In a paper (paywalled) published in the journal Icarus, a team of scientists led by Carey Lisse and Ralph McNutt of the Johns Hopkins University Applied Physics Laboratory (that designed, built, and operates the New Horizons spacecraft) have made, using the Chandra X-Ray Telescope, the puzzling detection of X-ray emissions from Pluto. Being a cold, icy world with no magnetic field, Pluto has no obvious mechanism for producing X-rays, but it is known that the interaction of gases surrounding such bodies and the solar wind can produce X-rays, though the intensity of the emissions is still higher than would be expected given the measurements of the dwarf planet's tenuous atmosphere and its great distance from the sun. From the JHUAPL press release:
While NASA's New Horizons spacecraft was speeding toward and beyond Pluto, Chandra was aimed several times on the dwarf planet and its moons, gathering data on Pluto that the missions could compare after the flyby. Each time Chandra pointed at Pluto — four times in all, from February 2014 through August 2015 — it detected low-energy X-rays from the small planet.
[...] "We've just detected, for the first time, X-rays coming from an object in our Kuiper Belt, and learned that Pluto is interacting with the solar wind in an unexpected and energetic fashion," said Carey Lisse, an astrophysicist at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland, who led the Chandra observation team with APL colleague and New Horizons Co-Investigator Ralph McNutt. "We can expect other large Kuiper Belt objects to be doing the same."
[...] The immediate mystery is that Chandra's readings on the brightness of the X-rays are much higher than expected from the solar wind interacting with Pluto's atmosphere.
[...] Lisse and his colleagues [...] suggest several possibilities for the enhanced X-ray emission from Pluto. These include a much wider and longer tail of gases trailing Pluto than New Horizons detected using its SWAP instrument. Other possibilities are that interplanetary magnetic fields are focusing more particles than expected from the solar wind into the region around Pluto, or the low density of the solar wind in the outer solar system at the distance of Pluto could allow for the formation of a doughnut, or torus, of neutral gas centered around Pluto's orbit.
Other coverage from Starts With A Bang and Gizmodo.
Related Stories
After briefly going offline, NASA's Chandra X-ray space telescope is back in action
After briefly going into safe mode last week, NASA's Chandra X-ray Observatory — which observes galaxies and nebulas from Earth's orbit — should be getting back to normal operations soon. The cause of the disruption was a small glitch in one of the spacecraft's instruments used for steering and pointing. But the space agency has since fixed the problem, and the telescope will be back to observing the Universe by the end of the week.
[...] The glitch resulted in the gyro measuring three seconds of "bad data," which led Chandra's onboard computer to come up with the wrong value for the vehicle's momentum, according to NASA. This apparently prompted the safe mode. Now, NASA has decided to use one of Chandra's other gyros in its place and put the glitchy one on reserve.
Also at Space.com.
Previously: NASA's Chandra X-Ray Observatory Enters Safe Mode; Investigation Underway
Related: Puzzling X-Ray Emissions From Pluto
A New Stellar X-Ray 'Reality' Show Debuts
Galaxy Collision Creates Ring of Black Holes and Neutron Stars
(Score: -1, Redundant) by Anonymous Coward on Sunday September 18 2016, @11:10PM
That's no dwarf planet!
Age of referenced quote: 39 years.
Automatic mod-up to +10 Funny.
(Score: 0) by Anonymous Coward on Monday September 19 2016, @12:28AM
Right, because space stations routinely emit X-rays.
(Score: 0) by Anonymous Coward on Monday September 19 2016, @02:40AM
Star Wars isn't Designated-Funny anymore?! How could this happen! The Dark Side has won!
(Score: 0) by Anonymous Coward on Monday September 19 2016, @02:59AM
Heavy breathing.
(Score: 0) by Anonymous Coward on Monday September 19 2016, @03:22AM
I hate you! and I hate the harvest! I'm running away to join the empire! [cad-comic.com]
(Score: 4, Funny) by Kell on Monday September 19 2016, @12:32AM
No doubt it's a status report from Fwiffo.
Scientists ask questions. Engineers solve problems.
(Score: 2) by BK on Monday September 19 2016, @12:55AM
Greetings big and scary space observatory!
...but you HAVE heard of me.
(Score: 0) by Anonymous Coward on Monday September 19 2016, @02:32AM
I won't believe it's Spathi unless a slaveshield snaps on every time a probe flies by.
(Score: 2) by AnonymousCowardNoMore on Monday September 19 2016, @07:19PM
Winky's Happy Night!
(Score: 5, Funny) by Bogsnoticus on Monday September 19 2016, @01:45AM
With the increase in technology allowing humans to explore more and more areas, old St Nick had to abandon his fortress of solitude in the frozen north, and find a place where we won't easily stumble across his domicile.
This explains the xrays being produced by Pluto, as the elves are now ramping up production, and are busy wrapping presents [technologyreview.com].
Genius by birth. Evil by choice.
(Score: 2) by Mykl on Monday September 19 2016, @05:49AM
That's a possibility, though I had assumed it was the Fungi from Yuggoth [wikipedia.org] transmitting signals back to their cultists here on Earth
(Score: 2) by turgid on Monday September 19 2016, @08:36AM
There was me thinking it was David Icke developing his new death ray to liberate Earth from the Jewish Nazi Green Lizard Men and HRH Duke of Edinburgh.
I refuse to engage in a battle of wits with an unarmed opponent [wikipedia.org].
(Score: 2, Informative) by Anonymous Coward on Monday September 19 2016, @08:27AM
It is trying to kill those who demoted it.
(Score: 2) by turgid on Monday September 19 2016, @08:39AM
In other news, Mike Brown was seen leaving Tescos with a roll of Bacofoil under his arm.
I refuse to engage in a battle of wits with an unarmed opponent [wikipedia.org].
(Score: 3, Interesting) by VLM on Monday September 19 2016, @11:48AM
The 2001 book had the monolith on the moon discovered by noticing a large scale magnetic anomaly and I think the explanation / excuse was a large charged up superconductive ring
Anyway if you were a space alien and wanted to F with the locals by leaving behind weird trash, there do exist isotopes that squirt out xrays as they decay, however I'm having trouble finding a list and all I remember from memory is Fe55 would work great other than the half life being a couple years. Its surprisingly not straightforward to google for "xray isotopes" or whatever. Or its easy to find lists of EC decay isotopes and Mn53 has a tasty long half life but whats the decay spectrum, is it a yummy level xray?
(Score: 2) by butthurt on Monday September 19 2016, @03:54PM
> [...] I'm having trouble finding a list [...]
This page (Javascript may be required) lets one search a database:
http://nucleardata.nuclear.lu.se/toi/radSearch.asp [nuclear.lu.se]
for example, these decays have energies of 3 to 5 keV:
http://nucleardata.nuclear.lu.se/toi/Gamma.asp?sql=&sortBy=AZ&Min=3&Max=5 [nuclear.lu.se]