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"Rebooted" Satellite Loses Thruster Capability:

An ambitious plan to revive a forsaken NASA satellite and return it to Earth orbit ended in disappointment Wednesday when engineers conceded that a failure in the spacecraft’s propulsion system made it impossible to fire thrusters and alter the probe’s flight path.

"There’s only so much you can do before you have to say, ‘It’s dead, Jim,’ " said Keith Cowing, a former NASA astrobiologist and a spokesman for the privately-run ISEE-3 Reboot Project, which operates out of a converted McDonald’s restaurant at NASA’s Ames Research Center in Mountain View, Calif.

Related story:Mechanical 'hiccups' complicate satellite reboot mission

Unable to nudge the aging probe from its orbit around the sun, project engineers say they have switched the spacecraft to “science mode” and will collect data from it for as long as they can — perhaps a couple of months.

NASA launched the International Sun-Earth Explorer 3 in 1978 to study space weather and retired it 17 years ago. As the spacecraft neared Earth on a pre-arranged flyby set for Aug. 10, Cowing and others won permission to take control of the craft, the first time NASA has ever handed over one of its assets to a private group.

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In just three months, the team of former NASA employees, engineers and self-described space cowboys managed to raise $160,000 on crowd-funding websites; wake the probe from an electronic slumber; communicate with it using the massive radio telescope in Arecibo, Puerto Rico; and fire several of its engines.

But the thrusters stopped working Tuesday, just as the team prepared to maneuver the spacecraft into a new orbital path.

On Wednesday, members of the ISEE-3 Reboot Project spent two hours attempting to diagnose the problem by “jiggling” fuel valves on and off. When the thrusters still failed to work, the disappointed engineers concluded that the satellite’s fuel system had lost critical pressure.

"We have exhaustively tested the propulsion system with no good results," project member Dennis Wingo, the chief executive of Skycorp Inc., reported on Twitter.

I’ll know where it is in the sky and at what time, and I’m just going to look up and wave goodbye to my old friend.- Bob Farquhar, member of the ISEE-2 Reboot Project

The satellite, like many others, uses hydrazine fuel. The highly toxic substance is stored in eight tanks and kept under pressure by nitrogen gas. When ground controllers instruct the satellite to open a fuel valve, the gas is supposed to push the hydrazine through fuel lines and into a catalyst. When it reaches the catalyst, the hydrazine should break down and produce an invisible puff of hot gas that propels the spacecraft.

Reboot engineers calculated that it would take about 432 puffs of gas to redirect the spacecraft into Earth orbit. But without fuel pressure, the thrusters will not fire.

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Cowing said it was possible there was a minute leak that allowed the gas to escape slowly — maybe even a molecule at a time — over decades. “There may still be some stuff in there; it’s just not enough,” he said.

The thruster firings that did occur were probably the result of residual gas pressure in the fuel lines, he said.

Since ground controllers were able to fire the thrusters initially, the satellite’s flight path has been slightly changed, and there’s a small chance that it may be on a collision course with the moon.

A lunar collision, they noted, would provide scientists with more data than they would collect in a normal flyby.

Related story: Space monkeys: The humanizing of Able and Baker

Reboot project engineers hope to determine the spacecraft’s exact location and new trajectory on Friday, when they will have access to NASA’s Deep Space Network, its powerful telecommunications system.

The propulsion system failure surprised one of the chief architects of the satellite’s orbital path, Bob Farquhar. The former NASA engineer helped send the satellite into space 36 years ago and charted a complex course that allowed it to become the first spacecraft ever to pass through a comet’s tail.

Farquhar was among the engineers working on the reboot project, and although he was highly skeptical they would pull it off, he said he never anticipated an equipment malfunction.

"I always thought the spacecraft would work OK," Farquhar said. "I can’t understand why all the nitrogen would be gone."

The 82-year-old had lobbied NASA for years to reactivate the satellite. He often said he had a supernatural connection to the spacecraft — a belief he developed when he suffered a heart attack at almost the same time ISEE-3 lost function of its only battery.

"I feel deflated," Farquhar joked Wednesday. "I think I’m losing pressure in my lungs."

Despite the failure, Farquhar said he planned to mark the spacecraft’s flyby next month.

"I’ll know where it is in the sky and at what time, and I’m just going to look up and wave goodbye to my old friend," he said.

Found: Most Distant Stars In The Milky Way Galaxy:

Astronomers have discovered the farthest-flung stars yet known in the Milky Way.

The two objects — known as ULAS J0744+25 and ULAS J0015+01 — are about 775,000 and 900,000 light-years from Earth, respectively, making them both about five times more distant than a satellite galaxy known as the Large Magellanic Cloud.

"The distances to these two stars are almost too large to comprehend," study lead author John Bochanski, of Haverford College in Pennsylvania, said in a statement. "To put it in perspective, when the light from ULAS J0015+01 left the star, our early human ancestors were just starting to make fires here on Earth."

The Milky Way extends far beyond its familiar disk, which is just 100,000 light-years or so wide. The galaxy is surrounded by a sparse “halo” of stars — perhaps stragglers left out there after the Milky Way’s many mergers with dwarf galaxies over the eons, researchers say.

Scientists know this halo extends to at least 500,000 light-years away, but its exact dimensions are unknown. Bochanski and his colleagues decided to probe the halo’s outer reaches, hunting for a type of star called cool red giants.

Distant Milky Way Star Uniview by SCISS Data: SOHO (ESA & NASA), John Bochanski (Haverford College) and Jackie Faherty (American Museum of Natural History and Carnegie Institute’s Department of Terrestrial Magnetism)

This simulated image demonstrates how small the Milky Way would look from the location of ULAS J0744+25, nearly 775,000 light-years away. 

Cool red giants are much rarer than red dwarfs, which make up about 70 percent of the Milky Way’s stars. But they’re about 10,000 times brighter, making them much easier to see from a distance.

"It really is like looking for a needle in a haystack," Bochanski said. "Except our haystack is made up of millions of red dwarf stars."

Astronomers watching a supernova may have found out where the dust that makes up much of the Universe came from.

Cosmic dust is crucial to the birth of stars and rocky planets, and provides the elemental ingredients for life. But its origin is obscure. Many astrophysicists think that dust is forged during the explosive supernova deaths of massive, short-lived stars, yet some observations of supernovas near our galaxy indicate that they produce too little material to account for the copious amounts of dust present in the young Universe.

In Nature today, astronomers lift the veil on the mystery, documenting the formation of dust in a supernova from just a few weeks after the explosion to almost 2.5 years after it. The study reveals the formation of oversized dust grains that were able to withstand the shocks of the exploding star. It also shows that dust production was slow at first, but later sped up.

Most previous studies looked at each supernova for short periods of time, so “they did not tell us the full story of how much dust supernovas produce”, says co-author Christa Gall, an astrophysicist at Aarhus University in Denmark. She and her colleagues monitored the supernova SN 2010jl, first spotted in a nearby galaxy in 2010.

Light and heat

Using a spectrograph on the Very Large Telescope on Cerro Paranal in Chile, the team measured the amount of visible light absorbed by the dust particles and the infrared radiation that the particles themselves emitted.

The team’s data are particularly compelling because they provide this simultaneous coverage at a range of wavelengths from weeks to years after the explosion, says astronomer Rubina Kotak of Queen’s University Belfast, UK. This provides information about both the size and the composition of the grains.

Such coverage “is difficult to obtain for all but the nearest and brightest supernova events”, she says.

The team concluded that the dust present between 40 and 240 days after the explosion must have been made of material expelled before the star went supernova, because the only other possibility would be the debris hurled into interstellar space by the supernova itself. And this is too hot to condense into dust particles so soon after the explosion, Gall notes. As the expanding shock wave from the supernova swept by in this period after the explosion, it compressed the previously ejected material into a cold, dense shell — the perfect environment for dust to coalesce and grow.

Resistant to shockwaves

To their surprise, the astronomers found that the dust particles were enormous by Milky Way standards, measuring 1 to 4.2 micrometres across — at least four times the typical width of dust particles found between star systems in our home Galaxy. It is harder to form large dust particles, notes Gall, but their size makes them resistant to destruction by shocks associated with the supernova slamming into interstellar material, and probably accounts for their longevity. Large interstellar dust grains have previously been found in our Solar System.

During early observations, the amount of dust around SN 2010jl was relatively small, equivalent to less than one-ten-thousandth the mass of the Sun. But between 500 and 868 days after the explosion, dust formation accelerated and the dust mass increased more than 10-fold.

The revved-up rate marks a transition to a second phase in supernova dust production, says Gall. Once carbon-rich material and other debris generated during the supernova has cooled sufficiently, it begins to coalesce into dust, speeding up production. At day 868, the last time Gall’s team observed the supernova, the amount of dust had increased to 0.04 of the Sun’s mass, or 830 Earth masses.

If the increased dust production continues, in 20 years SN 2010jl will have produced the equivalent of half the Sun’s mass in dust particles, similar to the amount observed in the widely observed supernova SN 1987A. If numerous supernovae early in the Universe produced dust at a similar rate, it could indeed account for the dust observed in the young cosmos, says Gall.

(Source: The Huffington Post)

The Awesome Beauty Of M16, The Eagle Nebula:

The Eagle Nebula, also known as Messier 16 or M16, consists of a star cluster and many emission nebulae and dark nebulae, in the direction of the constellation Serpens. It’s the location of several famous structures including the Pillars of Creation, whose photo you see in this post. Take a look at the photos here, and delve deeper into this region of space, which is one of the most interesting and beautiful we know.

View larger. | Behold the awesome beauty of

View larger. | Behold the awesome beauty of the Eagle Nebula, aka M16. Photo by Martin MacPhee.

Chart showing location of M16, or Eagle Nebula, via Tammy Plotner and Universe Today.

If you can find the famous Teapot asterism of the constellation Sagittarius, look for the Eagle Nebula, or M16, just a bit above and to the left of it, as viewed from a N. Hemisphere location. Chart via Tammy Plotner and Universe Today.

In the late 18th century, when this object began to be catalogued by astronomers, only the star cluster could be seen, and this was designated as M16 in Messier’s catalog of things not to be confused with comets. Later, this star cluster became known as the Snow Queen Cluster.

The advent of astrophotography revealed a large area of glowing hydrogen gas that was invisible to the unaided eye, and that looked somewhat like an eagle with outstretched wings, giving rise to the current common name of Eagle Nebula.

As higher resolution photography and then digital photography began to reveal more and more features, particularly the dark patches (aka dark nebulae), many distinct features within the Eagle Nebula were given individual names. Today, the informal name of the Eagle Nebula is taken as referring to all of these in one collective designation. Some of them are famous, and all are beautiful.

This is a 1995 photo of what has come to be called The Pillars of Creation.  It's located within the Eagle Nebula.

This is a 1995 Hubble photo of the Pillars of Creation. It’s one of the most famous photos ever taken by the Hubble Space Telescope. This feature is located within the Eagle Nebula.

View larger. | The Eagle Nebula suddenly burst upon the World's collective consciousness in 1995, when the Hubble telescope focused its attention on the dark nebula in the center of the Eagle, which you can see in this view. The dark protrusions of dense gas were found to be the site of new star and solar system formation, and the resulting photograph became known as

View larger. | A closer look at the Eagle Nebula. Photo by Martin MacPhee.

The Eagle Nebula suddenly burst upon the world’s collective consciousness in 1995, when the Hubble Space Telescope focused its attention on a dark nebula in the center of the Eagle, which you can see in the photos above and below.

The dark protrusions of dense gas were found to be the site of new star and solar system formation, and the resulting photograph became known as the Pillars of Creation and gave most people their first view of new stars and solar systems at the dawn of their creation.

Similar areas, such as the Stellar Spire on the left side of the Eagle, are also forming new stars, through a combination of processes. The cold, mostly hydrogen, gas of the nebula has already fueled the formation of a series of young, hot stars. As the gas continues to collapse under its own gravity into the dark forms we see, new stars and solar systems are formed and continue to grow as they attract more and more gas to them. However, the intense light pressure from the new stars that have formed and their solar winds are eroding away the dense, cold gas pockets, diminishing new star formation and dispersing the nebulae.

At the same time however, the shock waves where the light and solar wind impacts the cold gas, heat and compress some of the cold gasses at the same time, resulting in a new set of star forming environments

View larger. | Here is a labelled map showing both the

View larger. | Labelled map showing both the Pillars of Creation and the Stellar Spire, within the Eagle Nebula. Photo and labels by Martin MacPhee.

I am very pleased I can see these structures in my ‘scope, which is only 8″ in diameter, especially given that they are located around 7,000 light-years away, and the Stellar Spire is roughly 9.5 light-years (~ 9 trillion kilometers) tall – about twice the diameter of our solar system. In seeing them from my driveway in the heavily light-polluted Maryland suburbs of Washington D.C., I’m doing very well. And for approximately $10,000,000,000 less than the Hubble telescope cost, which makes my wife very happy too!

Enjoy the view while you can. Sadly, data from other telescopes has shown that the Pillars and Spire are likely already gone, victims of a massive shock wave from a supernova explosion that happened 8,000 to 9,000 years ago. Its light has already gone past us, but the slower-moving shock waves would have taken thousands of years more to sweep through the Eagle Nebula, destroying the delicate structures we find so entrancing.

The light of that destruction is already on its way to us, so in a few thousand years, people will be seeing a very different Eagle in the ever-changing sky.

Stellar Spire, also located in the Eagle Nebula, as seen by the Hubble Space Telescope.

Stellar Spire, also located in the Eagle Nebula, as seen by the Hubble Space Telescope.

Bottom line: What we know today as the Eagle Nebula, or M16, once was thought to be a simple star cluster. Astrophotography revealed the structure that resembled an eagle and gave the Nebula its current name. The Hubble Space Telescope revealed even more detail, so that today the Eagle Nebula is known as home to at least two famous structures: the Stellar Spire and the Pillars of Creation.

(Source: earthsky.org)

Big Pic:  A Portrait Of Saturns Best Features:

Like a photo of the New York City skyline with both the Empire State and Chrysler buildings in view, this image of Saturn shows off its most iconic landmarks. There’s the hexagon-shaped jet stream feature at its north pole, plus its rings. The spacecraft Cassini took this image on April 2.

Cassini recently celebrated the tenth anniversary of its arrival at Saturn. Now, its engineers are looking toward its final missions. In 2015, NASA plans to send Cassini to sample the water geysering out of Saturn’s moon Enceladus. This will be humanity’s first and only sample of that alien water. Then, in late 2016, Cassini will begin a series of 22 orbits around Saturn that will send the spacecraft between Saturn’s upper atmosphere and its innermost rings. Such close encounters with the planet will help scientists measure Saturn’s magnetic field and the mass of Saturn’s rings—another first.

illustration showing the orbits NASA plans for Cassini in its Grand Finale mission
The 22 orbits Cassini will make around Saturn in its final mission
NASA/JPL-Caltech

Finally, Cassini will plunge into Saturn’s atmosphere to avoid contaminating the planet’s moons, which scientists think may harbor alien life.

Supermassive Black Hole In Galaxy Blasts Gas Out At Near Light Speed:

Astronomers at University of Sheffield say they’ve solved a long-standing mystery in astronomy, related to the way galaxies evolve. They say their new insights deepen our understanding of the future of our own Milky Way galaxy. Using the ESO Very Large Telescope in Chile, they’ve found that the molecular hydrogen gas in the relatively nearby galaxy IC5063 is moving at extraordinary speeds – 1 million kilometers per hour – at the galaxy’s center. A supermassive black hole at the center of this galaxy is thought to be driving this outflowing gas. The work is published online in the July 6, 2014 issue of the journal Nature.

It relates to galaxy evolution because the gas being expelled is cold gas, which is required to form new stars. When galaxies expel gas in this way, the rate of star formation may become limited, inhibiting the galaxy’s evolution. All of this has been part of astronomical knowledge for some time, with outflows of gas from the centers of galaxies acting a key ingredient in theoretical models of the evolution of galaxies. The mystery has surrounded how the gas is accelerated.

This new study provides the first direct evidence that the molecular outflows are accelerated by energetic jets of electrons that are moving at close to the speed of light. Such jets are propelled by the central supermassive black holes. Clive Tadhunter, who led the research, said:

Much of the gas in the outflows is in the form of molecular hydrogen, which is fragile in the sense that it is destroyed at relatively low energies. I find it extraordinary that the molecular gas can survive being accelerated by jets of highly energetic particles moving at close to the speed of light.

These astronomers say these findings help us further understand the eventual fate of our own galaxy, the Milky Way, which will collide with neighboring galaxy Andromeda in about 5 billion of years.

They say that – when this collision of galaxies occurs – gas will fall to the center of the remnant of the collision. Meanwhile, the jets coming from the central supermassive black hole will, in a way similar to what is now observed in IC 5063, eject the gas from the system, preventing the formation of new stars and growth of the newly formed galaxy.

Bottom line: Astronomers at University of Sheffield used the ESO Very Large Telescope in Chile to discover molecular hydrogen gas in the galaxy IC5063 is moving at extraordinary speeds – 1 million kilometers per hour – at the galaxy’s center. A supermassive black hole at the center of this galaxy is thought to be driving this outflowing gas. Because this process expels cold gas from the galaxy, and because cold gas is needed to form new stars, the astronomers say they’ve gained insight into the process by which galaxies evolve. They’ve extrapolated this insight to reveal something of our own Milky Way galaxy’s future.

(Source: earthsky.org)

Supermassive Black Hole
The supermassive black holes in the cores of some galaxies drive massive outflows of molecular hydrogen gas. As a result, most of the cold gas is expelled from the galaxies. Since cold gas is required to form new stars, this directly affects the galaxies’ evolution. These outflows are now a key ingredient in theoretical models of the evolution of galaxies, but it has long been a mystery as to how they are accelerated.
 The study provides the first direct evidence that the molecular outflows are accelerated by energetic jets of electrons that are moving at close to the speed of light. Such jets are propelled by the central supermassive black holes. Using the ESO Very Large Telescope in Chile to observe the nearby galaxy IC5063, the researchers found that the molecular hydrogen gas is moving at extraordinary speeds - 1 million kilometers per hour - at the locations in the galaxy where its jets are impacting regions of dense gas.
 These findings help us further understand the eventual fate of our own galaxy, the Milky Way, which will collide with neighbouring galaxy Andromeda in about 5 billion of years. As a result of this collision, gas will fall to the centre of the remnant of this collision, but the jets coming from the central supermassive black hole will, in a way similar to what is now observed in IC 5063, eject the gas from the system, preventing the formation of new stars and growth of the newly formed galaxy. Clive Tadhunter, from the University’s Department of Physics and Astronomy, said: “Much of the gas in the outflows is in the form of molecular hydrogen, which is fragile in the sense that it is destroyed at relatively low energies. I find it extraordinary that the molecular gas can survive being accelerated by jets of highly energetic particles moving at close to the speed of light.” “We suspected that the molecules must have been able to reform after the gas had been completely upset by the interaction with a fast plasma jet.” says Morganti “Our direct observations of the phenomenon have confirmed that this extreme situation can indeed occur. Now we need to work at describing the exact physics of the interaction”. The results are published in Nature on the 6th of July and they are connected to the project ‘Exploiting new radio telescopes to understand the role of AGN in galaxy evolution’, for which Morganti received from the European Research Council an Advanced Grant of 2.5 Meuro last year.
 Caption: Netherlands Institute for Radio Astronomy

  NASA/ESA and the Hubble Space Telescope archive.

NASA Equips Space Robots With Smartphones:

Nasa plans to send Google’s 3D smartphones into space to function as the “eyes and brains” of free-flying robots inside the Space Station.

The robots, known as Spheres (Synchronised Position Hold, Engage, Reorient, Experimental satellites), currently have limited capabilities.

It is hoped the smartphones, powered by Google’s Project Tango, will equip the robots with more functionality.

The robots have been described by experts as “incredibly clever”.

When Nasa’s robots first arrived at the International Space Station in 2006, they were only capable of precise movements using small jets of CO2, which propelled the devices forwards at around an inch per second.

"We wanted to add communication, a camera, increase the processing capability, accelerometers and other sensors," Spheres project manager Chris Provencher told Reuters.

"As we were scratching our heads thinking about what to do, we realised the answer was in our hands. Let’s just use smartphones."

In an attempt to make the robots smarter and of more use to astronauts, engineers at Nasa’s Ames Research Centre sent cheap smartphones to the space station, which they had purchased from Best Buy, an American electronics shop.

Astronauts then attached the phones to the Spheres, giving them more visual and sensing capabilities.

Helping astronauts

Looking to further improve the robots, Nasa turned to Google’s Project Tango.

Tango uses the 3D cameras embedded in Google’s latest smartphones to give the handset a human-scale understanding of space and motion.

Once at the space station and attached to the Spheres, the phones will use their onboard motion-tracking cameras and infrared depth sensors to safely navigate around the ISS.

These more advanced phones will be launched into space on 11 July and are intended to replace the earlier models.

Noel Sharkey, professor of artificial intelligence and robotics at the University of Sheffield, told the BBC: “This is an incredibly clever way to unite different technologies in an unexpected way.

"It will be interesting to see how much this inspires Google to use this technology for its own robotics development following on the several world-class robot companies it has purchased in the last year."

Dr Fumiya Iida, lecturer at the department of engineering at the University of Cambridge, praised Nasa’s ingenuity.

"Robots were and still are usually very expensive and complex, thus they often don’t match to a cost-benefit balance. By using consumer electronics such as smartphones, we can significantly reduce down the development cost for robots with high-performance capabilities which were not possible 10 years ago."

Nasa envisions a future in which its spatially-aware Spheres can help astronauts with daily chores and risky tasks.

Dr Walterio Mayol of Bristol University’s Robotics Lab told the BBC that the basic idea behind the mapping system, a technique known as Slam (simultaneous localisation and mapping), was developed substantially in the UK ten years ago.

He said that while the robots are an impressive start, they currently have no arms, which could limit their potential.

The Spheres’ creators are said to have been inspired by Luke Skywalker’s training droid, from the film Star Wars Episode IV: A New Hope, although it is unlikely lasers will be fitted to the device.

(Source: bbc.com)

NASA’s Zombie Spacecraft Learns To Fire Its Engines:

The quest to save the ISEE-3—a long-lost NASA probe launched in the disco era and abandoned in the dot-com boom—might just succeed. Late last week, the amateur scientists and engineers working to salvage the probe hit a major milestone: They coaxed the craft into firing its rotational thrusters. 

“We’re pretty much confident now that it’ll come close to the moon but not crash into it.”

The achievement is important for many reasons. While the amateur team trying to reboot the ISEE-3 has been in radio contact with the probe for more than a month, this is the first time it has successfully commanded moving parts onboard. It’s important for technical reasons. The ISEE-3 is “spin-stabilized,” meaning it only functions properly when it’s tumbling over itself. The team can now adjust that spin.

And, finally, it’s important for planning reasons. Now, the team can begin to fire the ISEE-3’s thrusters and change the ship’s trajectory—hopefully, keeping it from crashing into the moon.

Keith Cowing, a journalist-turned-mission-leader, told me that they hoped to begin changing its course on Tuesday. “We’re pretty much confident now that it’ll come close to the moon but not crash into it,” he said.

Launched in 1978, the International Sun/Earth Explorer-3 first served for years as a solar observatory, sitting at a stable orbit point between the Earth and the Sun. By 1986, NASA had replaced the aging craft with superior sensors. They determined it didn’t need to occupy its stable position, so they piloted it through the tails of Comet Giacobini-Zinner and Halley’s Comet. The ISEE-3 was renamed ICE, the International Comet Explorer.

And then scientists decided they didn’t need it at all anymore. A NASA engineer directed the probe into a long, looping orbit, far around the sun, that would place it back in Earth’s vicinity around 2014.

That date has now arrived, but NASA won’t be the one monitoring ISEE-3. The agency abandoned the machinery needed to control and talk to the craft in 1997.

Instead, on August 10, 2014, the probe will pass just above the surface of the moon, and a group of amateurs led by Cowing and space engineer Dennis Wingo will be paying close attention. They put together the documentation, the engineering know-how, and the radio telemetry equipment needed to pilot the craft out of harm’s way.

The reboot mission had originally hoped to change the ISEE-3’s course weeks ago. When we first talked, Cowing told me that if they hadn’t begun firing its thrusters by July, he’d be nervous. But it turns out the probe wasn’t where it first seemed. “Initially, our calculations were based on old data, which showed the spacecraft not being where it was supposed to be,” Cowing said. “But we did a lot of ranging with NASA’s giant dishes—it’s a lot closer to where we thought it’d be.”

That means that they can expend less fuel putting it on a new trajectory, so the critical maneuver they’ve been planning can happen later. They’ll have more time to change the probe’s course without having to worry about the gravity of the Earth or moon pulling it onto their surfaces.

In the past month of working with the spacecraft, Cowing said they’d gotten used to its idiosyncrasies. ISEE-3 lacks an onboard computer, so commands must be fed to it one at a time. Cowing compared the process to rock-climbing: When it’s time to move to the next outcrop, the movement has to happen quickly and definitively.

“You just have to push through it and the data you get back isn’t exactly what you want. As soon as it would take another command, you just rush through the next one and the next one,” he said.

“It’s like telling an old dot-matrix printer from back in the day to do something.”

(Source: The Atlantic)

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