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M-1 The Crab Nebula


Colorful New Portrait Shows Energetic Details Embedded in Supernova Remnant In the summer of the year 1054 AD, Chinese astronomers saw a new "guest star," that appeared six times brighter than Venus. So bright in fact, it could be seen during the daytime for several months. Halfway around the world, Native Americans made pictographs of a crescent moon with the bright star nearby that some think may also have been a record of the supernova. This "guest star" was forgotten about until 700 years later with the advent of telescopes. Astronomers saw a tentacle-like nebula in the place of the vanished star and called it the Crab Nebula. Today we know it as the expanding gaseous remnant from a star that self-detonated as a supernova, briefly shining as brightly as 400 million suns. The explosion took place 6,500 light-years away. If the blast had instead happened 50 light-years away it would have irradiated Earth, wiping out most life forms. In the late 1960s astronomers discovered the crushed heart of the doomed star, an ultra-dense neutron star that is a dynamo of intense magnetic field and radiation energizing the nebula. Astronomers therefore need to study the Crab Nebula across a broad range of electromagnetic radiation, from X-rays to radio waves. This composite picture from five observatories captures the complexity of this tortured-looking supernova remnant. Release ID: STScI-2017-21

Take equal parts 1) supernova, 2) Hubble Space Telescope, and 3) Herschel infrared observatory.
Mix well. What do you get? Purple (and pink) majesty.

CRAB PULSAR (PSR B0531+21) sound.


Observation sequences of M1, showing the expansion of shock waves emanating from the Pulsar interacting
with the surrounding nebula. Charndra X-Rays (left), Hubble Visible light (right).
(Credit: NASA, JPL-Caltech)

As It Turns Out, We Really Are All Starstuff by JASON MAJOR on MARCH 23, 2015

This is a mosaic image, one of the largest ever taken by NASA's Hubble Space Telescope of the Crab Nebula, a six-light-year-wide expanding remnant of a star's supernova explosion. Japanese and Chinese astronomers recorded this violent event nearly 1,000 years ago in 1054, as did, almost certainly, Native Americans. The orange filaments are the tattered remains of the star and consist mostly of hydrogen. The rapidly spinning neutron star embedded in the center of the nebula is the dynamo powering the nebula's eerie interior bluish glow. The blue light comes from electrons whirling at nearly the speed of light around magnetic field lines from the neutron star. The neutron star, like a lighthouse, ejects twin beams of radiation that appear to pulse 30 times a second due to the neutron star's rotation.
A neutron star is the crushed ultra-dense core of the exploded star. The Crab Nebula derived its name from its appearance in a drawing made by Irish astronomer Lord Rosse in 1844, using a 36-inch telescope. When viewed by Hubble, as well as by large ground-based telescopes such as the European Southern Observatory's Very Large Telescope, the Crab Nebula takes on a more detailed appearance that yields clues into the spectacular demise of a star, 6,500 light-years away. The newly composed image was assembled from 24 individual Wide Field and Planetary Camera 2 exposures taken in October 1999, January 2000, and December 2000. The colors in the image indicate the different elements that were expelled during the explosion. Blue in the filaments in the outer part of the nebula represents neutral oxygen, green is singly-ionized sulfur, and red indicates doubly-ionized oxygen. Credit: NASA, ESA, J. Hester and A. Loll (Arizona State University)

Animation of the Crab Nebula,
  • starting with the shortest wavelengths (x-rays - blue)
  • and progressing through the visible spectrum (green)
  • to radio frequencies (beyond infrared).
The driving power here obviously looks like an electric motor.


Unlocking the secrets of the Crab Nebula

M1: The Crab Nebula Supernova Remnant (animation) from Adam Block on Vimeo.

This animation shows the expansion of the Crab Nebula between the years of 1999 and 2012. The 1999 picture was taken by ESO using the VLT. The more recent picture was taken at the Mount Lemmon SkyCenter using the 0.8m Schulman Telescope. Visit http://Skycenter.arizona.edu . You can participate in one of our stargazing programs and look through the same telescope to see the Crab Nebula with your own eyes!

M1 - Crab Nebula - Deep Sky Videos

The Crab Nebula - M1 in the Messier Catalogue - is a supernova remnant with an important pulsar at its centre. Here we look at it through Nik Szymanek's telescope and the professionals discuss what's going on in this "real-time explosion", unfolding in space on an epic timescale. Images thanks to Nasa, ESA, etc... And Adam Block Deep Sky Videos website: : Twitter Facebook: Flickr: More about the astronomers in our videos: Videos by Brady Haran Additional video editing by Stephen Slater

A Tour of the Crab Nebula

The year 2019 marks the 20th anniversary of the launch of NASA's Chandra X-ray Observatory into space. The Crab Nebula was one of the first objects that Chandra examined with its sharp X-ray vision, and it has been a frequent target of the telescope ever since. There are many reasons that the Crab Nebula is such a well-studied object. For example, it is one of a handful of cases where there is strong historical evidence for when the star exploded. Having this definitive timeline helps astronomers understand the details of the explosion and its aftermath. In the case of the Crab, observers in several countries reported the appearance of a "new star" in 1054 A.D. in the direction of the constellation Taurus. Much has been learned about the Crab in the centuries since. Today, astronomers know that the Crab Nebula is powered by a quickly spinning, highly magnetized neutron star called a pulsar, which was formed when a massive star ran out of its nuclear fuel and collapsed. The combination of rapid rotation and a strong magnetic field in the Crab generates an intense electromagnetic field that creates jets of matter and anti-matter moving away from both the north and south poles of the pulsar. Astronomers also see an intense wind flowing out in the equatorial direction. A new composite image adds to a scientific legacy, spanning nearly two decades, between Chandra and the Crab Nebula. We look forward to what the Crab Nebula will reveal next.

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Thanks to the Chandra Observatory

Stellar Evolution from the Chandra x-ray Observatory

Chandra fun facts

July 23, 1999 - Launch of Chandra X-ray Observatory

July 23, 2014 marks the 15th anniversary of the launch of the Chandra X-ray Observatory. Launched aboard the Space Shuttle Columbia from Kennedy Space Center on July 23, 1999, Chandra took its place among NASA’s “Great Observatories” and with its unique capability for producing sub-arcsecond X-ray images, it has revealed stunning discovery after stunning discovery. The Chandra program is managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama and is operated by the Smithsonian's Astrophysical Observatory in Cambridge, Massachusetts. Image credit: NASA Last Updated: July 30, 2015 Editor: Lee Mohon

July 23, 1999, Chandra X-ray Observatory Awaits Deployment

This 70mm frame shows the 50,162-pound Chandra X-ray Observatory before it was tilted upward for its release from the Space Shuttle Columbia's payload bay on July 23, 1999, just a few hours following the shuttle's arrival in Earth orbit. Chandra was spring-ejected from a cradle in the payload bay at 6:47 a.m. Central time. Commander Eileen Collins, the first female Shuttle Commander, maneuvered Columbia to a safe distance away from the telescope as an internal timer counted down to the first of a two-phase ignition of the solid-fuel Inertial Upper Stage (IUS). The IUS lit up as scheduled at 7:47 a.m., and a few minutes later, shut down as planned, sending Chandra on a highly elliptical orbit which was refined over the next few weeks by a series of firings of telescope thrusters, designed to place Chandra in an orbit about 6900 x 87,000 statute miles above the Earth.

In August 2015, Chandra will pass the 16th anniversary of another milestone in the mission – the release of the “First Light” images from the telescope. As of July 1st, 2015, Chandra has traveled over 17 billion miles while completing about 2,200 orbits of the Earth. Chandra has made over 14,000 observations over the last 16 years. The targets include objects as close as the Earth and as distant as black holes near the edge of the observable universe.

Image Credit: NASA/JSC

Artist illustration of the Chandra X-ray Observatory, the most sensitive X-ray telescope ever built. Credit: NASA/CXC/NGST

Chandra Movie Captures Expanding Debris from a Stellar Explosion

When the star that created this supernova remnant exploded in 1572, it was so bright that it was visible during the day.
And though he wasn’t the first or only person to observe this stellar spectacle, the Danish astronomer Tycho Brahe wrote a book
about his extensive observations of the event, gaining the honor of it being named after him. In modern times, astronomers have observed the debris field from this explosion − what is now known as Tycho’s supernova remnant −
using data from NASA’s Chandra X-ray Observatory, the NSF’s Karl G. Jansky Very Large Array (VLA) and many other telescopes.
Today, they know that the Tycho remnant was created by the explosion of a white dwarf star, making it part of the so-called
Type Ia class of supernovas used to track the expansion of the Universe. Since much of the material being flung out from the shattered star has been heated by shock waves − similar to sonic booms from supersonic planes −
passing through it, the remnant glows strongly in X-ray light. Astronomers have now used Chandra observations from 2000 through 2015 to create
the longest movie of the Tycho remnant’s X-ray evolution over time, using five different images. This shows the expansion from the explosion is still
continuing about 450 years later, as seen from Earth’s vantage point roughly 10,000 light years away. By combining the X-ray data with some 30 years of observations in radio waves with the VLA, astronomers have also produced a movie,
using three different images. Astronomers have used these X-ray and radio data to learn new things about this supernova and its remnant.
The researchers measured the speed of the blast wave at many different locations around the remnant. The large size of the remnant enables
this motion to be measured with relatively high precision. Although the remnant is approximately circular, there are clear differences in the speed
of the blast wave in different regions. The speed in the right and lower right directions is about twice as large as that in the left and the upper
left directions. This difference was also seen in earlier observations.
This range in speed of the blast wave’s outward motion is caused by differences in the density of gas surrounding the supernova remnant.
This causes an offset in position of the explosion site from the geometric center, determined by locating the center of the circular remnant.
The astronomers found that the size of the offset is about 10% of the remnant’s current radius, towards the upper left of the geometric center.
The team also found that the maximum speed of the blast wave is about 12 million miles per hour.
Offsets such as this between the explosion center and the geometric center could exist in other supernova remnants.
Understanding the location of the explosion center for Type Ia supernovas is important because it narrows the search region for a surviving
companion star. Any surviving companion star would help identify the trigger mechanism for the supernova, showing that the white dwarf pulled
material from the companion star until it reached a critical mass and exploded. The lack of a companion star would favor the other main trigger
mechanism, where two white dwarfs merge causing the critical mass to be exceeded, leaving no star behind.
The significant offset from the center of the explosion to the remnant’s geometric center is a relatively recent phenomenon.
For the first few hundred years of the remnant, the explosion’s shock was so powerful that the density of gas it was running into did not
affect its motion. The density discrepancy from the left side to the right has increased as the shock moved outwards,
causing the offset in position between the explosion center and the geometric center to grow with time.
So, if future X-ray astronomers, say 1,000 years from now, do the same observation, they should find a much larger offset.
A paper describing these results has been accepted for publication in The Astrophysical Journal Letters and is available online.
The authors are Brian Williams (NASA's Goddard Space Flight Center and Universities Space Research Association),
Laura Chomiuk (Michigan State University), John Hewitt (University of North Florida), John Blondin (North Carolina State University),
Kazimierz Borkowski (NCSU), Parviz Ghavamian (Towson University), Robert Petre (GSFC), and Stephen Reynolds (NCSU). NASA's Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program for NASA's Science Mission Directorate in Washington.
The Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, controls Chandra's science and flight operations.

Image credits: X-ray: NASA/CXC/GSFC/B. Williams et al; Optical: DSS; Radio: NSF/NRAO/VLA Read More from NASA's Chandra X-ray Observatory. For more Chandra images, multimedia and related materials, visit: Last Updated: May 13, 2016 Editor: Lee Mohon

Deepest X-ray Image Ever Reveals Black Hole Treasure Trove

Press Image and Caption An unparalleled image from NASA's Chandra X-ray Observatory gives astronomers the best look yet at the growth of black holes over billions of years beginning soon after the Big Bang. This is the deepest X-ray image ever obtained, collected with about 7 million seconds, or eleven and a half weeks, of Chandra observing time. The image comes from what is known as the Chandra Deep Field-South. The central region of the image contains the highest concentration of supermassive black holes ever seen, equivalent to about 5,000 objects that would fit into the area of the full Moon and about a billion over the entire sky. Credit: X-ray: NASA/CXC/Penn State/B.Luo et al. Images and a podcast about the findings are available at: For more Chandra images, multimedia and related materials, visit: Media contacts: Megan Watzke Chandra X-ray Center, Cambridge, Mass. 617-496-7998 Megan Watzke

Milky Way’s Black Hole Shows Signs of Increased Chatter

Three orbiting X-ray space telescopes have detected an increased rate of X-ray flares from the usually quiet giant black hole at the center
of our Milky Way galaxy after new long-term monitoring. Scientists are trying to learn whether this is normal behavior that was unnoticed due
to limited monitoring, or these flares are triggered by the recent close passage of a mysterious, dusty object. By combining information from long monitoring campaigns by NASA’s Chandra X-ray Observatory and ESA’s XMM-Newton, with observations by the
Swift satellite, astronomers were able to carefully trace the activity of the Milky Way’s supermassive black hole over the last 15 years.
The supermassive black hole, a.k.a. Sagittarius A*, weighs in at slightly more than 4 million times the mass of the Sun.
X-rays are produced by hot gas flowing toward the black hole. The new study reveals that Sagittarius A* (Sgr A* for short) has been producing one bright X-ray flare about every ten days.
However, within the past year, there has been a ten-fold increase in the rate of bright flares from Sgr A*, at about one every day.
This increase happened soon after the close approach to Sgr A* by a mysterious object called G2.
“For several years, we’ve been tracking the X-ray emission from Sgr A*. This includes also the close passage of this dusty object”
said Gabriele Ponti of the Max Planck Institute for Extraterrestrial Physics in Germany. “A year or so ago, we thought it had absolutely no effect
on Sgr A*, but our new data raise the possibility that that might not be the case."
Originally, astronomers thought G2 was an extended cloud of gas and dust. However, after passing close to Sgr A* in late 2013,
its appearance did not change much, apart from being slightly stretched by the gravity of the black hole.
This led to new theories that G2 was not simply a gas cloud, but instead a star swathed in an extended dusty cocoon.
“There isn’t universal agreement on what G2 is,” said Mark Morris of the University of California at Los Angeles.
“However, the fact that Sgr A* became more active not long after G2 passed by suggests that the matter coming off of G2 might have caused
an increase in the black hole’s feeding rate.” While the timing of G2’s passage with the surge in X-rays from Sgr A* is intriguing astronomers see other black holes that seem to behave
like Sgr A*. Therefore, it’s possible this increased chatter from Sgr A* may be a common trait among black holes and unrelated to G2.
For example, the increased X-ray activity could be due to a change in the strength of winds from nearby massive stars that are feeding material
to the black hole. “It’s too soon to say for sure, but we will be keeping X-ray eyes on Sgr A* in the coming months,” said co-author Barbara De Marco,
also of Max Planck. “Hopefully, new observations will tell us whether G2 is responsible for the changed behavior or if the new flaring is
just part of how the black hole behaves.”
The analysis included 150 Chandra and XMM-Newton observations pointed at the center of the Milky Way over the last 15 years,
extending from September 1999 to November 2014. An increase in the rate and brightness of bright flares from Sgr A* occurred after mid-2014,
several months after the closest approach of G2 to the huge black hole.
If the G2 explanation is correct, the spike in bright X-ray flares would be the first sign of excess material falling onto the black hole because
of the cloud’s close passage. Some gas would likely have been stripped off the cloud, and captured by the gravity of Sgr A*.
It then could have started interacting with hot material flowing towards the black hole, funneling more gas toward the black hole that could later
be consumed by Sgr A*.
A paper on these findings has been accepted by the Monthly Notices of the Royal Astronomical Society. A preprint is available online.
NASA's Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program for NASA's Science Mission Directorate in Washington.
The Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, controls Chandra's science and flight operations.
Image credit: NASA/CXC/MPE/G. Ponti et al.; Illustration: NASA/CXC/M. Weiss Read More from NASA's Chandra X-ray Observatory. For more Chandra images, multimedia and related materials, visit: Last Updated: Sept. 23, 2015 Editor: Lee Mohon

Chandra Spots Two Cosmic Heavy-Hitters at Once

Composite view of the collision between galaxy clusters Abell 3411 and Abell 3412 . Credit: X-ray: NASA/CXC/SAO/R. van Weeren et al./NAOJ/Subaru

Composite view of the collision between galaxy clusters Abell 3411 and Abell 3412 . Credit: X-ray: NASA/CXC/SAO/R. van Weeren et al./NAOJ/Subaru

Image of radio waves produce by the collision between Abell 3411 and Abell 3412. Credit: NASA/CXC/SAO/R. van Weeren et al. ts/m


A mysterious flash of X-rays has been discovered by NASA’s Chandra X-ray Observatory in the deepest X-ray image ever obtained. Credit: NASA/Chandra/Harvard

X-ray (left) and optical (right) images of the space around the X-ray source, made with Chandra and the Hubble Space Telescope, respectively. Credit: NASA/CXC/F. Bauer et al.

Still image of the X-ray source observed by Chandra, showing the captured flare up at bottom Credit: NASA/CXC/Pontifical Catholic Univ./F.Bauer et al.

Further Reading:Chandra, PennState


Still image of the X-ray source observed by Chandra, showing the captured flare up at bottom Credit: NASA/CXC/Pontifical Catholic Univ./F.Bauer et al.

The two brightest stars of the Centaurus constellation – (left) Alpha Centauri and (right) Beta Centauri. The faint red star in the center of the red circle is Proxima Centauri. Credit: Wikipedia Commons/Skatebiker

The respective habitable zones around Alpha Centauri A and B. Credit: Planetary Habitability Laboratory

A night in VLT and ALMA observatories (sound also recorded on location) from Jordi Busque on Vimeo.

The Very Large Telescope (VLT) consists of four individual telescopes, each with a primary mirror 8.2 m across and four movable Auxiliary Telescopes (ATs) of 1.8 m aperture. It is located on cerro Paranal (2635m), in northern Chile.

The Atacama Large Millimeter Array (ALMA) is the largest ground-based astronomical project consisting of 66 12-metre (39 ft), and 7-metre (23 ft) diameter radio telescopes. It is also the world's highest array of radio telescopes at 5,000 metres altitude in the Chajnantor plateau, northern Chile.

Images and sounds recorded on location by Jordi Busqué.

For more information, please visit www.jordibusque.com

As the only X-ray observatory capable of resolving Alpha Centauri A and B during its current close orbital approach, Chandra observed these two main stars every six months for the past thirteen years. These long-term measurements captured a full cycle of increases and decreases in X-ray activity, in much the same way that the Sun has an 11-year sunspot cycle.

At a distance of only 25 trillion miles, the Alpha Centauri star system is a prime target in humanity's search for life outside our Solar System. Astronomers would like to know what kind of environment exists around the two stars in Alpha Centauri that closely resemble our Sun. To learn about this, NASA's Chandra X-ray Observatory has been monitoring the Alpha Centauri system every six months for over a decade. Chandra is the only X-ray observatory capable of resolving the two Sun-like stars to determine which star is doing what. A new study indicates these two stars are likely not pummeling any orbiting planets with large amounts of X-ray radiation. This is promising news for the sustainability of life on any planets astronomers find around these two nearby stars in the future.

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