was out to photograph the Aurora as the horizon was cloudy I in turn took a series of photos of the vivid Lunar halo at 22:48
MANTENIMIENTO PLANETARIO CIUDAD DE ROSARIO - POR: GUSTAVO ARIAS /// FOTOS: ESMERALDA SOSA
.. revisando la AUREOLA del proyector del SOL ..
.. trabajando en el cableado ..
.. y revisando ESTRELLA VARIABLE MIRA CETI ..
ESTRELLA VARIABLE MIRA en proyector PLANETARIO ZEISS ( debajo a la derecha )
En constelación de CETUS ( LA BALLENA )
ESTRELLA MIRA desde ROSARIO - ARGENTINA
Foto: Esmeralda Sosa
.. la pasamos BOMBA Gus ! ..
Sunday, March 25, 2018
LUNAR HALO Taken by Noel Keating on March 23, 2018 @ Ballintra, Co Donegal , Ireland
Super Vivid Lunar Halo
What a vivid Lunar halo in the sky right now... with only a half moon the stars are shining brightly within the halo, and am really surprise the halo is so strong, as this is the type of halo you normally only get with a full moon.
What a sight.. never seen a halo like this before..
Captured from Ballintra, Co Donegal
ANNOUNCING NOVA CARINAE 2018 Image Credit & Copyright: A. Maury & J. Fabrega
How bright will Nova Carinae 2018 become? The new nova was discovered only last week. Although novas occur frequently throughout the universe, this nova, cataloged as ASASSN-18fv, is so unusually bright in the skies of Earth that it is now easily visible through binoculars in the southern hemisphere. Identified by the arrow, the nova occurs near the direction of the picturesque Carina Nebula. A nova is typically caused by a thermonuclear explosion on the surface of a white dwarf star that is accreting matter from a binary companion, although details of this outburst are currently unknown. Both professional and amateur astronomers will be monitoring this unusual stellar outburst in the coming weeks, looking to see how Nova Carinae 2018 evolves, including whether it becomes bright enough to be visible to the unaided eye.
40% MOON - 15 PANEL MOSAIC Taken by Giuseppe Petricca on March 23, 2018 @ Isle of Lewis, Eilean Siar, Scotland
40% illuminated, imaged between one rain shower and another, with acceptable seeing for the focal length used. 15 panel mosaic.
SkyWatcher BlackDiamond Newton 200/1000 - EQ5 Motor - Barlow 3x COMA Apo/Apla - ASI 120 MM - Baader Red Interference - 150/3000 frames - 15 Panel Mosaic - AS!2 - Registax 6.1 - Photoshop CC
CONJUNCTION Taken by Raffaele Esposito on March 20, 2018 @ Siding Spring AU
Mars in conjunction with M8 end M20
APO 106mm f/5.0 Astrograph
CCD: FLI Microline 11002
iTelescope Siding Spring AU
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