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APOD: 2019 January 19 - Total Lunar Eclipse at Moonset




The Moon slid through Earth's shadow on January 31, 2018 in a total lunar eclipse. In this time-lapse sequence of that eclipse from Portal, Arizona, USA, the partial eclipse starts with the Moon high in the western sky. The eclipse total phase lasted about 76 minutes, but totality ended after the dark, reddened Moon set below the horizon. The upcoming total lunar eclipse, on the night of January 20/21, will be better placed for skygazers across the Americas, though. There, all 62 minutes of the total phase, when the Moon is completely immersed in Earth's dark umbral shadow, will take place with the Moon above the horizon. Watch it if you can. The next total lunar eclipse visible from anywhere on planet Earth won't take place until May 26, 2021, and then the total eclipse will last a mere 15 minutes.

https://apod.nasa.gov/apod/ap190119.html

\#astronomy #picture #space #NASA #APOD

 
APOD: 2019 January 19 - Total Lunar Eclipse at Moonset




The Moon slid through Earth's shadow on January 31, 2018 in a total lunar eclipse. In this time-lapse sequence of that eclipse from Portal, Arizona, USA, the partial eclipse starts with the Moon high in the western sky. The eclipse total phase lasted about 76 minutes, but totality ended after the dark, reddened Moon set below the horizon. The upcoming total lunar eclipse, on the night of January 20/21, will be better placed for skygazers across the Americas, though. There, all 62 minutes of the total phase, when the Moon is completely immersed in Earth's dark umbral shadow, will take place with the Moon above the horizon. Watch it if you can. The next total lunar eclipse visible from anywhere on planet Earth won't take place until May 26, 2021, and then the total eclipse will last a mere 15 minutes.

https://apod.nasa.gov/apod/ap190119.html

\#astronomy #picture #space #NASA #APOD

 
#astronomy ( 5 photos )
Astrophotographer Creates Incredible Photo of the Solar System from His Backyard
Astrophotographer Creates Incredible Photo of the Solar System from His Backyard

 
#astronomy ( 5 photos )
Astrophotographer Creates Incredible Photo of the Solar System from His Backyard
Astrophotographer Creates Incredible Photo of the Solar System from His Backyard

 
#space #astronomy #universe #physics #astrophysics

 
APOD: 2019 January 13 - Tychos Supernova Remnant in Xray




What star created this huge puffball? What's pictured is the hot expanding nebula of Tycho's supernova remnant, the result of a stellar explosion first recorded over 400 years ago by the famous astronomer Tycho Brahe. The featured image is a composite of three X-ray colors taken by the orbiting Chandra X-ray Observatory. The expanding gas cloud is extremely hot, while slightly different expansion speeds have given the cloud a puffy appearance. Although the star that created SN 1572, is likely completely gone, a star dubbed Tycho G, too dim to be discerned here, is thought to be a companion. Finding progenitor remnants of Tycho's supernova is particularly important because the supernova is of Type Ia, an important rung in the distance ladder that calibrates the scale of the visible universe. The peak brightness of Type Ia supernovas is thought to be well understood, making them quite valuable in exploring the relationship between faintness and farness in the distant universe.

https://apod.nasa.gov/apod/ap190113.html

\#astronomy #picture #space #NASA #APOD

 
APOD: 2019 January 13 - Tychos Supernova Remnant in Xray




What star created this huge puffball? What's pictured is the hot expanding nebula of Tycho's supernova remnant, the result of a stellar explosion first recorded over 400 years ago by the famous astronomer Tycho Brahe. The featured image is a composite of three X-ray colors taken by the orbiting Chandra X-ray Observatory. The expanding gas cloud is extremely hot, while slightly different expansion speeds have given the cloud a puffy appearance. Although the star that created SN 1572, is likely completely gone, a star dubbed Tycho G, too dim to be discerned here, is thought to be a companion. Finding progenitor remnants of Tycho's supernova is particularly important because the supernova is of Type Ia, an important rung in the distance ladder that calibrates the scale of the visible universe. The peak brightness of Type Ia supernovas is thought to be well understood, making them quite valuable in exploring the relationship between faintness and farness in the distant universe.

https://apod.nasa.gov/apod/ap190113.html

\#astronomy #picture #space #NASA #APOD

 
They found an abundance of “hard” X-rays, which are 10 times more powerful than your average X-ray. This kind of signal is what some astronomers call a “hump,” and it’s usually associated with black holes. This signal strongly suggests that something inside the supernova is gobbling up material, as black holes often do. “So there is something alive in The Cow [the scientists' nickname for the object] that is producing these hard X-rays,” says Margutti. “That’s the crucial message from the observation.” She adds: “It’s something we’ve never seen in a transient before. It’s completely unprecedented. Margutti says The Cow got its nickname because it happened to be designated as AT2018cow as part of the team’s naming scheme.

Astronomers see a black hole or neutron star forming

#science #astronomy #blackhole

 
They found an abundance of “hard” X-rays, which are 10 times more powerful than your average X-ray. This kind of signal is what some astronomers call a “hump,” and it’s usually associated with black holes. This signal strongly suggests that something inside the supernova is gobbling up material, as black holes often do. “So there is something alive in The Cow [the scientists' nickname for the object] that is producing these hard X-rays,” says Margutti. “That’s the crucial message from the observation.” She adds: “It’s something we’ve never seen in a transient before. It’s completely unprecedented. Margutti says The Cow got its nickname because it happened to be designated as AT2018cow as part of the team’s naming scheme.

Astronomers see a black hole or neutron star forming

#science #astronomy #blackhole

 
APOD: 2019 January 11 - Partial Eclipse over Beijing




On January 6 the New Moon rose in silhouette with the Sun seen from northeastern Asia. Near maximum, the dramatic partial solar eclipse is captured in this telephoto view through hazy skies. In the foreground, the hill top Wanchun pavilion overlooking central Beijing's popular Forbidden City hosts eclipse-watching early morning risers. This was the first of five, three solar and two lunar, eclipses for 2019. Next up is a total lunar eclipse during this month's Full Perigee Moon. At night on January 21, that celestial shadow play will be visible from the hemisphere of planet Earth that includes the Americas, Europe, and western Africa.

https://apod.nasa.gov/apod/ap190111.html

\#astronomy #picture #space #NASA #APOD

 
APOD: 2019 January 11 - Partial Eclipse over Beijing




On January 6 the New Moon rose in silhouette with the Sun seen from northeastern Asia. Near maximum, the dramatic partial solar eclipse is captured in this telephoto view through hazy skies. In the foreground, the hill top Wanchun pavilion overlooking central Beijing's popular Forbidden City hosts eclipse-watching early morning risers. This was the first of five, three solar and two lunar, eclipses for 2019. Next up is a total lunar eclipse during this month's Full Perigee Moon. At night on January 21, that celestial shadow play will be visible from the hemisphere of planet Earth that includes the Americas, Europe, and western Africa.

https://apod.nasa.gov/apod/ap190111.html

\#astronomy #picture #space #NASA #APOD

 
"essentially crystal spheres in the sky"

Nature is so cool...


#space #astronomy #universe #physics #astrophysics

 
#space #astronomy #universe #physics #astrophysics

 
#space #astronomy #universe #physics #astrophysics

 

A fortunate catastrophe


To help my son in a school duty, I was reading about the genesis of the Moon. Fascinating.



(PD)

The Moon was formed 4500 million years ago, shortly after the formation of the solar system, in a gigantic collision: the Earth was hit by an object the size of Mars, that is to say approximately half of the terrestrial radius and 10% of its mass.

That early planet is named Theia, who according to Greek mythology was the mother of the moon goddess Selene. Theia orbited around the Sun in the same orbit as the Earth, but separated by a certain angle, near one of the Lagrange points known as L4 or L5.

Image/photo
(CC BY-SA 3.0, by Besnier.m)

The Lagrange points are stable points of the Earth-Sun system, where planetary garbage that does not fall on any of these celestial bodies can accumulate. Theia was formed at one of these points, from rocks and dust that did not fall to Earth during its genesis, and survived there.

Eventually, a passage near Venus destabilized Theia, who approached the Earth and catastrophically impacted it. The impact ripped off a piece of the Earth and horribly warmed the planet, vaporizing and/or melting much of its crust. The uprooted piece orbited very close to the Earth and began to accumulate some of the detached material, becoming the Moon.



(PD)

It is fascinating how much can we know about a collision that occurred 4500 million years ago, using only geological and selenological evidence.

* The Earth's axis of rotation and that of the lunar orbit are very similar, that is proof of the common origin of both bodies in a single impact.
  • We know the angle of the impact, because it can be deduced from the tilt of these axes with respect to the Earth's orbit, which incidentally is the cause of the seasons.
* We know the approximate radius of Theia, because that explains the amount of rotation (angular momentum) of the Earth-Moon system.
  • We know that the collision did not completely vaporize our planet, because the heavy elements (iron, nickel) remained on Earth, while very little of them can be found now on the Moon.
* For the collision not to completely vaporize the planet, the speed of the impact must have been relatively slow, less than 5km/s. That implies that Theia had an orbit very similar to that of the Earth. Such an orbit is only possible if it was near a Lagrange point.
  • However, we also know that the impact vaporized part of the Earth's crust, because there are almost no volatile elements on the Moon.
* A very interesting detail is that part of the vaporized material (mainly silicon) formed a hot atmosphere common to both bodies. The earth and lunar crust captured that ancient atmosphere, resulting in a similar composition (isotopic ratios).

Initially the Moon was much closer to the Earth. In the near face the terrestrial gravity was much stronger than in the distant one. This tidal force caused the heaviest face of the Moon to be always looking towards the Earth.

As the Moon cooled, the tidal force caused fractures on its surface, bringing out lava from its interior. These cracks were more frequent in the near face, where the attraction of the Earth was stronger. That's why that face is covered with maria: the gray spots on the Moon, which we call "seas", are actually outcrops of lava, already cold, caused by that process.



(CC BY-SA 3.0, by Peter Freiman)

Tidal forces deform both bodies, knead them. In this process, they dissipate energy, transforming it into heat. That process slows down the Moon. And as it slows down, it moves away from the Earth (because the third law of Kepler is satisfied). Eventually in the future, it will escape. Selene, Theia's daughter, will thus gain the freedom she never had since her tragic birth.

Image/photo
(PD)

As a species, we are fortunate to have the Moon so close to us. The Moon was the cause of many crucial facts of our existence
  • The gravity of the Moon causes the tides. In the distant past, tides left algae on beaches. These algae eventually evolved to colonize the continents, transforming into terrestrial plants.


    (CC BY-SA 3.0, by mabelcalabuig)
* Similarly, the tides left traps on the beaches, animals similar to shrimp and crabs. These evolved into terrestrial insects.
![]([url=https://www.publicdomainpictures.net/pictures/90000/nahled/crab-on-beach-14021078366TG.jpg]https://www.publicdomainpictures.net/pictures/90000/nahled/crab-on-beach-14021078366TG.jpg[/url])

(PD)
  • Finally, in more recent times the tides left fish on the beaches. These fish developed legs and the ability to breathe air... and here we are, the result of the evolution of terrestrial vertebrates.
    Image/photo
    (CC BY-SA 3.0, by Gianluca Polgar)
* Our prehistoric ancestors were curious. As they looked up at the sky they started to wonder what that brilliant disc was that illuminated the night, and why it had phases and eclipses. And trying to answer that question, they invented what we call science today.
![]([url=https://upload.wikimedia.org/wikipedia/en/6/62/Neanderthal-2D-MJC.jpg]https://upload.wikimedia.org/wikipedia/en/6/62/Neanderthal-2D-MJC.jpg[/url]) 
([CC BY-SA 3.0]([url=https://en.m.wikipedia.org/wiki/File:Neanderthal-2D-MJC.jpg]https://en.m.wikipedia.org/wiki/File:Neanderthal-2D-MJC.jpg[/url]), from Wikimedia)
  • Scientific progress will eventually lead us to colonize the solar system. To do this, we will almost certainly start with the Moon. Because of its proximity and low gravity, the Moon is ideal as a port, to receive and send ships, with supplies and settlers, to other planets.


    (PD)
Thus, human beings exist, evolve, and will hopefully survive, thanks to the existence of the Moon.

The apotheothic destruction of Theia was a fortunate catastrophe.

Post scriptum: disneylands


This is excellent news. There really are disneylands on the Moon, i.e. huge inhabitable underground caverns.

The Moon is a lucky accident. A celestial body close to the Earth, with abundant light and gravity high enough to be able to inhabit it comfortably, and at the same time low enough to be able to get to orbit without using rockets, with electromagnetic catapults. It is a natural port. A populated Moon would be our starting point for the rest of the solar system. Something very difficult to do directly from Earth.

But it is a natural accident, not a blessing from God. Populating it is not easy at all, more than anything because of its absence of magnetic field. Except when we see a compass, the rest of the time we don't think about the Earth's magnetic field. But it is a fundamental element that guarantees that we still alive.

The magnetic field deflects the solar wind towards the poles, causing the auroras borealis, and preventing that radiation from reaching us. Without a magnetic field, the solar wind radiation would reach the ground and be lethal. The onslaught of the solar wind is so strong that even on Mars, where it is much weaker, it dragged much of the atmosphere into space. I don't know if we could have evolved without the shield that the magnetic field gives us.



(PD)

The moon has no magnetic field. The solar wind reaches the ground. We could tolerate it for a few days. Even for a lifetime. But not for generations. That's why human settlements on the Moon must be underground (at least until we have gigantic superconducting magnets that can generate an artificial field).

It was always suspected that the Moon had underground caverns the size of cities. Science fiction author John Varley calls them disneylands in his stories of The Eight Worlds (which I recommend, read for example the excellent novels The Golden Globe or Steel Beach or the tales of Blue Champagne). This news is confirmation that they do exist, and that we won't have to dig the rock to build shelters. It is excellent.



(PD)

Once again, Theia's spectacular death insists on being a fortunate catastrophe.

#science #astronomy #moon




My posts (mostly in spanish) are published in

* Cave Canem (science, opinion)
* Literatops (literature, literary quotes)
* Diaspora*
* Mastodon
* SteemIt
* Reddit
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I can also be contacted in

* XMPP SeverianX
* Discord SeverianX#6874
* SteemChat SeverianX
* CuriousCat
* e-mail

 

A fortunate catastrophe


To help my son in a school duty, I was reading about the genesis of the Moon. Fascinating.



(PD)

The Moon was formed 4500 million years ago, shortly after the formation of the solar system, in a gigantic collision: the Earth was hit by an object the size of Mars, that is to say approximately half of the terrestrial radius and 10% of its mass.

That early planet is named Theia, who according to Greek mythology was the mother of the moon goddess Selene. Theia orbited around the Sun in the same orbit as the Earth, but separated by a certain angle, near one of the Lagrange points known as L4 or L5.

Image/photo
(CC BY-SA 3.0, by Besnier.m)

The Lagrange points are stable points of the Earth-Sun system, where planetary garbage that does not fall on any of these celestial bodies can accumulate. Theia was formed at one of these points, from rocks and dust that did not fall to Earth during its genesis, and survived there.

Eventually, a passage near Venus destabilized Theia, who approached the Earth and catastrophically impacted it. The impact ripped off a piece of the Earth and horribly warmed the planet, vaporizing and/or melting much of its crust. The uprooted piece orbited very close to the Earth and began to accumulate some of the detached material, becoming the Moon.



(PD)

It is fascinating how much can we know about a collision that occurred 4500 million years ago, using only geological and selenological evidence.

* The Earth's axis of rotation and that of the lunar orbit are very similar, that is proof of the common origin of both bodies in a single impact.
  • We know the angle of the impact, because it can be deduced from the tilt of these axes with respect to the Earth's orbit, which incidentally is the cause of the seasons.
* We know the approximate radius of Theia, because that explains the amount of rotation (angular momentum) of the Earth-Moon system.
  • We know that the collision did not completely vaporize our planet, because the heavy elements (iron, nickel) remained on Earth, while very little of them can be found now on the Moon.
* For the collision not to completely vaporize the planet, the speed of the impact must have been relatively slow, less than 5km/s. That implies that Theia had an orbit very similar to that of the Earth. Such an orbit is only possible if it was near a Lagrange point.
  • However, we also know that the impact vaporized part of the Earth's crust, because there are almost no volatile elements on the Moon.
* A very interesting detail is that part of the vaporized material (mainly silicon) formed a hot atmosphere common to both bodies. The earth and lunar crust captured that ancient atmosphere, resulting in a similar composition (isotopic ratios).

Initially the Moon was much closer to the Earth. In the near face the terrestrial gravity was much stronger than in the distant one. This tidal force caused the heaviest face of the Moon to be always looking towards the Earth.

As the Moon cooled, the tidal force caused fractures on its surface, bringing out lava from its interior. These cracks were more frequent in the near face, where the attraction of the Earth was stronger. That's why that face is covered with maria: the gray spots on the Moon, which we call "seas", are actually outcrops of lava, already cold, caused by that process.



(CC BY-SA 3.0, by Peter Freiman)

Tidal forces deform both bodies, knead them. In this process, they dissipate energy, transforming it into heat. That process slows down the Moon. And as it slows down, it moves away from the Earth (because the third law of Kepler is satisfied). Eventually in the future, it will escape. Selene, Theia's daughter, will thus gain the freedom she never had since her tragic birth.

Image/photo
(PD)

As a species, we are fortunate to have the Moon so close to us. The Moon was the cause of many crucial facts of our existence
  • The gravity of the Moon causes the tides. In the distant past, tides left algae on beaches. These algae eventually evolved to colonize the continents, transforming into terrestrial plants.


    (CC BY-SA 3.0, by mabelcalabuig)
* Similarly, the tides left traps on the beaches, animals similar to shrimp and crabs. These evolved into terrestrial insects.
![]([url=https://www.publicdomainpictures.net/pictures/90000/nahled/crab-on-beach-14021078366TG.jpg]https://www.publicdomainpictures.net/pictures/90000/nahled/crab-on-beach-14021078366TG.jpg[/url])

(PD)
  • Finally, in more recent times the tides left fish on the beaches. These fish developed legs and the ability to breathe air... and here we are, the result of the evolution of terrestrial vertebrates.
    Image/photo
    (CC BY-SA 3.0, by Gianluca Polgar)
* Our prehistoric ancestors were curious. As they looked up at the sky they started to wonder what that brilliant disc was that illuminated the night, and why it had phases and eclipses. And trying to answer that question, they invented what we call science today.
![]([url=https://upload.wikimedia.org/wikipedia/en/6/62/Neanderthal-2D-MJC.jpg]https://upload.wikimedia.org/wikipedia/en/6/62/Neanderthal-2D-MJC.jpg[/url]) 
([CC BY-SA 3.0]([url=https://en.m.wikipedia.org/wiki/File:Neanderthal-2D-MJC.jpg]https://en.m.wikipedia.org/wiki/File:Neanderthal-2D-MJC.jpg[/url]), from Wikimedia)
  • Scientific progress will eventually lead us to colonize the solar system. To do this, we will almost certainly start with the Moon. Because of its proximity and low gravity, the Moon is ideal as a port, to receive and send ships, with supplies and settlers, to other planets.


    (PD)
Thus, human beings exist, evolve, and will hopefully survive, thanks to the existence of the Moon.

The apotheothic destruction of Theia was a fortunate catastrophe.

Post scriptum: disneylands


This is excellent news. There really are disneylands on the Moon, i.e. huge inhabitable underground caverns.

The Moon is a lucky accident. A celestial body close to the Earth, with abundant light and gravity high enough to be able to inhabit it comfortably, and at the same time low enough to be able to get to orbit without using rockets, with electromagnetic catapults. It is a natural port. A populated Moon would be our starting point for the rest of the solar system. Something very difficult to do directly from Earth.

But it is a natural accident, not a blessing from God. Populating it is not easy at all, more than anything because of its absence of magnetic field. Except when we see a compass, the rest of the time we don't think about the Earth's magnetic field. But it is a fundamental element that guarantees that we still alive.

The magnetic field deflects the solar wind towards the poles, causing the auroras borealis, and preventing that radiation from reaching us. Without a magnetic field, the solar wind radiation would reach the ground and be lethal. The onslaught of the solar wind is so strong that even on Mars, where it is much weaker, it dragged much of the atmosphere into space. I don't know if we could have evolved without the shield that the magnetic field gives us.



(PD)

The moon has no magnetic field. The solar wind reaches the ground. We could tolerate it for a few days. Even for a lifetime. But not for generations. That's why human settlements on the Moon must be underground (at least until we have gigantic superconducting magnets that can generate an artificial field).

It was always suspected that the Moon had underground caverns the size of cities. Science fiction author John Varley calls them disneylands in his stories of The Eight Worlds (which I recommend, read for example the excellent novels The Golden Globe or Steel Beach or the tales of Blue Champagne). This news is confirmation that they do exist, and that we won't have to dig the rock to build shelters. It is excellent.



(PD)

Once again, Theia's spectacular death insists on being a fortunate catastrophe.

#science #astronomy #moon




My posts (mostly in spanish) are published in

* Cave Canem (science, opinion)
* Literatops (literature, literary quotes)
* Diaspora*
* Mastodon
* SteemIt
* Reddit
* Facebook
* Telegram
* Tumblr

I can also be contacted in

* XMPP SeverianX
* Discord SeverianX#6874
* SteemChat SeverianX
* CuriousCat
* e-mail

 
APOD: 2019 January 9 - Quadrantids




Named for a forgotten constellation, the Quadrantid Meteor Shower is an annual event for planet Earth's northern hemisphere skygazers It usually peaks briefly in the cold, early morning hours of January 4. The shower's radiant on the sky lies within the old, astronomically obsolete constellation Quadrans Muralis. That position is situated near the boundaries of the modern constellations Hercules, Bootes, and Draco. About 30 Quadrantid meteors can be counted in this skyscape composed of digital frames recorded in dark and moonless skies between 2:30am and local dawn. The shower's radiant is rising just to the right of the Canary Island of Tenerife's Teide volcano, and just below the familiar stars of the Big Dipper on the northern sky. A likely source of the dust stream that produces Quadrantid meteors was identified in 2003 as an asteroid. Look carefully and you can also spot a small, telltale greenish coma above the volcanic peak and near the top of the frame. That's the 2018 Christmas visitor to planet Earth's skies, Comet Wirtanen.

https://apod.nasa.gov/apod/ap190109.html

\#astronomy #picture #space #NASA #APOD

 
APOD: 2019 January 9 - Quadrantids




Named for a forgotten constellation, the Quadrantid Meteor Shower is an annual event for planet Earth's northern hemisphere skygazers It usually peaks briefly in the cold, early morning hours of January 4. The shower's radiant on the sky lies within the old, astronomically obsolete constellation Quadrans Muralis. That position is situated near the boundaries of the modern constellations Hercules, Bootes, and Draco. About 30 Quadrantid meteors can be counted in this skyscape composed of digital frames recorded in dark and moonless skies between 2:30am and local dawn. The shower's radiant is rising just to the right of the Canary Island of Tenerife's Teide volcano, and just below the familiar stars of the Big Dipper on the northern sky. A likely source of the dust stream that produces Quadrantid meteors was identified in 2003 as an asteroid. Look carefully and you can also spot a small, telltale greenish coma above the volcanic peak and near the top of the frame. That's the 2018 Christmas visitor to planet Earth's skies, Comet Wirtanen.

https://apod.nasa.gov/apod/ap190109.html

\#astronomy #picture #space #NASA #APOD

 

'One giant leap': #China's Chang'e 4 rover #JadeRabbit2 sets off on #moon #mission | World news | The Guardian


A giant leap for Chang-kind.

https://www.theguardian.com/world/2019/jan/04/china-change-4-moon-rover-jade-rabbit-2-sets-off

#Astronomy #ChangE4

 
Random image from the archives

APOD: 2013 October 3 - M106 Close Up




Close to the Great Bear (Ursa Major) and surrounded by the stars of the Hunting Dogs (Canes Venatici), this celestial wonder was discovered in 1781 by the metric French astronomer Pierre Mechain. Later, it was added to the catalog of his friend and colleague Charles Messier as M106. Modern deep telescopic views reveal it to be an island universe: a spiral galaxy around 30 thousand light-years across located only about 21 million light-years beyond the stars of the Milky Way. Along with prominent dust lanes and a bright central core, this colorful composite image highlights youthful blue star clusters and reddish stellar nurseries that trace the galaxy's spiral arms. The high resolution galaxy portrait is a mosaic of data from Hubble's sharp ACS camera combined with groundbased color image data. M106 (aka NGC 4258) is a nearby example of the Seyfert class of active galaxies, seen across the spectrum from radio to X-rays. Energetic active galaxies are powered by matter falling into a massive central black hole.

https://apod.nasa.gov/apod/ap131003.html

\#astronomy #picture #space #NASA #APOD

 
Random image from the archives

APOD: 2013 October 3 - M106 Close Up




Close to the Great Bear (Ursa Major) and surrounded by the stars of the Hunting Dogs (Canes Venatici), this celestial wonder was discovered in 1781 by the metric French astronomer Pierre Mechain. Later, it was added to the catalog of his friend and colleague Charles Messier as M106. Modern deep telescopic views reveal it to be an island universe: a spiral galaxy around 30 thousand light-years across located only about 21 million light-years beyond the stars of the Milky Way. Along with prominent dust lanes and a bright central core, this colorful composite image highlights youthful blue star clusters and reddish stellar nurseries that trace the galaxy's spiral arms. The high resolution galaxy portrait is a mosaic of data from Hubble's sharp ACS camera combined with groundbased color image data. M106 (aka NGC 4258) is a nearby example of the Seyfert class of active galaxies, seen across the spectrum from radio to X-rays. Energetic active galaxies are powered by matter falling into a massive central black hole.

https://apod.nasa.gov/apod/ap131003.html

\#astronomy #picture #space #NASA #APOD

 
Random image from the archives

APOD: January 21, 1996 - Mercury's Faults

Image/photo

The surface of the planet Mercury is not without fault. In this case, however, "fault" refers to unusual surface features that are the topic of much speculation. The above fault line is called Santa Maria Rupes, and runs through many prominent craters. The meandering feature is thought to be the result of huge forces of compression on Mercury's surface. Such rupes probably originate from large impacts and a general shrinking of Mercury's crust, which in turn causes parts of the crust to push above other parts.

https://apod.nasa.gov/apod/ap960121.html

\#astronomy #picture #space #NASA #APOD

 
Random image from the archives

APOD: January 21, 1996 - Mercury's Faults

Image/photo

The surface of the planet Mercury is not without fault. In this case, however, "fault" refers to unusual surface features that are the topic of much speculation. The above fault line is called Santa Maria Rupes, and runs through many prominent craters. The meandering feature is thought to be the result of huge forces of compression on Mercury's surface. Such rupes probably originate from large impacts and a general shrinking of Mercury's crust, which in turn causes parts of the crust to push above other parts.

https://apod.nasa.gov/apod/ap960121.html

\#astronomy #picture #space #NASA #APOD

 
APOD: 2018 December 28 - NGC 1365: Majestic Island Universe




Barred spiral galaxy NGC 1365 is truly a majestic island universe some 200,000 light-years across. Located a mere 60 million light-years away toward the chemical constellation Fornax, NGC 1365 is a dominant member of the well-studied Fornax galaxy cluster. This impressively sharp color image shows intense star forming regions at the ends of the bar and along the spiral arms, and details of dust lanes cutting across the galaxy's bright core. At the core lies a supermassive black hole. Astronomers think NGC 1365's prominent bar plays a crucial role in the galaxy's evolution, drawing gas and dust into a star-forming maelstrom and ultimately feeding material into the central black hole.

https://apod.nasa.gov/apod/ap181228.html

\#astronomy #picture #space #NASA #APOD

 
APOD: 2018 December 28 - NGC 1365: Majestic Island Universe




Barred spiral galaxy NGC 1365 is truly a majestic island universe some 200,000 light-years across. Located a mere 60 million light-years away toward the chemical constellation Fornax, NGC 1365 is a dominant member of the well-studied Fornax galaxy cluster. This impressively sharp color image shows intense star forming regions at the ends of the bar and along the spiral arms, and details of dust lanes cutting across the galaxy's bright core. At the core lies a supermassive black hole. Astronomers think NGC 1365's prominent bar plays a crucial role in the galaxy's evolution, drawing gas and dust into a star-forming maelstrom and ultimately feeding material into the central black hole.

https://apod.nasa.gov/apod/ap181228.html

\#astronomy #picture #space #NASA #APOD

 
APOD: 2018 December 28 - NGC 1365: Majestic Island Universe




Barred spiral galaxy NGC 1365 is truly a majestic island universe some 200,000 light-years across. Located a mere 60 million light-years away toward the chemical constellation Fornax, NGC 1365 is a dominant member of the well-studied Fornax galaxy cluster. This impressively sharp color image shows intense star forming regions at the ends of the bar and along the spiral arms, and details of dust lanes cutting across the galaxy's bright core. At the core lies a supermassive black hole. Astronomers think NGC 1365's prominent bar plays a crucial role in the galaxy's evolution, drawing gas and dust into a star-forming maelstrom and ultimately feeding material into the central black hole.

https://apod.nasa.gov/apod/ap181228.html

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APOD: 2018 December 26 - NGC 6357: The Lobster Nebula




Why is the Lobster Nebula forming some of the most massive stars known? No one is yet sure. Cataloged as NGC 6357, the Lobster Nebula houses the open star cluster Pismis 24 near its center -- a home to unusually bright and massive stars. The overall blue glow near the inner star forming region results from the emission of ionized hydrogen gas. The surrounding nebula, featured here, holds a complex tapestry of gas, dark dust, stars still forming, and newly born stars. The intricate patterns are caused by complex interactions between interstellar winds, radiation pressures, magnetic fields, and gravity. NGC 6357 spans about 400 light years and lies about 8,000 light years away toward the constellation of the Scorpion.

https://apod.nasa.gov/apod/ap181226.html

\#astronomy #picture #space #NASA #APOD

 
APOD: 2018 December 26 - NGC 6357: The Lobster Nebula




Why is the Lobster Nebula forming some of the most massive stars known? No one is yet sure. Cataloged as NGC 6357, the Lobster Nebula houses the open star cluster Pismis 24 near its center -- a home to unusually bright and massive stars. The overall blue glow near the inner star forming region results from the emission of ionized hydrogen gas. The surrounding nebula, featured here, holds a complex tapestry of gas, dark dust, stars still forming, and newly born stars. The intricate patterns are caused by complex interactions between interstellar winds, radiation pressures, magnetic fields, and gravity. NGC 6357 spans about 400 light years and lies about 8,000 light years away toward the constellation of the Scorpion.

https://apod.nasa.gov/apod/ap181226.html

\#astronomy #picture #space #NASA #APOD

 
APOD: 2018 December 26 - NGC 6357: The Lobster Nebula




Why is the Lobster Nebula forming some of the most massive stars known? No one is yet sure. Cataloged as NGC 6357, the Lobster Nebula houses the open star cluster Pismis 24 near its center -- a home to unusually bright and massive stars. The overall blue glow near the inner star forming region results from the emission of ionized hydrogen gas. The surrounding nebula, featured here, holds a complex tapestry of gas, dark dust, stars still forming, and newly born stars. The intricate patterns are caused by complex interactions between interstellar winds, radiation pressures, magnetic fields, and gravity. NGC 6357 spans about 400 light years and lies about 8,000 light years away toward the constellation of the Scorpion.

https://apod.nasa.gov/apod/ap181226.html

\#astronomy #picture #space #NASA #APOD