Rear-end Collisions Between High-speed Knots in Relativistic Jet

Produces shocks that accelerate particles, illuminating the colliding material 

The Hubble Space Telescope took this image of the core region of galaxy NGC 3862 with relativistic jet of material visible as line of light in the 3 o'clock position. Images to the right show knots of material outlined in blue, red and green moving along the jet over two decades. X marks the supermassive black hole. Credits: NASA/ESA/Hubble
The Hubble Space Telescope took this image of the core region of galaxy NGC 3862 with relativistic jet of material visible as line of light in the 3 o’clock position. Images to the right show knots of material outlined in blue, red and green moving along the jet over two decades. X marks the supermassive black hole.
Credits: NASA/ESA/Hubble

Space news (astrophysics: relativistic jets; shock collisions inside particle jets) – Observing plasma jet blasting from supermassive black hole in core of galaxy NGC 3862, 260 million light-years from Earth toward the constellation Leo in the rich galaxy cluster Abell 1367 –

Astronomers recently made an interesting discovery while studying data collected by the Hubble Space Telescope over two decades of observing the core of elliptical galaxy NGC 3862.  They were originally looking to create a time-lapse video of a relativistic jet blasting from the supermassive black hole thought to reside within its core. Instead, they discovered a rear-end collision between two separate high-speed waves of material ejected by a monster black hole whose mass astronomers have yet to measure. In this case, scientists believe the rear-end collision accelerated and heated particles which illuminated the colliding material for Hubble to see.

The relativistic jet erupting from the accretion disk of the supermassive black hole thought to reside at the core of galaxy NGC 3862 is one of the most studied and therefore best understood. It’s also one of the few active galaxies with jets observed in visible light. It appears to stream out of the accretion disk at speeds several times the speed of light, but this is just a visual illusion referred to as superluminal motion created by the combination of insanely fast velocities and our line of sight being almost on point. It forms a narrow beam hundreds of light-years in length that eventually begins to spread out like a cone, before forming clumps at around 1,000 light-years. Clumps scientists study looking for clues pointing to facts they can use to learn more about these plasma jets and the cosmos.

Astronomers have observed knots of material being ejected from dense stellar objects previously during the human journey to the beginning of space and time. This is one of the few times they have detected knots with an optical telescope thousands of light-years from a supermassive black hole. It’s the certainly the first time we have detected a rear-end collision between separately ejected knots in a relativistic jet. 

“Something like this has never been seen before in an extragalactic jet,” said Eileen Meyer of NASA’s Space Telescope Science Institute (STScI). “As the knots continue merging they will brighten further in the coming decades. This will allow us a very rare opportunity to see how the energy of the collision is dissipated into radiation.”

What would cause successive jets of material to achieve varying speeds? One theory involves the idea of material falling onto the supermassive black hole being superheated and ejected along its spin axis. Ejected material is constrained by the powerful magnetic fields surrounding the monster black hole into a narrow beam. If the flow of falling material isn’t perfectly smooth, knots are ejected in a string, rather than a continuous beam or steady hose.

It’s possible knots ejected later travel through a less dense interstellar medium, which would result in varying speeds. In this scenario, a knot launched after another knot would eventually catch up and rear-end it. 

Beyond learning knots of material ejected in plasma jets erupting from the accretion disk of a supermassive black hole sometimes rear-end each other, astronomers are interested in this second case of superluminal motion observed in jets hundreds, thousands of light-years from the source supermassive black hole. This indicates the jets are still moving at nearly the speed of light at distances rivaling the scale of the host galaxy and still contain tremendous energy. Understanding this could help astronomers determine more about the evolution of galaxies as the cosmos ages, including our own Milky Way.

Astronomers are also trying to figure out why galaxy NGC 3862 is one of the few they have detected jets in optical wavelengths? They haven’t been able to come up with any good theories on why some jets are detected in visible light and others aren’t. 

Work goes on

Work at the institute continues. Meyer is currently working on additional videos using Hubble images of other relativistic jets in nearby galaxies to try to detect superluminal motion. This is only possible due to the longevity of the Hubble Space Telescope and ingenuity of engineers and scientists from NASA and the ESA. Hopefully, they could discover more clues to answer these questions and other mysteries gnawing at the corner of my mind.

Watch this video made by Eileen Meyer of the Space Telescope Science Institute (STScI) in Baltimore, Maryland using archival data from two decades of Hubble Space Telescope observations of galaxy NGC 3862.

Read about magnetic lines of force NASA astronomers viewed emanating from a supermassive black hole 900 million light-years from Earth.

Read and learn more about how astronomers study the formation of stars in the Milky Way.

Read about a runaway star discovered traveling across the Tarantula Nebula.

Take the space voyage of NASA.

Read and learn more about relativistic jets here.

Learn more about the discoveries made by the ESA.

Learn more about galaxy NGC 3862 here.

Learn what astronomers have discovered about supermassive black holes.

Discover and learn more about superluminal motion here.

Discover NASA’s Space Telescope Science Institute (STScI).

Take the space journey of the Hubble Space Telescope here.

 

 

 

 

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Small Region of Sky Source of Mysterious, Energetic Blasts

Astronomers have identified source as a supermassive, unknown star cluster containing some of the most massive stars in the Milky Way 

Hidden within the region inset in the small square lie some of the rarest, most massive stars in the galaxy.
Hidden within the region inset in the small square lie some of the rarest, most massive stars in the galaxy. More than a dozen red supergiant stars. Credit: NASA/ESA/STScI

Space news (unknown X-ray and gamma-ray sources) – 2/3 of the way to the core of the Milky Way or 18,900 light-years (5,800 parsecs) from Earth toward the constellation Scutum in the Bermuda Triangle of the Milky Way – 

For years, astronomers studied a small region of the sky called the Bermuda Triangle known for mysterious, highly energetic blasts of X-rays and gamma rays looking for clues to the source. The identity of the source was finally determined around 2005 as an unknown, hefty star cluster containing some of the rarest and most massive stars in the Milky Way. More than a dozen red supergiant stars, supermassive stars that are destroyed when a star goes supernova, within a million years time.  

This color composite image compiled by the Spitzer Space Telescope highlights the colors of the cosmos. Credit: NASA/ESA/STScI
This color composite image compiled by the Spitzer Space Telescope highlights the dazzling color palette of the cosmos. Credit: NASA/ESA/STScI

Astronomers detected 14 gigantic, red supergiant stars bloated to beyond 100 times their original size hidden within a star cluster estimated to be over 20 times the average size. Their outer envelopes of hydrogen bloated to beyond bursting, these behemoth stars are destined to end their days in one of the most energetic events in the cosmos a supernova. Destined to spread the elements of creation throughout the galaxy in a titanic explosion more energetic than the output of the entire Milky Way. 

“Only the most massive clusters can have lots of red supergiants because they are the only clusters capable of making behemoth stars,” explains Don Figer led scientists for the study. “They are good signposts that allow astronomers to predict the mass of the cluster. This observation also is a rare chance to study huge stars just before they explode. Normally, we don’t get to see stars before they pop off.” 

This very colorful artist's impression of the stars within this unknown star cluster. CreditNASA/ESA/STScI
This very colorful artist’s impression of the 14 red supergiant stars within this unknown star cluster. CreditNASA/ESA/STScI

What’s next for the team?

Red supergiant stars were indeed rare during the human journey to the beginning of space and time. Only about 200 such titanic stars have been identified among the hundreds of millions detected in the Milky Way. Finding 14 of these behemoth stars relatively close to Earth is an opportunity for astronomers to study their life cycle in greater detail. An opportunity Figer and his team at the Space Telescope Science Institute (STScI) in Baltimore plan on taking full advantage of during the years ahead. 

At the same time, Figer and his team of space scientists plan on studying an additional 130 supermassive star cluster candidates from the newly found clusters compiled in the Two Micron All Sky Survey catalog. “We can only see a small part of our galaxy in visible light because a dusty veil covers most of our galaxy,” Figer said. “I know there are other massive clusters in the Milky Way that we can’t see because of the dust. My goal is to find them using infrared light, which penetrates the dusty veil.” 

“Mysterious X-ray and gamma ray source explained!” 

“Now, we search for new cosmic mysteries to unveil!”

Take the space journey of NASA

Learn more about the Milky Way here

Discover the constellation Scutum

Learn more about the Space Telescope Science Institute here

Discover things about star clusters here

Take the space voyage of the Hubble Space Telescope here.

Learn more about red supergiant stars

Read about the Nuclear Star Cluster, the Milky Way’s densest star cluster.

Learn more about the giant star blowing a huge bubble of gas.

Read about astronomers discovering superstar binary systems like Eta Carinae are more common than first thought.

Concerned Earthlings Planning on Moving to an Exoplanet in the Far Future

No need not worry, according to planetary scientists, the majority of potential cradles for a new human Genesis have yet to be born

Mars is one of the newest location humans plan on visiting and possibly inhabiting in the near future. This spot looks promising, but getting the work crew to this spot is a killer. Realtors of the future will have to work on this one a bit. Image credit: NASA
Mars is one of the newest location humans plan on visiting and possibly inhabiting in the near future. This spot looks promising, but getting the work crew to this spot is a killer. Realtors of the future will have to work on this one a bit. Image credit: NASA

Space news (October 24, 2015) – The journey to Mars –

Earthlings thinking about moving to Mars, or another planet, with the first spacecraft leaving, can breathe a sigh of relief. Peter Behroozi and Molly Peeples of NASA’s Space Telescope Science Institute (STScI) have completed a study of the percentage of Earth-like planets created during the life of the universe, so far, and according to estimates, the majority of Earth-like planets have yet to be born. 

“Our main motivation was understanding the Earth’s place in the context of the rest of the universe,” said study author Peter Behroozi of the Space Telescope Science Institute (STScI) in Baltimore, Maryland, “Compared to all the planets that will ever form in the universe, the Earth is actually quite early.”

“There is enough remaining material [after the big bang] to produce even more planets in the future, in the Milky Way and beyond,” added co-investigator Molly Peeples of STScI.

The diversity of exoplanets is large — more than 800 planets outside the Solar System have been found to date, with thousands more waiting to be confirmed. Detection methods in this field are steadily and quickly increasing — meaning that many more exoplanets will undoubtedly be discovered in the months and years to come. This planet looks promising, but is going to be a problem reaching with current technology. Image credit IAU
The diversity of exoplanets is large — more than 800 planets outside the Solar System have been found to date, with thousands more waiting to be confirmed. Detection methods in this field are steadily and quickly increasing — meaning that many more exoplanets will undoubtedly be discovered in the months and years to come.
This planet looks promising but is going to be a problem reaching with current technology.
Image credit IAU

By Earth-like we mean an exoplanet the right distance from its parent star for water to exist in liquid form and the Genesis of life to take place. Earth is the only planet we know life exists on, but considering estimates of the size of the cosmos, one would certainly expect life has popped its head up somewhere else. If their estimates of the amount of gas left over for the formation of new stars is correct, the Milky Way and universe will be making new stars for a very long time. 

There’s still lots of time to invent, or order on the uni-net (Universal Internet), a faster-than-light spacecraft to help in your search for a new home. Current estimates indicate there are at least 1 billion Earth-sized planets in the Milky Way. How many are suitable homes you can live on? Maybe by the time you get the spacecraft you need, they’ll have a better estimate of exactly how many are Earth-like. 

You still have time to prepare!

Unless you’re a time traveler from the future, you have time to prepare, and this team of intrepid astronomers has time to refine their estimate. Hopefully, by then, we’ll be permanently connected to the uni-net, and you can just look online for the best property on an exoplanet far, far away.

You can learn more about NASA’s mandate to travel to the stars here.

You can discover the Hubble Space Telescope.

Learn more about the Space Telescope Science Institute here.

Learn more and become part of Planetary Resources Inc’s plans to mine an asteroid in the near future.

Read about astronomers search for planets with the building blocks of life.

Read about the detection of the first Earth-sized planet.

 

Star Clusters of Unimaginable Size Exist in the Universe

Understanding how large star clusters form could tell us more about star formation when the universe was young

The Tarantula nebula in full glory
The Tarantula nebula in full glory

Astronomers news (2013-10-14) – Tonight we’ll journey to the truly titanic 30 Doradus nebula (also called the Tarantula nebula), 170 light-years away in the Large Magellanic Cloud, aboard the Hubble Space Telescope. The Large Magellanic Cloud is a smaller satellite galaxy to the Milky Way, where astronomers recently discovered something they suspected about the formation of larger star clusters.

Using Hubble’s Wide Field Camera 3, we’ll be able to look at images of the Tarantula nebula filled with startling reds, greens and blues, which indicates to astronomers the elemental composition of the  stars in the region. Blue light is from the hottest, most massive stars astronomers have found to date. Red light is from fluorescing hydrogen gas, while green light is the glow of oxygen.

Every element on the periodic table gives off light with a specific signature upon fluorescing. Scientists use this knowledge to analyze the light reaching Hubble’s Wide Field Camera 3 from the Tarantula nebula to determine the elemental composition of the stars in the region .They hope to use this knowledge to answer questions they have concerning star formation when the universe was still in its infancy.

30 Doradus is full of red, blue and yellow light
30 Doradus is full of red, blue and green light

NASA astronomers see something different going on in 30 Doradus

We’ll specifically journey to a region of the 30 Doradus nebula where astronomers recently discovered a pair of star clusters which they first thought was a single star cluster, is in fact a pair of star clusters in the initial stages of merging into a larger star cluster. Astronomers now think the merging of star clusters could help explain the abundance of large star clusters throughout the visible universe.

Lead scientist Elena Sabbi of the Space Telescope Science Institute in Baltimore, Maryland and her team first started looking at the region to find runaway stars. Runaway stars are fast-moving stars that have been kicked out of the stellar nursery where they first formed. Astronomers found the region surrounding 30 Doradus has a large number of runaway stars, which according to current star formation theories could not have formed at their present location. Astronomers now believe the runaway stars outside 30 Doradus could have been ejected out of the region at high speed due to dynamic interactions with other stellar bodies as the two star clusters merge into one larger star cluster.

This image of 30 Doradus makes one feel small
This image of 30 Doradus makes one feel small

Astrophysicists and astronomers started looking for clues

The first clue to the true nature of the event astronomers were viewing was the fact that parts of the star cluster varied in age by about 1 million years. Upon further study the team noticed the distribution of low-mass stars detected by Hubble were not spherical in shape as astronomers expected, but resembled the elongated shape of two merging galaxies. Now astronomers are studying this region of space and time to find clues to help them understand the way larger star clusters are formed in the universe. They also hope this discovery will help determine interesting and enlightening facts concerning the formation of star clusters when the universe was still young.

Astronomers are also looking further at this region of space and time to find other star clusters in the process of merging in the 30 Doradus nebula. They plan on using the ability of the James Webb Space Telescope to detect infrared light , once it comes on line, to take a closer look at areas within the Tarantula nebula where they think stars hidden within cocoons of dust are blocked from the view of telescopes and instruments detecting visible light.

Read about NASA’s Messenger spacecraft and its mission to Mercury

Have you heard about the recent meteorite that exploded near the Ural Mountains

Read about the supernova astronomers are studying looking for a black hole they think was created during the explosion

Journey into the Heart of the Beehive

Bright stars of red and blue highlight the Beehive or Omega Centauri cluster
The bottom photo reminds many of bees moving around in a hive

 The Hubble Space Telescope takes the human “Journey to the Beginning of Space and Time” into the beehive

Astronomy News – We join the human “Journey to the Beginning of Space and Time” as it boards the Hubble Space Telescope to travel 15,800 light years (~ 4850 parsecs) into Centaurus the Centaur to globular cluster Omega Centauri to peer into the beehive and look at individual stars. The beehive as it’s called was first noted by early star-gazer Ptolemy 2,000 years ago, both the largest and brightest globular cluster orbiting the Milky Way, the beehive is about 12 billion years old. Ptolemy didn’t have the Hubble Space Telescope to view Omega Centauri, so in his writings, he refers to the beehive as a single star. In reality, the beehive, or Omega Centauri, is a tightly packed group of about 10 million stars held together by gravity and orbiting a central gravitation mass, of some kind. In fact, the stars in the beehive are on average only about 0.1 light years apart, so close together that astronomers had to use the powerful vision of the Hubble Space Telescope to resolve individual stars.
The view from the Hubble Space Telescope

Hubble gives us the best view of the universe we have ever had

The Hubble Space Telescope’s vision is sharp enough astronomers used the images they have collected over a four-year period of viewing globular cluster Omega Centauri to precisely measure the relative motions of over 100,000 individual stars in the beehive. In an effort to gain insight into the evolution and life cycle of tight groups of stars formed in the early universe, and try to determine if there’s, in fact, an intermediate mass black hole hidden in the beehive. This study was conducted over a four-year period by Jay Anderson and Roeland van der Marel of the Space Telescope Science Institute using Hubble’s Advanced Camera for Surveys and high-speed, sophisticated computer programs to measure the relative motions of individual stars in the beehive.

On a clear night in the southern equatorial region of the night sky, it’s even possible to view the 3.5 magnitude beehive with the naked eye. Globular cluster Omega Centauri will appear as a fuzzy star that early astronomers believed was a single star. Use astronomical binoculars as your time-machine-to-the-stars, or a telescope, and the view becomes a wonder to behold as wide across in your viewfinder as the Full Moon. Using an 8-inch time-machine-to-the-stars you’ll view about 1,000 stars, each a faint pinprick of light, and you should notice that the beehive isn’t completely circular. Globular cluster Omega Centauri, in fact, rotates at a pretty fast speed around its central gravitational mass and astronomers believe this is one reason it’s less than circular.

Check out my latest astronomy website at http://astronomytonight.yolasite.com/.