Voyager 2 enters the interstellar space after 42 years

The heliopause

It finally broke free from the Solar System to enter interstellar space a year ago, joining its twin companion Voyager 1, which exited in 2012. The edge of the heliosphere is called the heliopause.

Voyager 2 is the main priority for receiving new plans because it's collecting more data with an instrument that isn't working on Voyager 1.

"It's kind of like looking at an elephant with a microscope", Bill Kurth, also from the University of Iowa, said in the statement.

Comparing what Voyager 2 learned with the data available from the Voyager 1 crossing provides interesting similarities and contrasts, Stone said. When the data is taken together, it helps scientists to gather an image of what the transition into interstellar space is like.

In 2012, Voyager 1 observed a slightly higher-than-expected plasma density just outside the heliosphere, indicating that the plasma is being somewhat compressed.

In one of the papers, the researchers suggest that the interstellar medium near the heliopause is hotter than expected, with a temperature of around 30,000-50,000K (29,000-49,000C).

The heliosphere is a bubble-like region of space created by our Sun.

Voyager 2, with all of its functionality still intact has been more successful in this regard and has rewarded researchers with a slew of much anticipated information. Voyager 2 is only the second spacecraft to travel beyond the confines of the heliosphere.

The heliosphere is believed of like a cosmic weather front: a separate boundary where charged particles spreading outwards from the Sun at supersonic speed confront a cooler, interstellar wind blowing in from supernovae.

The Iowa scientists say the heliosheath has varied thickness, based on data showing Voyager 1 sailed 10 AU farther than its twin to reach the heliopause.

Another surprising finding was described in one of the papers: the magnetic field in the area just beyond the heliopause is mostly parallel to the magnetic field inside the heliosphere bubble. An accompanying standpoint implies that Voyager 2 is going to be the last spacecraft to cross this boundary for at least 25 many years.

"Voyager 2's interstellar arrival is a significant milestone because we are now able to look at our own star from outside in rather than inside out, and from not just one, but two perspectives", Rankin said.

Voyager-2 entered the ISM 119.7 astronomical units (AU), 11 billion miles from the Sun. "That's a characteristic of fluids, which oftentimes form very sharp boundaries", says Gurnett. An AU is the distance between Earth and the Sun. Despite the distinct boundary between environments, some particles from inside the "bubble" manage to escape into the interstellar space.

The electromagnetic junction simply exterior the heliosphere was considered a deeper transitional place of intermingling cosmic climate, however Voyager 2's plasma wave instrument - constructed by College of Iowa researchers - detected sharp jumps in plasma density, very like two completely different fluids coming into contact with each other."Think of a cold front that forms when a very cold air mass comes down to the US from Canada", stated Don Gurnett, professor of physics on the College of Iowa. The event has happened even since previous year, on November 5.

This occurs when the magnetic fields from two different objects briefly become connected through a tube-like magnetic structure.

"Both Voyager probes are exploring regions never before visited, so every day is a day of discovery", Stone said. Its 22.4-watt transmitter has a power equivalent to a fridge light, which is more than a billion billion times dimmer by the time it reaches Earth and is picked up by Nasa's largest antenna, a 70-metre dish.

"The space age was only 20 years old when they launched, so it was hard to expect anything to last for 40 years or longer", he added. They will likely not run into anything and could very well outlast planet Earth.



Other news