Despite the recent whinging about whether or not the maps on the Pioneer and Voyager space probes might have been a big mistake that might lead to Earth being invaded by hostile aliens, it turns out that the pulsar maps included on these probes are actually worthless for determining the location of our Solar System. Pulsars were first discovered in 1967 by Jocelyn Bell-Burnell, and at the time they were believed to be unique and stable landmarks suitable for that purpose. However, subsequent discoveries have shown that they are not actually as stable and reliable as they were first believed. Ethan Siegel at Starts With A Bang has an article on this:
[...] While fear-mongers foolishly claim that hostile aliens could follow the Voyager maps back to Earth, the maps themselves are actually among the most useless information aboard Voyager. According to Frank Drake, who worked on the Voyager message with Carl Sagan:
"We needed to put something on the Voyager that said where it came from, and how long it was traveling... There was a magic about pulsars ... no other things in the sky had such labels on them. Each one had its own distinct pulsing frequency, so it could be identified by anybody, including other creatures after a long period of time and far, far away."
Although these identifiers were thought to be unique and stable, we now know that long-term changes will render this map useless. If you tried to identify Earth by the presence of Pangaea, you'd be sorely disappointed. By sending the messages we did with Voyager, we actually delivered a much more challenging problem to any aliens "lucky" enough to come upon it. The idea to send pulsar positions and frequencies was a brilliant one, but by the time anyone receives it, they'll only encounter one of the most difficult-to-decipher riddles we could have possibly imposed.
In summary, it turns out that pulsars are far from being as unique, rare, and stable as they were believed to be in the 1970s when they came up with the idea. There are an estimated one billion neutron stars in the Milky Way, and almost all of these will look like pulsars somewhere in space because their spin and magnetic axes aren't perfectly aligned and so they will beam radio waves in some direction. The pulsar periods are also not as unique as they were at the time believed, so any extraterrestrial finding the Voyager plaque will have a hard time figuring out which fourteen pulsars out of a billion are described. Second, the properties of a pulsar can change in unpredictable fashion. Pulsars have since been observed to appear and disappear as the orientations of their spins relative to Earth change due to various factors, such as their motion in space and events internal to the pulsar itself such as starquakes and pulsar speedup. If one really wanted to tell aliens were we were it would have been better to give them a description of the Solar System, with the astronomical properties and description of our sun and the planets. It is, after all, how we identify exoplanet systems today.
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Was NASA hasty in including a pulsar map to Earth on the Pioneer plaques and Voyager Golden Records?
Forty years ago, we sent a map to Earth sailing deep into the cosmos. Copies of this map are etched into each of the twin Voyager spacecraft, which launched in the late 1970s and are now the farthest spacecraft from home. One of the probes has already slipped into interstellar space, and the other is skirting the fringes of our sun's immediate neighborhood. If it's ever intercepted and decoded by extraterrestrials, the map will not only reveal where to find our watery little world, but also when the space probe that delivered it to alien hands left home.
[...] "Back when Drake did the pulsar map, and Carl Sagan and the whole team did the Voyager record, there hadn't been very much debate over the pros and cons of contact with extraterrestrial intelligence," says York University's Kathryn Denning, an anthropologist who studies the ethics of sending messages to extraterrestrials. "Now, however, as you know, there is a major debate among scientists and a variety of stakeholders about the wisdom of doing anything other than listening."
[...] "In those days, all the people I dealt with were optimists, and they thought the ETs would be friendly," Drake says. "Nobody thought, even for a few seconds, about whether this might be a dangerous thing to do." So what are the chances of the map actually reaching extraterrestrial shores aboard the Voyagers? "Very small," Drake says. "The thing is going something like 10 kilometers per second, at which speed it takes—for the typical separation of stars—about half a million years to go from one star to another. And of course, it's not aimed at any star, it's just going where it's going."
Of course, aliens could just use gigantic space telescopes to find Earth and other watery planets instead of accidentally intercepting a tiny spacecraft. And humanity will either be super-advanced, post-apocalyptic, or just gone by the time aliens can find a map and head for Earth (even if they have faster-than-light travel, the spacecraft won't be relatively far away from Earth anytime soon).
Also at Boing Boing and The Sun (not that one).
NASA's Voyager mission was launched 40 years ago:
NASA's historic Voyager mission has now been exploring the heavens for four decades.
The Voyager 2 spacecraft launched on Aug. 20, 1977, a few weeks before its twin, Voyager 1. Together, the two probes conducted an unprecedented "Grand Tour" of the outer solar system, beaming home up-close looks at Jupiter, Saturn, Uranus, Neptune and many of the moons of these giant planets.
This work revealed a jaw-dropping diversity of worlds, fundamentally reshaping scientists' understanding of the solar system. And then the Voyagers kept on flying. In August 2012, Voyager 1 became the first spacecraft ever to reach interstellar space — and Voyager 2 is expected to arrive in this exotic realm soon as well.
The rest of the article is a Q&A with Voyager project scientist and former director of the NASA Jet Propulsion Laboratory Ed Stone.
Also at BBC and NBC. Image gallery at Ars Technica. A PBS special about the mission will air on August 23.
No missions have been sent to Uranus or Neptune since Voyager 2 visited them in 1986 and 1989.
Related: Pioneer and Voyager Maps to Earth: How Much of a Mistake?
Voyager's 'Cosmic Map' Of Earth's Location Is Hopelessly Wrong
NASA Team First to Demonstrate X-ray Navigation in Space
In a technology first, a team of NASA engineers has demonstrated fully autonomous X-ray navigation in space — a capability that could revolutionize NASA's ability in the future to pilot robotic spacecraft to the far reaches of the solar system and beyond.
The demonstration, which the team carried out with an experiment called Station Explorer for X-ray Timing and Navigation Technology, or SEXTANT, showed that millisecond pulsars could be used to accurately determine the location of an object moving at thousands of miles per hour in space — similar to how the Global Positioning System, widely known as GPS, provides positioning, navigation, and timing services to users on Earth with its constellation of 24 operating satellites.
[...] The SEXTANT technology demonstration, which NASA's Space Technology Mission Directorate had funded under its Game Changing Program, took advantage of the 52 X-ray telescopes and silicon-drift detectors that make up NASA's Neutron-star Interior Composition Explorer, or NICER. Since its successful deployment as an external attached payload on the International Space Station in June, it has trained its optics on some of the most unusual objects in the universe.
"We're doing very cool science and using the space station as a platform to execute that science, which in turn enables X-ray navigation," said Goddard's Keith Gendreau, the principal investigator for NICER, who presented the findings Thursday, Jan. 11, at the American Astronomical Society meeting in Washington. "The technology will help humanity navigate and explore the galaxy."
Neutron Star Interior Composition Explorer
Previously: NASA to Study Neutron Stars; Sends New Instrument to ISS; SpaceX Launch Sat @ 2107 UTC (1707 EDT)
Related: Voyager's 'Cosmic Map' Of Earth's Location Is Hopelessly Wrong
(Score: 5, Funny) by looorg on Friday August 18 2017, @11:41PM (6 children)
The alien overlords will not be impressed with our lack of pulsar knowledge. One wonders if this is what drives them into a killing frenzy.
(Score: 3, Funny) by takyon on Friday August 18 2017, @11:55PM
Wasn't this regularity [metawellness.com] of pulsars supposed to make space navigation a cinch for our space battleships?
We're literally lost in space!
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 3, Funny) by Anonymous Coward on Saturday August 19 2017, @12:35AM (3 children)
We're safe. The alien overlords are male and they are NOT going to stop and ask for directions.
(Score: 2) by looorg on Saturday August 19 2017, @12:49AM (2 children)
Not being male would/could explain why it's taking so long for them to get here, they are not even driving at the intergalactic speed-limit. Plus they are probably stopping at every store there is between there and here.
(Score: 5, Funny) by maxwell demon on Saturday August 19 2017, @04:51AM (1 child)
The danger is an alien couple. The female will ask for directions, and the male will drive at maximum speed and insist on her not visiting any shops. And on arrival, they will both be in very bad mood because of the inevitable arguments about visiting shops, his driving style, and so on. Destroying Earth will be a welcome opportunity for them to let off steam.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 2) by melikamp on Saturday August 19 2017, @05:33AM
(Score: 0) by Anonymous Coward on Saturday August 19 2017, @08:08AM
Inter-Galactic Planetary Pizza Delivery
Driver: Captain, it's a fake address.
Captain: What? Again?? This is the last straw!
Driver: I told you it looked fishy. Who orders a pizza via probe?
Captain: Oh, shut up. You're cleaning the bathrooms when you get back!
(Score: 2) by bob_super on Friday August 18 2017, @11:45PM (1 child)
The aliens at Intergalactic Biggiest Machines will solve the riddle in a few minutes by querying their starfield Big Data and find us. One of them will proudly go this his boss to show how the continuous storage of massive amounts of pulsar data wasn't as useless as it seemed.
The only question is whether they'll beat the SpaceBook guys to it, since they do have the Roswell selfies.
(Score: 3, Touché) by looorg on Saturday August 19 2017, @12:00AM
Multiple aliens probing for our affection(s), sweet!
(Score: 2) by Snotnose on Saturday August 19 2017, @12:05AM (1 child)
So when the aliens are told "turn left 100 ft" and they blindly turn into the equivalent of a railroad track, it's somehow *our* fault?
I blame dumass aliens for making such a stupid turn.
When the dust settled America realized it was saved by a porn star.
(Score: 0) by Anonymous Coward on Saturday August 19 2017, @03:19AM
Made me think of https://www.youtube.com/watch?v=DOW_kPzY_JY&t=27 [youtube.com] with the best part being the perfectly timed, "make a U-turn if possible."
(Score: 2, Offtopic) by Runaway1956 on Saturday August 19 2017, @12:35AM (14 children)
Keep in mind that each and every space faring race that originated on a planet is either the apex predator, or has defeated the apex predator on it's home planet.
For example - mankind.
Perhaps an intelligent race that developed in space could be different, but that's unlikely, IMHO.
Oh, wait, some of you silly people thought that predation was unique to earth life? ROFLMAO
(Score: 1) by Virindi on Saturday August 19 2017, @12:52AM (9 children)
This is a bit circular.
What allowed humans to build civilization is not that we were the biggest, baddest predator on the planet. In terms of raw brawn we rank somewhere in the middle.
The fact that we are NOT the biggest and baddest meant there was an evolutionary advantage to developing clever tricks and good ability to cooperate, which is the intelligence which led to civilization. It seems perfectly plausible that a physically weak species could develop intelligence and build a civilization given the right conditions. And, of course, once they had developed technology they would then be "apex" in the sense that their technology, like ours, would allow them to be safe from any predator on the planet.
(Score: 3, Insightful) by Arik on Saturday August 19 2017, @02:40AM (6 children)
In the middle of what?
A naked human is nowhere near parity with any other animal in the same weight class.
If laughter is the best medicine, who are the best doctors?
(Score: 0) by Anonymous Coward on Saturday August 19 2017, @03:07AM (4 children)
A naked human can survive and recover from injuries that would send most other wildlife into shock/stasis and certain death.
(Score: 2) by Arik on Saturday August 19 2017, @05:52AM (3 children)
Other answer was better. We're larger than most other animals. Definitely not all.
If laughter is the best medicine, who are the best doctors?
(Score: 2) by maxwell demon on Saturday August 19 2017, @07:09AM (2 children)
We are larger than most animals that are not yet extinct. There were plenty more large animals in the early times of humans.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 2) by Arik on Saturday August 19 2017, @04:40PM (1 child)
Well *plenty more* isn't exactly quantifiable but you need that wiggle room.
There were mammoths but they weren't too different from elephants we still have today. The bulk of species, then and now, were tiny thing - insects, rodents, small birds etc.
If laughter is the best medicine, who are the best doctors?
(Score: 2) by darkfeline on Tuesday August 22 2017, @03:32AM
Elephants are only still extant because we decided to protect them as a society. Let the ivory poachers alone and they'll disappear right quick.
Same for everything else. Whales, etc.
Join the SDF Public Access UNIX System today!
(Score: 0) by Anonymous Coward on Saturday August 19 2017, @04:10AM
In the middle, between, say, a gerbil in the throes of bloodlust, and any fair-sized canid or feline?
GP didn't say anything about weight class.
(Score: 0) by Anonymous Coward on Saturday August 19 2017, @08:17AM
Um, that's impossible considering evolution is just a theory, the Earth is only 6,000 years old and the Bible clearly states that we "have dominion over the fish of the sea and over the birds of the heavens and over the livestock and over all the earth and over every creeping thing that creeps on the earth." That pretty much makes us the apex of apexes. /s
(Score: 3, Interesting) by Runaway1956 on Saturday August 19 2017, @01:33PM
There is strength in the herd. Hominids are pack animals. Before we tamed fire, before we invented the wheel, before any technology, we learned how to protect the herd. When we had nothing more than some sticks and stones that we found laying about, we were putting the hurt on creatures much larger than ourselves, not to mention succulent little critters. Youtube is filled with videos of various apes and monkeys acting in concert. One of the more fascinating videos showed baboons domesticating dogs. Pretty cool, huh?
https://www.youtube.com/watch?v=U2lSZPTa3ho [youtube.com]
(Score: 3, Interesting) by Arik on Saturday August 19 2017, @02:20AM (3 children)
If laughter is the best medicine, who are the best doctors?
(Score: 0) by Anonymous Coward on Saturday August 19 2017, @02:29AM
Sasquatch
(Score: 3, Funny) by Anonymous Coward on Saturday August 19 2017, @08:19AM
Glaciers. They've been retreating ever since modern man showed up and they're still on the run.
(Score: 3, Insightful) by Runaway1956 on Saturday August 19 2017, @01:21PM
All of them, of course. Wolves and coyotes and all their brethren. Mountain lion, cougar, lion, and all of their kin. Bears, wolverines, badgers, and related critters. The deadliest snakes try to avoid man - there are only a couple in the world that can consume a smallish human, and they have no other use for mammals. We have NOT displaced those creatures that we consider "vermin". Rats, roaches, mice, houseflies (among other species of flies, like bot flies), mosquitos, spiders - size works in their favor as much as anything.
(Score: 0) by Anonymous Coward on Saturday August 19 2017, @12:39AM
So, L. Ron Hubbard's aliens won't be able to disassemble Earth after all?
(Score: 3, Insightful) by el_oscuro on Saturday August 19 2017, @01:53AM
The Vogons in the local planning office in Alpha Centurai already know about Earth. There is a construction project scheduled here but I think it has been delayed due to the bureaucracy.
SoylentNews is Bacon! [nueskes.com]
(Score: 1, Interesting) by Anonymous Coward on Saturday August 19 2017, @05:16AM
Supposedly there's a "a proton-superconductor phase of matter" [wikipedia.org] within the neutron star.
(Score: 0) by Anonymous Coward on Saturday August 19 2017, @06:42AM
They're irregular because pulsars are electric discharges. The same cosmic scale charge flow that creates spiral arms of galaxies also builds up at more insulative areas then zaps across the spark gap and generates the radio pulse we hear.
Marconi, eat your heart out.
(Score: 2) by zeigerpuppy on Saturday August 19 2017, @07:37AM (3 children)
I would have thought that an observation of the trajectory, speed and rough amount of ablation on the shield would be plenty to work out where it came from even without a map!
(Score: 3, Insightful) by theluggage on Saturday August 19 2017, @08:42AM
Or it could go like this:
"Ah, Science Officer Y'baH-Txk, any progress on tracing the origin of that alien probe we picked up? Have you decoded the plaque? Or calculated it's trajectory, perhaps?"
"No, Brood Captain Kzyg't$_14, but we think that maybe, just maybe, since it was only moving at a tiny fraction of lightspeed and hadn't yet crumbled to dust, we should start looking at the only fucking solar system within a light year or so of where we picked it up."
Science Officer Y'baH-Txk slithers away to write an angry internal memo about diversity policies that let Quarathoids become Brood Captains despite only having 3 brains and no p'tuk.
As long as hungry aliens don't find the probe and come calling for another 100,000 years or so, when they do arrive I'm sure that our future cockroach-descended overlords will vanquish them and feed them to Roko's basilisk. Seriously, people worry about this?
(Score: 2) by FatPhil on Saturday August 19 2017, @11:45AM (1 child)
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2) by stormwyrm on Sunday August 20 2017, @01:20AM
Numquam ponenda est pluralitas sine necessitate.
(Score: 0) by Anonymous Coward on Saturday August 19 2017, @08:13AM
Thus Voyager has saved the Earth. What we should be looking for is a close-by system similar to our own Solar System that one night "mysteriously" goes supernova. Ah, then SETI may have a datapoint. But if there are aliens, they would trust GPS coordinates, even given on a golden disc.
(Score: 2) by wonkey_monkey on Saturday August 19 2017, @05:36PM
The Pioneer plaques and the Voyager record did include such additional information.
systemd is Roko's Basilisk