Home https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Science https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ What Voyager 2 learned after spending a year in interstellar space

What Voyager 2 learned after spending a year in interstellar space



Only two spacecraft of humanity have left the solar system: NASA Voyager 1 and Voyager 2. Voyager 1 left the heliosphere in 2012, while Voyager 2 did the same on November 5, 2018. Now Voyager 2 is in interstellar space space for one year, and five new papers present the scientific results of that one year.

The heliosphere is an area of ​​space in the form of a balloon with our Sun in the center. Think of it as an inflated cavity filled with plasma coming from the sun. The end of the bubble is where the plasma from our Sun gives way to the interstellar medium (ISM.) Voyager 2 left the heliosphere behind and entered the interstellar space about 18 billion km (11 miles) from Earth.

Each of the five documents contains the results of one of the five scientific instruments of Voyager 2:

  • magnetic field sensor
  • two instruments that detect energy particles in different energy ranges
  • two instruments that study plasma [Itisremarkablethatthesetoolsdesignedandbuiltdecadesagoarestillfunctioningandcollectingnewdata

    It takes decades for Voyager 2 to reach heliopause, the distinction between interstellar space and our solar system. As only the second spacecraft to reach it, Voyager 2 is able to give us unique scientific studies for the region. They are unique because Voyager 1

    left the heliosphere in a different place, six years before. Voyager 2 data is also unique, as one of its devices used for plasma measurement is still working while the Voyager 1 counterparty tool stopped functioning decades ago.

    <img src = "https://www.universetoday.com/wp-content/uploads/2019/11/1250px-Ibexheliosphererevised-1024×590.jpg" alt = "Illustration of an artist showing shock break, heliopause and radiation wool, Credit: Credit: NASA / IBEX / Adler Planetarium – Original text: https://www.nasa.gov/sites/default/files/thumbnails/image/ibexheliosphererevid.jpghttps://www.nasa.gov/ feature / goddard / 2016 / nasa-s-ibex-observations-pin-down-interstellar-magnetic field), Public Domain, https://commons.wikimedia.org/w/index.php?curid=6249685 snean19659010 picsAn & # 39 ; s artist illustration showing shock break, heliopause, and bow wave Credit: NASA / IBEX / Adler Planetarium – Original t kst: https://www.nasa.gov/sites/default/files/thumbnails/image/ibexheliosphererevid.jpghttps://www.nasa.gov/feature/ goddard / 2016 / nasa-s-ibex-observations-pin- down-star-magnetic field), Public Domain, https://commons.wikimedia.org/w/index.php?curid=62496851 runs on an 11-year cycle and its output changes during that cycle. There is debate about the overall shape of the heliosphere, but over the 11-year cycle, the size and shape may change. Each of the Voyager probes encountered heliopause at approximately the same distance, but Voyager 2 encountered the shock of terminating about 1 billion miles closer to the Sun than Voyager 1. The probes left the heliosphere at different locations, and each of the Voyager probes had something different to do. tell us.

    Currently, Voyager 2 is located in a transitional region of space at the end of the heliosphere, and not quite in undisturbed interstellar space.

    Ed Stone is a professor of physics at Caltech and a scientist on the Voyager program project. In a press release, he said: "The Voyager probes show us how our Sun interacts with things that fill most of the space between the stars in the Milky Way galaxy. Without this new data from Voyager 2, we would not know if what we see with Voyager 1 is specific to the whole heliosphere or specific to the location and time it passes. ”

     Voyager 1 left the heliosphere closer to the leading edge, while Voyager 2 left the heliosphere on the flank, 6 years later. Credit: NASA / JPL-Caltech - https://photojournal.jpl.nasa.gov/figures/PIA22835_fig1.png, Public Domain, https://commons.wikimedia.org/w/index.php?curid=74978307
    Voyager 1 left the heliosphere near the leading edge, while Voyager 2 left the heliosphere on the flank, 6 years later. Credit: NASA / JPL-Caltech – https://photojournal.jpl.nasa.gov/figures/PIA22835_fig1.png, Public Domain, https://commons.wikimedia.org/w/index.php?curid=74978307

    Voyager 1 left the heliosphere near the front as the solar system travels through space. Think of it as the nose of a ship. Voyager 2 left the heliosphere on the flank.

    Results

    Both Voyager probes told us that plasma in the local interstellar space is more dense than plasma inside the heliosphere. Scientists were expecting these findings. Now that Voyager 2 has left the heliosphere, we know that the same local interstellar plasma is also colder than the plasma inside the heliosphere.

    When Voyager 1 left the heliosphere behind in 2012, it measured plasma density just outside the heliosphere. and found it higher than expected. This indicates that it is being compressed. Voyager found that the same stretch of plasma was also warmer than expected, which also showed compression, although the outer plasma was still colder than the inner plasma.

    Voyager 2 also measures a slight increase in plasma density exactly in the heliosphere, indicating that its compression also. But for now, scientists have no explanation.

    <img src = "https://www.universetoday.com/wp-content/uploads/2019/11/1920px-PIA17046_-_Voyager_1_Goes_Interstellar-1024×570.jpg" alt = "Illustration by an artist about distances from the solar system. Note that the scale bar is increased by 10X astronomical units Image Credit: By NASA / JPL-Caltech – http://photojournal.jpl.nasa.gov/catalog/PIA17046, Public Domain, https: //commons.wikimedia .org / w / index.php? curid = 28366203 snean19659022] Artist's illustration of solar system distances Note that scale bar is enlarged by 10X astronomical units Credit: NASA / JPL-Caltech – http: // photojournal.jpl.nasa.gov/catalog/PIA17046, Public Domain, h ttps: //commons.wikimedia.org/w/index.php? curid = 28366203 records19659011] The data shows that the flank where Voyager 2 left the heliosphere may be somewhat "porous" compared to where Voyager 1 left. Voyager 2 has discovered a cluster of particles "leaking" from the heliosphere into the interstellar space.

    Voyager 1 found surprise when it left the heliosphere. The magnetic field just beyond the heliopause is parallel to the field inside the heliosphere. At the time, scientists could not say whether it was just an anomaly. But now Voyager 2 has found the same magnetic alignment.

    The Voyager probes were never intended to last that long. Their journey was remarkable and taught us a lot. Before reaching the heliopause, scientists thought the solar wind would fade gradually. But instead, we know that there is a more distinct boundary, indicated by a lower temperature and higher density.

    Voyager probes revealed other surprises. In 2011, we were shown that heliopause is not a smooth area. It contains magnetic bubbles that are likely to form when the sun's magnetic field is distorted at the end of the solar system.

    The end is within sight of the Voyager program. Eventually their strength will decrease. NASA intends to exclude tools one by one to extend the mission as long as possible. But sometime around 2025, the last instrument will run out of power. Then the Voyager probes will simply continue to follow their trajectory.

    What is their ultimate destiny, we will never know.

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