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Home / Science / NASA has discovered how travelers' lives can be extended even longer

NASA has discovered how travelers' lives can be extended even longer



The Voyager 1 and 2 are 42 years in space and still in operation. And although they are 18 billion kilometers from the sun, they are scientifically valuable. But they run out of energy, and if NASA wants them to go on much longer, they'll have to make some decisions.

The Energy Problem

The energy problem becomes more and more critical for the Voyager over time. Their scientific instruments not only need energy, but the spaceships must also keep warm in the cold environment of space. The two spaceships are not solar powered: this would not be possible near the sun. Their energy is based on thermoelectric radioisotope generators (RTG).

Each of the Voyager probes has three RTGs and uses plutonium 238 as the fuel source. When this isotope decays, heat is created which is converted into electrical energy. Each Voyager started with a power of 470 watts at 30 volts DC, which however deteriorated over time. Not only is the fuel constantly consumed, but the thermocouples used in the system get worse over time. As of 201

1, both Voyager produced just under 270 watts, which is about 76% of the power they started with.

  A pellet of plutonium 238, the isotope used to propel the RTGs of both Voyager spacecraft. When decaying the pellets give off heat, which is why they glow red. Picture credits: Los Alamos National Laboratory.
A pellet of plutonium 238, the isotope used to propel the RTGs of both Voyager spaceships. When decaying the pellets give off heat, which is why they glow red. Picture credits: Los Alamos National Laboratory.

Although these 270 watts are better than predicted when the probes were designed and launched, it still means that inevitable decisions must be made about which spacecraft systems to shut down.

First, you must pay NASA the honor of keeping the probes running for so long. It is amazing in itself. Some parts of the probes are already off and remarkably still working.

In response to energy issues, NASA shut down the heater for the Voyager 1 UV spectrometer in 2011. This instrument was designed to operate at temperatures as low as -35 degrees Celsius (-31 degrees Fahrenheit). However, after turning off the heater, it continued to operate at -79 degrees Celsius (-110 degrees Fahrenheit).

"It's unbelievable that Voyagers' instruments proved so robust.

Voyager Project Manager Suzanne Dodd

But that was in 2011, and RTGs have lost even more power since then. In fact, they lose about 0.8% of their power each year. Now, NASA engineers sharpen their slide rules and create a new energy management plan to keep the probes up and running longer.

Turn off the heater to keep the Voyager running

Recently, NASA decided to turn off the heater for another instrument, this time for Voyager 2. You have the heater for the Cosmic Ray Subsystem (CRS) Voyager 2 turned off. , That's too bad, because in November 2018, the CRS instrument was critical to Voyager 2's departure from the heliosphere and its entry into interstellar space. Since the probes left the heliosphere, they send us unique and important information about how the heliosphere interacts with the interstellar wind. No other spacecraft can do that, and it would take decades to install another.

  Voyager 1 and 2 both left the heliosphere and are the first spacecraft to do so. Photo credits: NASA / JPL-Caltech - https://photojournal.jpl.nasa.gov/figures/PIA22835_fig1.png, Public Domain, https://commons.wikimedia.org/w/index.php?curid=74978307 [19659016] Voyager 1 and 2 both left the heliosphere and are the first spaceships to do so. Photo credits: NASA / JPL-Caltech - https://photojournal.jpl.nasa.gov/figures/PIA22835_fig1.png, Public Domain, https://commons.wikimedia.org/w/index.php?curid=74978307 [19659007] Although the instrument heater for Voyager 2's Cosmic Ray Subsystem (CRS) has been turned off, the engineers have confirmed that the instrument still operates at -59 degrees Celsius, even though they have been tested down to -74 degrees Celsius only. 45 C (-49F.) </p>
<p>  "It's unbelievable that Voyager's instruments have proven to be so robust," said Suzanne Dodd, project manager for Voyager, who works at NASA's Jet Propulsion Laboratory in Pasadena, California. "We are proud that they have withstood the test of time, and because of the spacecraft's long lifespan, we are dealing with scenarios we never thought would happen to them, and we will continue exploring all possibilities that exist we've got to keep the Voyager up to date with science. "</p>
<p>  At the present time, Voyager 2 still retains data from five instruments, even though the CRS was turned off, in particular, it still heats up the low-energy particle analyzer This is because data can be returned in the transition from the heliosphere in the same way as in CRS The CRS is unidirectional, while the low energy instrument is omnidirectional, which is one of the reasons why CRS heating was turned off </p>
<h2>  The delay of the inevitable </h2>
<p>  The generation of heat is an energy-intensive activity If probes wane, more heaters may need to be turned off to allow the remaining instruments to work. There's no way around it. The shrinking energy budget of the probes also affects systems other than scientific instruments. </p>
<p>  The probes have small thrusters and are critical to the operation of the probes. The spacecraft must be aligned with their antennas facing the earth so that they can receive orders and return data to Earth. Each spacecraft has a tank of hydrazine fuel used to power its small engines, working in tiny bumps or orbits to orient the spacecraft. </p>
<figure class=  In this illustration, NASA's Hubble Space Telescope observes the paths of NASA's Voyager 1 and 2 spacecraft as they travel through the solar system into interstellar space. Hubble looks at two lines of sight (the double-cone shaped features) on the path of each spacecraft. The objective of the telescope is to help astronomers map the interstellar structure along the star-bound route of each spacecraft. Each line of sight extends over several light-years to nearby stars. Picture credits: NASA, ESA and Z. Levy (STScI).
In this illustration, NASA's Hubble Space Telescope observes the paths of NASA's Voyager 1 and 2 spacecraft as they travel through the solar system into interstellar space. Hubble looks at two lines of sight (the double-cone shaped features) on the path of each spacecraft. The objective of the telescope is to help astronomers map the interstellar structure along the star-bound route of each spacecraft. Each line of sight extends over several light-years to nearby stars. Picture credits: NASA, ESA and Z. Levy (STScI).

If the lines supplying fuel to the engines were to freeze, engineers could not target the spaceship antennas or instruments. At this point, the spaceship would probably be unusable. So you also need heat.

However, there is another problem with the engines. Inevitably, such systems fail over time, and in 2017 the engineers found a problem. Some of the engines on Voyager 1 had to work harder to maintain proper alignment with the earth. So they turned to some unused engines to see if they could do the job.

Believe it or not, these secondary engines have not been used for 37 years. But they were exhausted and did their job. That must be a kind of record for itself.

  An illustration of Voyager 1. The set of four support engines is located in this orientation on the rear of the spacecraft. Photo credits: NASA / JPL-Caltech
A Voyager 1 illustration. The set of four spare engines are located in this orientation on the rear of the spacecraft. Credit: NASA / JPL-Caltech

Now the main engines of Voyager 2 are beginning to show problems. Due to the success they had with the old, unused engines of Voyager 1, the engineers decided to start the old backup engines on Voyager 2 as well. But they did not sleep as long as Voyager 1 existed. They were last used when Voyager met Neptune 30 years ago in 1989, and NASA plans to turn it on later this month.

With clever engineering, careful planning, and reasonable use of the remaining energy of both Voyager, the inevitable end of the spaceship is delayed. As a result, their ongoing scientific contributions can go on for a while into the future.

"Both Voyager probes explore regions that have never been visited before. Every day is a day of discovery. "

Ed Stone, scientist of the Voyager project.

Engineers and mission planners believe there will be a few years left to operate. This is important because everything we learn about the region of space they are in is based on their unique position to observe them. This is not to be underestimated as new papers are still being written based on Voyager data, not only where they are located, but also where they were years or decades ago. [2017] In 2017, the former chairman of the NASA External Planetary Assessment Group, Fran Bagenal, was interviewed in Nautilus. In this interview, she said, "I still analyze Voyager data, believe it or not, we just published three articles on Voyager data taken 33 years ago, and all of us are celebrating the 40th anniversary of Voyager data It was fun, and I realized that some of the data I used to write my diploma thesis in 1979 was not re-analyzed. "

The question is how many future articles will be based on current data in

Nothing Remains Forever

The most famous photos of the Voyager program are the Pale Blue Dot photos (actually a photo series) .We do not receive any more photos from the Voyager cameras But it's almost scary how these spaceships still provide data, unique data, so many decades after they were designed, built and launched, strangely they are like Time capsules of early space exploration technology.

  The Famous
The Earth's Famous "Light Blue Dot", taken by Voyager 1 in February 1990 (NASA / JPL)

"Both Voyager probes explore regions that have never been visited before, and therefore every day a day of discovery, "said Voyager project scientist Ed Stone, who is based at Caltech. "The Voyager will always surprise us with new knowledge about space."

Nothing lasts forever and one day it will be for the Voyager spacecraft. For people who know the missions and know what they have contributed to the knowledge of humanity, this is a sad day. It's strange to think about everything that happened here on Earth while the two spaceships started their journey.

The good news is that the future spaceships will be building on the work of the Voyager program the tiny IBEX probe. Picture credits: NASA "class =" wp-image-16062 "srcset =" https://www.universetoday.com/wp-content/uploads/2008/07/ibex__1.jpg 304w, https://www.universetoday.com /wp-content/uploads/2008/07/ibex__1-249×246.jpg 249w "sizes =" (max-width: 304px) 100vw, 304px "/>

An artistic impression of the tiny IBEX probe Source: NASA [19659007] NASA launches the Interstellar Mapping and Accelerator Probe (IMAP) in 2024 and will use Voyager's observations, and its Interstellar Boundary Explorer (IBEX) is already building on the work of Voyager 1 and 2 to provide more detailed information about the heliosphere. 19659004] In the same Nautilus interview, Fran Bagenal said, "I would predict that we will not be able to communicate with him in about 15 years." She is not an official spokesperson for the Voyager program, but if she's correct this means that communication may end by 2032.

Select this dat around in your calendar.

Draw attention to the nostalgia.

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