Humans have now spent a full decade exploring interstellar space.
August 25, 2012, NASA’s Voyager One The spacecraft is 11 billion miles (18 billion kilometers) from the sun, and scientists have determined that the ancient spacecraft has crossed the boundary between the sun’s influence and the interstellar medium.Now Voyager 1 and its twin continue to send data back Voyager 2 – Joined Interstellar in 2018 – Continuing groundbreaking science.
Voyager 1 and Voyager 2 were launched in 1977 to explore Jupiter and Saturn. Voyager 2 also visited Uranus and Neptune, while Voyager 1 prioritized Saturn’s giant moon Titan, which sent it into a new orbit to the edge of Earth. solar systemVoyager’s interstellar mission was not created until after Voyager 2’s flyby of Neptune in 1989.
“No one expected Voyager to leave the interstellar medium,” Merav Opher, an astronomer at Boston University who runs a center called SHIELD that is re-examining sailing, told Space.com data from the Heliosphere to learn more about the heliosphere. “They have five years of life, another five years, then ten years, but no one really thought they would leave the solar system.”
Gemini spacecraft’s discovery of the heliosphere — the magnetic bubble around us — could have implications for our understanding of life on Earth Earth.
related: Celebrate Voyager’s 45th Anniversary with These Stunning Solar System Images (Gallery)
Voyager 1’s interstellar moment
Voyager 1 became the first man-made object to explore interstellar space – the space between stars in a galaxy – when it was 122 astronomical unit (AU) away from the sun. (One AU is the average distance between the Earth and the Sun, which is roughly equal to 93 million miles or 150 million kilometers.)
Scientists are confident that the Voyager probe has crossed from the heliosphere — the solar wind is the stream of charged particles from the solar wind. sunwhich dominates due to particle density – into interstellar space.
“At these distances, the density is 10 times what we find in the solar wind,” Opher said of the late 2018 reading. Voyager 1 is out.
Voyager 2’s instruments detect the same jump in particle density it entered interstellar space November 5, 2018.
reveal the heliopause
The probe’s journey into interstellar space may be well-defined, but the heliopause — the “twilight zone” between the bubble-shaped heliosphere and interstellar space — has unexpected properties. Each spacecraft took several months to traverse, during which time they sent back data on peaks and valleys in plasma density.
“We expected it to beep, but the heliopause wasn’t like a line or a door—it was much thicker and more complex than we thought,” Ofer said. “But it’s also a boundary that allows communication.” The surprising discovery of particles moving in and out of the heliosphere came first from magnetic field data from Voyager 1 in 2012 and then from Voyager 2 six years later.
Voyager 1 and 2 data on the heliopause’s magnetic field baffled scientists.There should be a change where the magnetic field from the sun meets the magnetic field from space, which theorists expect galaxy Tilt toward the sun’s magnetic field. But neither Voyager 1 nor Voyager 2 detected a change in the direction of the magnetic field.
“When Voyager crossed, the angle didn’t change. The magnetic field was almost like the sun, with no rotation,” Ofer said. It’s still a mystery, but Opher and her collaborators have a theory about a magnetic flux tube in the heliopause that connects the solar and interstellar fields. “It’s almost as if there are these highways for particles to move in and out of the heliosphere,” she said, adding that this could be an area where the magnetic field reconnects.
The heliopause appears to be the curved surface of the heliosphere that responds to solar activity, but why remains an open question.
beyond the heliopause
Voyager 1 is now 40 AU from the heliopause, allowing scientists to discover what the interstellar medium really looks like. It turns out that it is much more influenced by the heliosphere than previously thought. “The interstellar medium measured by the Voyager probe is not quiet, it is churned and influenced by the sun,” Ofer said. “It’s completely different from what we expected and we still don’t understand what happened.”
The data show that galactic cosmic rays behave differently depending on whether they are parallel or perpendicular to the Sun’s magnetic field. “We thought we would see galactic cosmic rays coming from all directions, but they didn’t,” Ofer said.
These data can be correlated with coronal mass ejections (CMEs) from the sun, which cause disturbances in the distant interstellar medium in their magnetic fields. This has forced scientists to rethink how cosmic rays reach Earth.
what’s next for navigator
This”silent ambassador“Eventually, when they enter what scientists call the primordial interstellar medium, they quiet down. As the Sun’s influence fades and the turbulence decreases, probes may pick up mixtures of matter from other stars.
However, the impact of detecting the next star is beyond the scope of the spacecraft.Voyager 1 will approach a star called AC+79 3888 in the Camelopardalis constellation 40,000 years later Voyager 2, on the other hand, flew about the same time as a star in the constellation Andromeda called Ross 248.
Now there are two ships end of its useful life With their power drained, the last time scientists hear from them could be best in the 2030sthe mission staff said.
For scientists studying the heliosphere, the next spacecraft of interest will be New Horizons, the spacecraft that photographed Pluto in 2015. New Horizons will enter the heliopause around 2030, but its power supply won’t last until the late 2030s.At the same time, scientists are considering interstellar probea decades-long mission to study the heliosphere to build on Voyager’s discoveries.
Voyagers and the search for life
“Nothing reveals a new world like field data, and Voyager has played a major role in redefining our understanding of the heliosphere,” said Ofer, who believes the heliosphere protects life on Earth from Harmful cosmic rays and dust damage. She also believes that the position of the solar system in the interstellar medium is crucial for nurturing life.
“If we’re going to try to find life on other planets, the only habitable celestial body “We have our own control. Voyager revealed its complexity,” Ofer said.
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