The companion rec roundup to episode 29, all about Mycroft. A little late? Blame Caroline, but is it ever a bad time for fic recs? 

Previously, we had asked you for Mycroft-worthy recs for our episode 29, The Smart One. We had a lot of variation in terms of ships and content, so we have more than one post for you. A separate post will be made available for just Mycroft/Sherlock (AKA Holmescest) ones.

@marsdaydream recced

alexxphoenix42 recced

  • Not Nice, by mildredandbobbin, rated E, 14k [Mystrade]

drinkingcocoa-tpp recced

daasgrrl recced

abbykate recced

stellamira1936 self-recced her WIP Mycroft-centric fic

@avawatson recced

rina996 self-recced a few Mystrade fics with fem!Greg

@soyeahso recced

  • He Ain’t Heavy, by dietplainlite, rated G, currently 900 (open ended drabble WIP) [Holmes brothers]
  • The Original Conjuring Cat, by dietplainlite, rated G, 1k [Holmes brothers]
  • Camping, by dietplainlite, rated G, 200 [Holmes brothers]
  • Le Luge, by cutebypsycho, rated G, 13k [Sally/Mycroft]

dingoesatemy recced

Find your true nickname:
  • ///////////////// BDAY MONTH:
  • January:curly
  • Febuary:leafy
  • March:pinkish
  • April:sparkly
  • May:royal
  • June:blue
  • July:slimy
  • August:chippy
  • September:yummy
  • October:sweet
  • November:girly
  • December:fabulous
  • ///////////////// BDAY DATE:
  • 1:elephant
  • 2:chipmunk
  • 3:pencil
  • 4:Pablo Picasso
  • 5:popcorn
  • 6:chocolate
  • 7:bubbles
  • 8:croc
  • 9:harley quinn
  • 10:kitty
  • 11:rubberband
  • 12:lemon
  • 13:shirt
  • 14:hottie
  • 15:chicken nugget
  • 16:rainbow
  • 17:bumble bee
  • 18:princess crown
  • 19:turtle
  • 20:dog
  • 21:cotton candy face
  • 22:maya hart
  • 23:lucaya queen
  • 24:riarkle queen
  • 25:chapstick
  • 26:baby lips
  • 27:pewdiepie
  • 28:nail polish
  • 29:sour patch kids
  • 30:yo mama
  • 31:classy mama on fleek

In episode 29, we’re looking at none other than the Smart One. That’s Mycroft Holmes, yes, but also Mark Gatiss! So if you’ve got recs for us, don’t be shy. Rec us fics, art, fanworks, and whatever else strikes your Mycroft/Gatissian fancy. Ships and ratings are open. Have a mystrade fic that didn’t make it into the mystrade episode we did in May? Dying to rec that johncroft fic you found this summer? Gotten into holmescest and don’t know what to do with all your recs? Got a Sherlock/League of Gentlemen fusion fic? Send them our way. Holmescest recs will feature in their own roundup, just FYI.

Send us your recs by email to or by submission to our tumblr, and remember to include links where possible. We’ll be collecting until Tuesday, October 28! Masterposts to come along with our episode, which drops on November 1.

Spoilercast 29: BRO LOC, The Other Bruh

Consulting Fans: @avawatson@dixiebell​, @cupidford, @unknownsister

In this episode: In which we round up week 1’s of series 4 #setlock spoilers.

Listen by streaming on our website or downloading. Subscribe on iTunes for the latest episodes! (Please note that Spoilercast is its own feed now, separate from @threepatchpodcast‘s feed!)

Hubble Finds Misbehaving Spiral
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NASA - Hubble Space Telescope patch.

Jan. 29, 2016

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Despite its unassuming appearance, the edge-on spiral galaxy captured in the left half of this NASA/ESA Hubble Space Telescope image is actually quite remarkable.

Located about one billion light-years away in the constellation of Eridanus, this striking galaxy — known as LO95 0313-192 — has a spiral shape similar to that of the Milky Way. It has a large central bulge, and arms speckled with brightly glowing gas mottled by thick lanes of dark dust. Its companion, sitting in the right of the frame, is known rather unpoetically as [LOY2001] J031549.8-190623.

Jets, outbursts of superheated gas moving at close to the speed of light, have long been associated with the cores of giant elliptical galaxies, and galaxies in the process of merging. However, in an unexpected discovery, astronomers found LO95 0313-192, even though it is a spiral galaxy, to have intense radio jets spewing out from its center. The galaxy appears to have two more regions that are also strongly emitting in the radio part of the spectrum, making it even rarer still.

The discovery of these giant jets in 2003 — not visible in this image, but indicated in this earlier Hubble composite — has been followed by the unearthing of a further three spiral galaxies containing radio-emitting jets in recent years. This growing class of unusual spirals continues to raise significant questions about how jets are produced within galaxies, and how they are thrown out into the cosmos.

For images and more information about Hubble, visit:

Text credits: ESA (European Space Agency)/Rob Garner/Image credits: ESA/Hubble & NASA; acknowledgement, Judy Schmidt.

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Grateful Dead
June 19, 1980
West High Auditorium
Anchorage, AK

Download: FLAC/MP3

Recording Info:
SBD -> Cassette Master

Transfer Info:
Cassette Master -> Sonic Solutions -> SBM2 -> CD

Mastering Info:
CD -> Samplitude Professional v8.01 -> FLAC
(2 Discs Audio / 2 Discs FLAC)

Cassette Masters supplied by Richard Hale
Transferred By David Gans
Patch Source Recorded By Mark Severson
Additional Mastering By Charlie Miller
November 29, 2006

Patch Info:
(FOB) Nak 700 -> Cassette Master -> Sound Forge 4.0 -> CD:
Alabama Getaway (0:00 – 0:16)
They Love Each Other (4:11 – 4:18)
Althea (6:20 – 7:13)
China Cat Sunflower (0:00 – 0:11)
Drums (5:20 – 5:37)

— Encore on end of Set 1 to fit show onto 2 discs
— Lost Sailor tease before Looks Like Rain

Set 1:
d1t01 – Alabama Getaway ->
d1t02 – The Promised Land
d1t03 – They Love Each Other ->
d1t04 – El Paso
d1t05 – Tennessee Jed
d1t06 – Cassidy
d1t07 – Althea ->
d1t08 – Looks Like Rain
d1t09 – Far From Me
d1t10 – The Music Never Stopped

Set 2:
d2t01 – China Cat Sunflower ->
d2t02 – I Know You Rider ->
d2t03 – C C Rider
d2t04 – Peggy-O
d2t05 – Lost Sailor ->
d2t06 – Saint Of Circumstance ->
d2t07 – Drums ->
d2t08 – Space ->
d2t09 – Wharf Rat ->
d2t10 – I Need A Miracle ->
d2t11 – Bertha ->
d2t12 – Good Lovin’

d1t11 – U.S. Blues*
*In order to fit the show on two disks the encore was originally placed at the end of disk 1.  I’ve left this for the FLACs but I went ahead and changed it on the MP3s so that the songs are in the right order.  – Mat

Hubble Peers into the Most Crowded Place in the Milky Way
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ESA - Hubble Space Telescope patch.

May 29, 2015

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This NASA/ESA Hubble Space Telescope image presents the Arches Cluster, the densest known star cluster in the Milky Way. It is located about 25,000 light-years from Earth in the constellation of Sagittarius (The Archer), close to the heart of our galaxy, the Milky Way. It is, like its neighbor the Quintuplet Cluster, a fairly young astronomical object at between two and four million years old.

The Arches cluster is so dense that in a region with a radius equal to the distance between the sun and its nearest star there would be over 100,000 stars! At least 150 stars within the cluster are among the brightest ever discovered in the Milky Way. These stars are so bright and massive that they will burn their fuel within a short time (on a cosmological scale that means just a few million years). Then they will die in spectacular supernova explosions. Due to the short lifetime of the stars in the cluster the gas between the stars contains an unusually high amount of heavier elements, which were produced by earlier generations of stars.

Hubble over sunrise
Despite its brightness the Arches Cluster cannot be seen with the naked eye. The visible light from the cluster is completely obscured by gigantic clouds of dust in this region. To make the cluster visible astronomers have to use detectors which can collect light from the X-ray, infrared, and radio bands, as these wavelengths can pass through the dust clouds. This observation shows the Arches Cluster in the infrared and demonstrates the leap in Hubble’s performance since its 1999 image of same object.

For more images and information about Hubble Space Telescope, visit: and

Image, Video, Credits: NASA/ESA, Text credit: European Space Agency (ESA).

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Cassini Watches Mysterious Feature Evolve in Titan Sea
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NASA / ESA - Cassini-Huygens Mission to Saturn & Titan patch.

September 29, 2014

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Image above: These three images, created from Cassini Synthetic Aperture Radar (SAR) data, show the appearance and evolution of a mysterious feature in Ligeia Mare, one of the largest hydrocarbon seas on Saturn’s moon Titan. Image Credit: NASA/JPL-Caltech/ASI/Cornell.

NASA’s Cassini spacecraft is monitoring the evolution of a mysterious feature in a large hydrocarbon sea on Saturn’s moon Titan. The feature covers an area of about 100 square miles (260 square kilometers) in Ligeia Mare, one of the largest seas on Titan. It has now been observed twice by Cassini’s radar experiment, but its appearance changed between the two apparitions.

Images of the feature taken during the Cassini flybys are available at:

The mysterious feature, which appears bright in radar images against the dark background of the liquid sea, was first spotted during Cassini’s July 2013 Titan flyby. Previous observations showed no sign of bright features in that part of Ligeia Mare. Scientists were perplexed to find the feature had vanished when they looked again, over several months, with low-resolution radar and Cassini’s infrared imager. This led some team members to suggest it might have been a transient feature. But during Cassini’s flyby on August 21, 2014, the feature was again visible, and its appearance had changed during the 11 months since it was last seen.

Scientists on the radar team are confident that the feature is not an artifact, or flaw, in their data, which would have been one of the simplest explanations. They also do not see evidence that its appearance results from evaporation in the sea, as the overall shoreline of Ligeia Mare has not changed noticeably.

The team has suggested the feature could be surface waves, rising bubbles, floating solids, solids suspended just below the surface, or perhaps something more exotic.

The researchers suspect that the appearance of this feature could be related to changing seasons on Titan, as summer draws near in the moon’s northern hemisphere. Monitoring such changes is a major goal for Cassini’s current extended mission.

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Cassini-Huygens spacecraft. Image Credits: NASA/JPL-Caltech
“Science loves a mystery, and with this enigmatic feature, we have a thrilling example of ongoing change on Titan,“ said Stephen Wall, the deputy team lead of Cassini’s radar team, based at NASA’s Jet Propulsion Laboratory in Pasadena, California. "We’re hopeful that we’ll be able to continue watching the changes unfold and gain insights about what’s going on in that alien sea.”

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and ASI, the Italian Space Agency. JPL, a division of the California Institute of Technology in Pasadena, manages the mission for NASA’s Science Mission Directorate, Washington. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries.

For more information about Cassini and its mission, visit: and and

Images (mentioned), Text, Credits: NASA / JPL / Preston Dyches.

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Dawn Spirals Closer to Ceres, Returns a New View
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NASA - Dawn Mission patch.

May 29, 2015

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Image above: A new view of Ceres’ surface shows finer details coming into view as NASA’s Dawn spacecraft spirals down to increasingly lower orbits. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.

A new view of Ceres, taken by NASA’s Dawn spacecraft on May 23, shows finer detail is becoming visible on the dwarf planet. The spacecraft snapped the image at a distance of 3,200 miles (5,100 kilometers) with a resolution of 1,600 feet (480 meters) per pixel. The image is part of a sequence taken for navigational purposes.

Image is available at:

After transmitting these images to Earth on May 23, Dawn resumed ion-thrusting toward its second mapping orbit. On June 3, Dawn will enter this orbit and spend the rest of the month observing Ceres from 2,700 miles (4,400 kilometers) above the surface. Each orbit during this time will be about three days, allowing the spacecraft to conduct an intensive study of Ceres.

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Image above: What’s the spot on World Ceres? Can you guess what’s creating those unusual bright spots on Ceres? On March 6, NASA’s Dawn spacecraft began orbiting Ceres, the largest body in the main asteroid belt between Mars and Jupiter. Even before the spacecraft arrived at the dwarf planet, images revealed mysterious bright spots that captivated scientists and observers alike. Until Dawn gets a closer look over the next few months, it’s anyone’s guess what those spots could be. So, go ahead! Cast your vote here: (Image Credit: NASA).

Dawn is the first mission to visit a dwarf planet, and the first to orbit two distinct solar system targets. It studied the protoplanet Vesta for 14 months in 2011 and 2012, and arrived at Ceres on March 6, 2015.

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Animation above: Rotating Ceres and is mysterious two spots. Animation Credits: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.
Dawn’s mission is managed by JPL for NASA’s Science Mission Directorate in Washington. Dawn is a project of the directorate’s Discovery Program, managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama. UCLA is responsible for overall Dawn mission science. Orbital ATK Inc., in Dulles, Virginia, designed and built the spacecraft. The German Aerospace Center, Max Planck Institute for Solar System Research, Italian Space Agency and Italian National Astrophysical Institute are international partners on the mission team. For a complete list of mission participants, visit:

More information about Dawn is available at the following sites: and

Images (mentioned), Text, Credits: NASA/JPL/Elizabeth Landau/Preston Dyches.

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Saturn - Spirals in the D Ring
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NASA & ESA - Cassini-Huygens Mission to Saturn & Titan patch.

June 29, 2015

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 Spirals in the D Ring
Image above: Although the D ring of Saturn is so thin that it’s barely noticeable compared to the rest of the ring system, it still displays structures seen in other Saturnian rings. Here the spiral structures in the D ring are on display.

The D ring spirals, discovered in Cassini images, are believed to be due to a warp in the ring created in the early 1980s. The precise mechanism remains the subject of scientific debate.  Over the course of the Cassini mission, scientists have been able to observe the spiral winding ever more tightly as it evolves. For more about the spiral.

(The bright specks and faint vertical streaks are merely image artifacts.  The processes typically employed to remove these artifacts would also have degraded the exquisite details of the D ring which are visible here.)

This view looks toward the sunlit side of the rings from about 22 degrees above the ringplane. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on July 6, 2013.

The view was acquired at a distance of approximately 350,000 miles (563,000 kilometers) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 131  degrees. Image scale is 2.1 miles (3.4 kilometers) per pixel.

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Tilting Saturn’s Rings
Animation above: This animated graphic shows in a series of three images how Saturn’s rings, after they became tilted relative to Saturn’s equatorial plane, would have transformed into a corrugated ring.

Images taken after Saturn’s August 2009 equinox from NASA’s Cassini spacecraft revealed alternating light and dark bands extending from Saturn’s D ring, completely across the C ring, and right up to the inner B ring edge. These brightness variations are almost certainly caused by the changing slopes in the rippled ring plane, much like the corrugations of a tin roof.

This series of images shows how such a vertical corrugation can be produced from an initially inclined ring by the natural tendency for inclined orbits to wobble systematically and slowly at different rates, depending on their distance from Saturn. The top image shows a simple inclined ring (the central planet is omitted for clarity), while the lower two images show the same ring at two later times, where the ring particles’ wobbling orbits have sheared this inclined sheet into an increasingly tightly-wound spiral corrugation.

Cassini images show the corrugation extends for 19,000 kilometers (12,000 miles). Based on detailed studies of this structure, scientists conclude that a broad swath of the rings became suddenly tilted in the early 1980s, likely because cometary debris crashed into the rings. The corrugation’s radial extent implies that the impacting material was a dispersed cloud of debris instead of a single object. The corrugation’s amplitude of 2 to 20 meters (7 to 60 feet) indicates that the debris’ total mass was around 1 trillion kilograms (or one billion metric tons).

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A Twisted Tale
Original Caption Released with Image:

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Figure 1
Images above: Saturn’s D ring–the innermost of the planet’s rings – sports an intriguing structure that appears to be a wavy, or “vertically corrugated,” spiral. This continuously changing ring structure provides circumstantial evidence for a possible recent collision event in the rings.

Support for this idea comes from the appearance of a structure in the outer D-ring that looks, upon close examination, like a series of bright ringlets with a regularly spaced interval of about 30 kilometers (19 miles). When viewed along a line of sight nearly in the ringplane, a pattern of brightness reversals is observed: a part of the ring that appears bright on the far side of the rings appears dark on the near side of the rings, and vice versa (see Image bellow).

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D Ring Sight Lines
Image above: A vertical corrugation in Saturn’s almost transparent D ring can give rise to brightness variations.

In this graphic representation, the diagonal lines (or arrows) correspond to lines of sight through the corrugated ring. The grayscale plot along the bottom shows the ring’s total optical depth (a measure of opacity) and brightness as seen by the observer.

This phenomenon would occur if the region contains a sheet of fine material that is vertically corrugated, like a tin roof. In this case, variations in brightness would correspond to changing slopes in the rippled ring material (see figure 1).

An observation made with NASA’s Hubble Space Telescope in 1995 also saw a periodic structure in the outer D ring, but its wavelength was then 60 kilometers (37 miles). There were insufficient observations to discern the spiral nature of the feature. Thus, it appears the wavelength of the wavy structure has been decreasing: that is, this feature has been winding up like a spring over time.

The rate at which the pattern appears to be winding up is quite close to the rate scientists would expect for a vertically corrugated spiraling sheet of material at this location in the rings that is responding to gravitational forcing from Saturn.

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Cassini passing over the Saturn rings
As Cassini imaging scientists extrapolated the spiraling trend backward in time, they found that it completely unwound in 1984, leaving only an inclined, or tilted, sheet of material. The researchers speculate such an inclined sheet may have been produced around that time by the impact of a comet or meteoroid into the D ring which kicked out a cloud of fine particles that ultimately inherited some of the tilt of the impactor’s trajectory as it slammed into the rings. Another possibility is that the impactor struck an already inclined moonlet, shattered it to bits and the debris remained in an inclined orbit.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA’s Science Mission Directorate, Washington, D.C.

For more information about the Cassini-Huygens mission visit or The Cassini imaging team homepage is at and

Images, Text, Credits: NASA/JPL-Caltech/Space Science Institute/Cornell.

Best regards,
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NASA's NuSTAR Captures Possible 'Screams' from Zombie Stars
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NASA - Nuclear Spectroscopic Telescope Array (NuSTAR) patch.

April 29, 2015

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Image above: NASA’s Nuclear Spectroscopic Telescope Array, or NuSTAR, has captured a new high-energy X-ray view of the bustling center of our Milky Way galaxy. Image Credits: NASA/JPL-Caltech.

Peering into the heart of the Milky Way galaxy, NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR) has spotted a mysterious glow of high-energy X-rays that, according to scientists, could be the “howls” of dead stars as they feed on stellar companions.

“We can see a completely new component of the center of our galaxy with NuSTAR’s images,” said Kerstin Perez of Columbia University in New York, lead author of a new report on the findings in the journal Nature. “We can’t definitively explain the X-ray signal yet – it’s a mystery. More work needs to be done.”

The center of our Milky Way galaxy is bustling with young and old stars, smaller black holes and other varieties of stellar corpses – all swarming around a supermassive black hole called Sagittarius A*.

NuSTAR, launched into space in 2012, is the first telescope capable of capturing crisp images of this frenzied region in high-energy X-rays. The new images show a region around the supermassive black hole about 40 light-years across. Astronomers were surprised by the pictures, which reveal an unexpected haze of high-energy X-rays dominating the usual stellar activity.

“Almost anything that can emit X-rays is in the galactic center,” said Perez. “The area is crowded with low-energy X-ray sources, but their emission is very faint when you examine it at the energies that NuSTAR observes, so the new signal stands out.”

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Image above: NASA’s Nuclear Spectroscopic Telescope Array, or NuSTAR, has captured a new high-energy X-ray view (magenta) of the bustling center of our Milky Way galaxy. The smaller circle shows the center of our galaxy where the NuSTAR image was taken. Image Credits: NASA/JPL-Caltech.

Astronomers have four potential theories to explain the baffling X-ray glow, three of which involve different classes of stellar corpses. When stars die, they don’t always go quietly into the night. Unlike stars like our sun, collapsed dead stars that belong to stellar pairs, or binaries, can siphon matter from their companions. This zombie-like “feeding” process differs depending on the nature of the normal star, but the result may be an eruption of X-rays.

According to one theory, a type of stellar zombie called a pulsar could be at work. Pulsars are the collapsed remains of stars that exploded in supernova blasts. They can spin extremely fast and send out intense beams of radiation. As the pulsars spin, the beams sweep across the sky, sometimes intercepting the Earth, like lighthouse beacons.

“We may be witnessing the beacons of a hitherto hidden population of pulsars in the galactic center,” said co-author Fiona Harrison of the California Institute of Technology (Caltech) in Pasadena, and principal investigator of NuSTAR. “This would mean there is something special about the environment in the very center of our galaxy.”

Other possible culprits include heavy-set stellar corpses called white dwarfs, which are the collapsed, burned-out remains of stars not massive enough to explode in supernovae. Our sun is such a star, and is destined to become a white dwarf in about five billion years. Because these white dwarfs are much denser than they were in their youth, they have stronger gravity and can produce higher-energy X-rays than normal. Another theory points to small black holes that slowly feed off their companion stars, radiating X-rays as material plummets down into their bottomless pits.

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NASA’s Nuclear Spectroscopic Telescope Array, or NuSTAR. Image Credits: NASA/JPL-Caltech
Alternatively, the source of the high-energy X-rays might not be stellar corpses at all, astronomers say, but rather a diffuse haze of charged particles, called cosmic rays. The cosmic rays might originate from the supermassive black hole at the center of the galaxy as it devours material. When the cosmic rays interact with surrounding, dense gas, they emit X-rays.

However, none of these theories match what is known from previous research, leaving the astronomers largely stumped.

“This new result just reminds us that the galactic center is a bizarre place,” said co-author Chuck Hailey of Columbia University. “In the same way people behave differently walking on the street instead of jammed on a crowded rush hour subway, stellar objects exhibit weird behavior when crammed in close quarters near the supermassive black hole.”

The team says more observations are planned. Until then, theorists will be busy exploring the above scenarios or coming up with new models to explain what could be giving off the puzzling high-energy X-ray glow.

“Every time that we build small telescopes like NuSTAR, which improve our view of the cosmos in a particular wavelength band, we can expect surprises like this,” said Paul Hertz, the astrophysics division director at NASA Headquarters in Washington.

NuSTAR is a Small Explorer mission led by Caltech and managed by NASA’s Jet Propulsion Laboratory in Pasadena, California, for NASA’s Science Mission Directorate in Washington.

More information is online at:

Images (mentioned), Text, Credits: NASA/Felicia Chou/JPL/Whitney Clavin/Karen Northon.

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A Solar Wind Workhorse Marks 20 Years of Science Discoveries
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NASA - Wind Mission patch.

December 29, 2014

The end of 2014 marks two decades of data from a NASA mission called Wind. Wind – along with 17 other missions – is part of what’s called the Heliophysics Systems Observatory, a fleet of spacecraft dedicated to understanding how the sun and its giant explosions affect Earth, the planets and beyond.

Wind launched on Nov. 1, 1994, with the goal of characterizing the constant stream of particles from the sun called the solar wind. With particle observations once every 3 seconds, and 11 magnetic measurements every second, Wind measurements were – and still are – the highest cadence solar wind observations for any near-Earth spacecraft.

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Image above: The Wind spacecraft has spent much of its 20 years in space out in front of the magnetic fields – the magnetosphere – that surrounds Earth, observing the constant stream of particles flowing by from the solar wind. Image Credit: NASA.

During its more than 20 years in space, Wind has taken up position at various spots around our planet to help determine how near-Earth space interacts with incoming energy and particles from the sun. Assessing the complex variations of the charged particles making up the solar wind cannot be done from a single point in space. That would be like trying to understand the entire Earth’s weather system from a single collection station in Washington, D.C. So, Wind was part of a game changing idea: launch several missions to work in tandem to understand how the dynamic magnetosphere surrounding Earth reacts to the sun. Sitting at a point between Earth and the sun, Wind was the vanguard, observing the solar wind.

“We had a fairly simple original objective,” said Adam Szabo, the project scientist for Wind at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “The number one question was to find out how the solar wind was driving changes in the magnetosphere.”

The original flotilla, named the Global Geospace Science (GGS) campaign, was composed of the Polar spacecraft observing Earth’s magnetosphere in high latitudes, Equator-S making equatorial magnetospheric measurements, and the Japanese Geotail patrolling the elongated magnetotail  – the long ribbon of magnetosphere that trails behind Earth, away from the sun. The original GGS program was rapidly extended with additional missions to form the International Solar Terrestrial Program, or ISTP.

With its mandate to watch the frontlines, Wind was sent into orbit around what’s called a Lagrangian point, a point that experiences balanced gravity from both the sun and Earth. Wind took up residence in an elliptical orbit around the first Langrangian point (L1), lying between Earth and the sun, some 932,000 miles away from Earth. While several satellites have since been in a similar orbit, Wind was only the second spacecraft ever to orbit L1.

In 1997, another solar wind monitor joined the L1 neighborhood. The Advanced Composition Explorer, or ACE, was designed both to measure properties of the incoming solar wind, and to give scientists advanced notice of larger, more intense eruptions from the sun, such as coronal mass ejections, or CMEs. At their worst, CMEs can compress the magnetosphere so severely that satellites suddenly find themselves outside that protective bubble, exposed to harsh solar radiation. The compression can also set off vibrations in the magnetosphere that can induce electrical surges in power grids on Earth.

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Graphic of Wind spacecraft. Image Credit: NASA
NASA decided to take advantage of having two spacecraft monitoring the solar wind by moving Wind to the second Lagrange point (L2), a point on the other side of Earth from the sun. L2 is some 1.1 million miles down the magnetotail, four times the distance to the moon. From this new location, Wind was able to provide measurements from deeper in the magnetotail than any other missions have done.

Working together, ACE and Wind unraveled even more mysteries about the solar wind, helping answer questions such as, did the observations on one side correlate to what was happening on the other? Did any particular occurrence stay coherent over long distances or did they change as they moved?

During this time frame, the ISTP missions helped scientists understand more about the size of events in the magnetosphere. At a distance of under 90,000 miles, what one satellite observed could be correlated to measurements from the other. That means that knowing what one satellite saw could perhaps be used to predict what might be seen elsewhere in the magnetosphere, as long as it was less than 90,000 miles away.  At greater distances, however, any given blast of energy or particles moving through the magnetosphere simply changed too much to be predictable.

From 2000-2003, Wind moved through a variety of positions, including off to the side of the magnetosphere, 1.5 million miles away from Earth, and a return trip to the magnetotail. In 2004, Wind was moved back to the L1 point permanently.

“In its position at L1, Wind has witnessed a handful of first ever sightings of different kinds of electromagnetic waves traveling by in the solar wind,” said Lynn Wilson, deputy project scientist for Wind at Goddard. “In space where a particle could travel 100 million miles before hitting another one, these waves simply can’t be working the same way sound or water waves do, pushing material along. It has opened up whole areas of research trying to understand these unexpected properties.”

Wind continues to work with other spacecraft – and is even looking to the future. In 2018, NASA will launch a new mission called Solar Probe Plus that will go to within 3.8 million miles of the sun to explore what happens within the solar wind near the sun. One big mystery is the question of what keeps the solar wind heated. One would think that the solar wind would cool down as it expands and travels away from the sun, but it remains hotter than expected. Some intrinsic activity within the wind must continue to generate heat. It is known that magnetic reconnection – a process in which magnetic energy is converted into heat and acceleration of particles – is part of the process. In sync with this endeavor, Wind has searched for the signatures of magnetic reconnection closer to home.

“The question we had was whether magnetic reconnection could ever happen in the low density solar wind, where things are not as dynamic as in the sun’s atmosphere,” said Szabo. “Wind found signatures of reconnection, but they weren’t violent reactions like what happens closer to the sun. These were subtle, lower energy events, and the signature were thin streams of particles accelerating outward, which we call reconnection jets.”

These jets last for such short periods of time that the 3-second data collection on Wind is just barely fast enough to capture them – an example of how Wind’s high cadence measurements still shine 20 years after launch, and how its mission continues to offer important data for scientists.

Despite having a planned mission of five years, Wind was built with the hope of lasting much longer. Wind has enough fuel to keep it in orbit around L1 until 2074, and every effort has been made to reduce stress on its instruments in order to maintain their longevity. At 20 years, it is still going strong and helping scientists understand the forces that buffet near-Earth space.

Related Links:

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Images (mentioned), Text, Credits: NASA’s Goddard Space Flight Center/Karen C. Fox.

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