Chandra X-rays a giant hand in space

A cosmic hand
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken by the Chandra X-ray Observatory, with data from the orbiting IXPE producing the lines that indicate the orientation of the magnetic field lines.

The image was part of research studying what the scientists call Pulsar Wind Nebulae (PWNe).

[E]arly-on when the new-born pulsar is still deep in its parent supernova remnant, or at late times after it has escaped to the relatively uniform interstellar medium, the pulsar wind is often uniform around the pulsar spin or velocity axis. In projection on the sky such structures have bilateral symmetry, that is, the two halves mirror each other. This makes them look (vaguely) like animals. This has led to many PWNe collecting animal monikers (‘The Mouse’, ‘The Dragonfly’, ‘The Rabbit’ – we are guilty of some of these…).

In between these early and late phases, the story is often more complex and the PWN interaction with the supernova shock wave leads to complicated morphologies. One of the prime examples is the PWN in the supernova remnant RCW 89 (also known as MSH 15-5(2)). Here the complex interactions form the PWN into the `Cosmic Hand’. Wanting to map the magnetic fields which structure this hand, the IXPE team took a long hard stare at MSH 15-5(2) and its central pulsar.

The scientists admit that the match between IXPE’s data and the structure of the hand is not really a surprise, but confirming the match was necessary if they are ever going to figure out the fundamental laws that govern magnetic fields, laws that presently are not well understood, at all.

New data better maps the supernova remnant SN1006

SN1006, as seen in X-rays
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Using data from both the Chandra X-ray Observatory and the Imaging X-ray Polarimetry Explorer (IXPE), scientists have now better mapped the magnetic field and the remnant from the supernova that occurred in 1006 AD.

The false color image to the right shows this data. From the caption:

The red, green, and blue elements reflect low, medium, and high energy X-rays, respectively, as detected by Chandra. The IXPE data, which measure the polarization of the X-ray light, is show in purple in the upper left corner, with the addition of lines representing the outward movement of the remnant’s magnetic field.

From the press release:

Researchers say the results demonstrate a connection between the magnetic fields and the remnant’s high-energy particle outflow. The magnetic fields in SN 1006’s shell are somewhat disorganized, per IXPE’s findings, yet still have a preferred orientation. As the shock wave from the original explosion passes through the surrounding gas, the magnetic fields become aligned with the shock wave’s motion. Charged particles are trapped by the magnetic fields around the original point of the blast, where they quickly receive bursts of acceleration. Those speeding high-energy particles, in turn, transfer energy to keep the magnetic fields strong and turbulent.

At present scientists really do not understand the behavior of stellar-sized magnetic fields. It is very complex, involving three dimensional movements that are hard to measure, as well as electromagnetic processes that are not well understood. While this new data doesn’t provide an explanation, it does tell us better what is actually happening. The theories will follow.

NASA: Budget cuts to Hubble/Chandra under consideration

In what is likely a negotiating ploy with Congress to prevent any budget cuts at all at NASA, the agency revealed late last week that it is considering cutting the budgets to both the Hubble and Chandra space telescopes in order to meet proposed budget limits.

In an Oct. 13 presentation to the National Academies’ Committee on Astronomy and Astrophysics, Mark Clampin, director of NASA’s astrophysics division, said he was studying unspecified cuts in the operating budgets of the Chandra X-Ray Observatory and Hubble Space Telescope to preserve funding for other priorities in the division.

The potential cuts, he said, are driven by the expectation that his division will not receive the full request of nearly $1.56 billion for fiscal year (FY) 2024 because of legislation passed in June that caps non-defense discretionary spending for 2024 at 2023 levels, with only a 1% increase for 2025. “We’re working with the expectation that FY24 budgets stay at the ’23 levels,” he said. “That means that we have decided to reduce the budget for missions in extended operations, and that is Chandra and Hubble.”

That he provided no details suggests this is merely a lobbying tactic. Essentially he is saying to Congress, “If you don’t give me more money I will be forced to shut down our most popular programs. That won’t sit well with your constituents!”

That the House in its appropriations to NASA for 2024 did not cut the agency’s budget significantly also suggests this is mere lobbying. There should be no reason to trim Hubble or Chandra, which are two of the agency’s most successful projects, unless the cost overruns on SLS/Orion and the Mars Sample Return missions are forcing NASA to grab money from other programs. If so, that problem is not Congress’s, but NASA’s. The agency should reconsider those failed projects in order to keep what works working.

Chandra: New X-ray composite images of galaxies and supernovae remnants

Chandra image
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The science team for the Chandra X-Ray observatory today released five new composite images of two galaxies, two supernovae remnants, and the center of the Milky Way, combining data from multiple telescopes looking in radio, infrared, optical, and X-ray wavelengths.

The image to the right, reduced and sharpened to post here, is one of those pictures. From the press release:

As the galaxy moves through space at 1.5 million miles per hour, it leaves not one — but two — tails behind it. These tails trailing after ESO 137-001 are made of superheated gas that Chandra detects in X-rays (blue). ESO’s Very Large Telescope shows light from hydrogen atoms (red), which have been added to the image along with optical and infrared data from Hubble (orange and cyan).

The inset shows just the Hubble optical image, reduced by about 50%, to get a clearer sense of the galaxy itself. It appears to be a jelly-fish galaxy, flying through space at right angles to its plane and with tendrils of stars trailing off below.

The other four images are as interesting. The full set, including separate images in the individual wavelengths prior to combination, can be found here.

Webb and Chandra take composite X-ray/infrared images of four famous objects

Composite Chandra/Webb image of M16
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Astronomers have now used the Chandra X-ray Observatory and Webb Space Telescope (working in the infrared) to produce spectacular composite false-color X-ray/infrared images of four famous heavenly objects.

To the right is the composite taken of the Eagle Nebula, also known as Messier 16. It was also dubbed the Pillars of Creation when it was one of the first Hubble images taken after the telescope’s mirror focus was fixed in 1993. From the caption:

The Webb image shows the dark columns of gas and dust shrouding the few remaining fledgling stars just being formed. The Chandra sources, which look like dots, are young stars that give off copious amounts of X-rays. (X-ray: red, blue; infrared: red, green, blue)

The other images include star cluster NGC 346 in a nearby galaxy, the spiral galaxy NGC 1672, and the face-on spiral galaxy Messier 74.

Astronomers discover more than 800 new supermassive black holes

Using archival data from both the orbiting Chandra X-Ray telescope and the ground-based Sloan Digital Sky Survey telescope (SDSS), astronomers have discovered more than 800 new supermassive black holes hidden in the center of galaxies.

By systematically combing through the deep Chandra Source Catalog and comparing to SDSS optical data, the researchers identified 817 XBONG candidates, more than ten times the number known before Chandra was in operation. Chandra’s sharp images, matching the quality of those from SDSS, and the large amount of data in the Chandra Source Catalog made it possible to detect this many XBONG candidates. Further study revealed that about half of these XBONGs represent a population of previously hidden black holes.

The key to this discovery is the use of telescopes observing in different wavelengths, X-rays with Chandra and optical with SDSS. Combined the data showed evidence of the hidden supermassive black holes.

Chandra takes an X-ray look at early Webb infrared observations

Chandra's X-ray vision of the Cartwheel Galaxy
Chandra’s X-ray view of the Cartwheel Galaxy

Webb's view of the Cartwheel Galaxy
Webb’s infrared view of the Cartwheel Galaxy
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Hubble's optical view of the Cartwheel Galaxy
Hubble’s optical view of the Cartwheel Galaxy. Click for original image.

Astronomers have now taken X-ray images using the orbital Chandra X-ray Observatory of four of the first Webb Space Telescope observations. The four targets were the Cartwheel Galaxy, Stephan’s Quintet, galaxy cluster SMACS 0723.3–7327, and the Carina Nebula.

The three images to the right illustrate the importance of studying astronomy across the entire electromagnetic spectrum. Each shows the Cartwheel Galaxy as seen by three of the world’s most important space-based telescopes, each looking at the galaxy in a different wavelength.

The top picture is Chandra’s new X-ray observations. As the press release notes,

Chandra data generally show higher-energy phenomena (like superheated gas and the remnants of exploded stars) than Webb’s infrared view. … X-rays seen by Chandra (blue and purple) come from superheated gas, individual exploded stars, and neutron stars and black holes pulling material from companion stars.

The middle picture was produced by Webb, shortly after the start of its science operations. It looks at the galaxy in the infrared.

In this near- and mid-infrared composite image, MIRI data are colored red while NIRCam data are colored blue, orange, and yellow. Amidst the red swirls of dust, there are many individual blue dots, which represent individual stars or pockets of star formation. NIRCam also defines the difference between the older star populations and dense dust in the core and the younger star populations outside of it.

The bottom picture was taken by the Hubble Space Telescope in 1995. I have rotated the image to match the others. It looks at the galaxy in optical wavelengths, the wavelengths that our eyes perceive.

Note how bright the central galactic region is in the infrared and optical, but is invisible in X-rays. Chandra is telling us that all the most active regions in the Cartwheel are located in that outer ring, not in its center.

Chandra’s camera remains in safe mode

Though engineers have improvised a work-around that has allowed most of instruments on the Chandra X-Ray observatory to resume science operations, the power supply problem in the telescope’s high resolution camera (HRC) that occurred on February 9th remains unresolved, leaving that camera in safe mode.

The Chandra science instrument and engineering teams continue to analyze the cause of the HRC power supply issue, as well as potential approaches to enable the HRC again. The spacecraft is otherwise healthy and operating normally.

Chandra has been flying now for more than two decades, well past its original mission. For it to begin to have these problems is not surprising, though it will be a great tragedy if it fails just as the James Webb Space Telescope is about to go operational. Ideally astronomers want data from both, as well as Hubble, to cover a wide swath of the electromagnetic spectrum, from the optical to the infrared to X-rays.

Chandra in safe mode

The Chandra X-ray Observatory last week experienced a loss of power that caused engineers to put the science instruments on the space telescope into safe mode while they investigate the problem.

No further information is presently available.

Chandra has been in orbit since 1999, and is now on an extended mission through 2025. It would be a great tragedy if it failed now, just as the infrared Webb telescope is about to begin operations. The two space telescopes are complementary.

Chandra captures black hole outburst over eight months

Four-frame movie of black hole outburst

Astronomers using the Chandra X-ray space telescope have documented the motion of two blobs moving away from a stellar-mass black hole over a period of eight months, producing a four-frame movie from their images and estimating the speed of those blobs to be 80% that of the speed of light.

The gif animation to the right shows that short movie.

The black hole and its companion star make up a system called MAXI J1820+070, located in our Galaxy about 10,000 light years from Earth. The black hole in MAXI J1820+070 has a mass about eight times that of the Sun, identifying it as a so-called stellar-mass black hole, formed by the destruction of a massive star. (This is in contrast to supermassive black holes that contain millions or billions of times the Sun’s mass.)

The companion star orbiting the black hole has about half the mass of the Sun. The black hole’s strong gravity pulls material away from the companion star into an X-ray emitting disk surrounding the black hole.

While some of the hot gas in the disk will cross the “event horizon” (the point of no return) and fall into the black hole, some of it is instead blasted away from the black hole in a pair of short beams of material, or jets. These jets are pointed in opposite directions, launched from outside the event horizon along magnetic field lines. The new footage of this black hole’s behavior is based on four observations obtained with Chandra in November 2018 and February, May, and June of 2019, and reported in a paper led by Mathilde Espinasse of the Université de Paris.

Hubble has produced similar movies of the activity around the Crab Nebula. Sadly, we don’t have enough space telescopes like these in orbit to monitor such objects more frequently and thus photograph their behavior more completely. If we did we’d be able to get a much better understanding of their ongoing activity. We would also be able to produce more movies such as this, with much higher resolution and more continuous coverage.

Chandra goes into safe mode

When it rains it pours: The Chandra X-ray Observatory went into into safe mode on October 10 for reasons that are either not yet understood or have not yet been revealed.

Chandra, Spitzer, and Hubble are the three remaining of the original four great observatories proposed in the late 1980s, with the Compton Gamma-Ray Observatory the fourth. Compton was de-orbited in 2000. Spitzer’s infrared observational capabilities became limited when its cryogenic cooling gas became exhaused in 2009.

Hubble and now Chandra are both in safe mode, leaving astronomy badly crippled.

This situation is actually the fault of the astronomical community, which in the early 2000s put all its money behind the James Webb Space Telescope, leaving little for the construction of replacement space telescopes for either Hubble or Chandra. In addition, the astronomical community has continued to put is money behind similar big, expensive, and giant projects like Webb, pushing for WFIRST with its 2011 decadal survey. Like Webb, WFIRST will cost billions and take almost a decade to build and launch, assuming there are no delays.

Meanwhile, the workhorses in orbit are failing one by one.

Chandra looks back at the Crab Nebula

Link here. It is almost twenty years since the Chandra X-Ray Observatory was launched, and in celebration the science team have released another X-ray image of the Crab Nebula, taken in 2017 in league with an optical image from the Hubble Space Telescope and an infrared image from the Spitzer Space Telescope. They have also provided links to all similar past images, going back to 1999.

Some of the images are actually videos, in 2002 and 2011, showing the Crab’s dynamic nature. You can actually see flares and waves of radiation rippling out from its center.