Voyager 2 spacecraft resumes its exploration of interstellar space after NASA engineers fix a potentially fatal glitch from 11.5 billion miles away
- NASA says Voyager 2 officially entered ‘interstellar space’ in November 2018
- At the end of January there was an energy spike due to a failed spin manoeuvre
- It shut off its science instruments but NASA engineers remotely turned them on
- It took 34 hours for the engineers to find out if it worked due to the fact it takes 17 hours for light to reach Voyager 2 which is 11.5 billion miles away
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The Voyager 2 spacecraft is able to resume its exploration of interstellar space after NASA engineers fixed a potentially fatal glitch from 11.5 billion miles away.
The craft has been measuring the density of the plasma in interstellar space since it first left the solar system in November 2018.
On January 28 Voyager 2 failed to execute a spin manoeuvre and systems on the explorer remained active for longer than planned.
This resulted in them using so much energy that Voyager automatically shut off its science instruments to safeguard power.
NASA engineers worked to fix the problem remotely and, on Wednesday 5, the science gear on the probe was up and gathering data again.
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This artist’s concept depicts one of NASA’s Voyager spacecraft entering interstellar space, or the space between stars. Interstellar space is dominated by the plasma, or ionized gas, that was ejected by the death of nearby giant stars millions of years ago.
Mission operators for NASA say it is stable and communications between Earth and the spacecraft are good.
It is taking science measurements again and the team are evaluating the health of the instruments after the ‘brief shut off’.
Voyager 2 is now 11.5 billion miles from the Earth and, at that distance, light takes 17 hours to reach it or for messages from it to reach mission control on Earth.
That means that engineers had to wait a total of 34 hours to find out if the fix they implemented had worked.
Voyager gets its power from a radioisotope thermoelectric generator (RTG) which turns heat from the decay of a radioactive material into electricity.
Because of the way it uses the decay of the material, the power budget for the craft drops by about four watts per year.
Mission control are turning off certain systems to keep it operating as long as possible including turning off the primary heater for the cosmic ray subsystem instrument – that instrument is still operating without the heater.
Because of the gradual loss in power when there is a spike in demand for energy it powers off science instruments to make up the difference.
Despite the fault, Voyager 2 continued to move and the engineers on Earth were able to remotely re-power the instruments.
Voyager 2’s journey took it beyond the Sun’s protective bubble — dubbed the ‘heliosphere’ — and out into the wider cosmos in the November of last year. Despite launching 16 days before its twin spacecraft, Voyager 1, it took six years longer to reach the interstellar medium
The probe left the Earth more than 42 years ago on a mission to study the outer planets and is expected to finally run out of power by the mid-2020s.
It was part of a pair of spacecraft, launching a few weeks after its sister, Voyager 1 which left the solar system in 2012.
Voyager 2 was later than its sister in entering interstellar space as it spent longer studying the outer planets, including becoming the first and only spacecraft to visit the ice giant’s Neptune and Uranus.
Launched in 1977, Voyager 1 and Voyager 2 are now known as interstellar probes, making them the most distant human-made objects in the solar system.
Interstellar space, or the ‘space between the stars’, is dominated by the plasma that was ejected by the death of nearby giant stars millions of years ago.
That plasma is what the two Voyager probes are now measuring.
WHERE ARE THE VOYAGERS NOW?
Voyager 1 is currently 13 billion miles away from Earth, travelling northward through space.
The probe has recently sent back data to Nasa that cosmic rays are as much as four times more abundant in interstellar space than in the vicinity of Earth.
This suggests that the heliosphere, the region of space that contains our solar system’s planets, may act as a radiation shield.
Where they are: This graphic shows where our solar system’s final frontier, the heliosheath, fits in relation to our galaxy. The interstellar wind collides with the heliosheath and forms a structure called the bow shock (red and orange areas, forcing the heliosheath into a long, teardrop shaped structure. Voyager 1 has reached the final frontier of our solar system, having travelled through a turbulent place where electrically charged particles from the Sun crash into thin gas from interstellar space.
Meanwhile, Voyager 2 is now 11.5 billion miles from Earth, travelling south towards the interstellar region.
The contrasting locations of the two spacecraft allow scientists to compare two regions of space where the heliosphere interacts with the interstellar medium.
Voyager 2 crossing into the interstellar medium allows scientists to sample the medium from two different locations at the same time.