Probe peels back mysteries of the universe

Remote: Our solar system, the heliosphere, and the Voyagers — tiny specks in space.

Is remote exploration a form of escapism? NASA has sent spacecraft 12 billion miles from Earth. One scientist says it is like exploring an elephant with a microscope. Why do we bother?

A matter of hours ago, almost precisely a year since it crossed into interstellar space, the probe has sent back a message.

Beyond Jupiter, beyond Neptune, beyond the furthest reaches of the Sun itself, a NASA probe wanders in interstellar darkness.

After completing a 41-year journey and the first ever flybys of Uranus and Neptune, Voyager 2 left our solar system in November 2018. Scientists are amazed that the craft has made it so far.

Our Sun roars through space at 450,000 miles per hour, spiralling around the centre of the Milky Way. As it travels, the star’s fiery, volatile surface throws off bursts of solar wind, which form a bubble called the heliosphere.

Scientists have been hoping that these two pin-points could tell us more about the shape of the heliosphere. Some predict that it is round, while others think it is more like a comet, leaving a long tail of solar matter.

The new data from Voyager 2 suggests that the bubble is indeed spherical, but not everyone convinced that we’ve learned much at all.

“It’s kind of like looking at an elephant with a microscope,” said research scientist Bill Kurth. “You have no idea what’s going on between [the two points].”

Is he right?

Into the void

Of course, say some. These two points are less than a grain of sand in the vast dunes of the heliosphere. We still have no idea how far it stretches out around us, or what bizarre, contrasting conditions may be found in its far reaches. You only have to look at the conflicting Voyager readings to see that.

So unfair! Or so say the fans of space science. Forty-two years after they were launched, the spacecraft are still going strong and exploring the outer reaches of our cosmic neighbourhood. The two spacecraft are now more than 10 billion miles from Earth. What could be more valuable or exciting than that?

You Decide

  1. Why are we so fascinated by the stars?


  1. Draw what you imagine the opposite edge of the Universe might look like.

Some People Say...

“For small creatures such as we the vastness is bearable only through love.”

Carl Sagan (1934-1996), US astronomer and cosmologist

What do you think?

Q & A

What do we know?
Voyager 2 was launched by NASA in 1977. After taking the only ever close-up images of Uranus and Neptune, it exited our solar system in November 2018. After a year of waiting, the probe has sent back its first message about its passage.
What do we not know?
Exactly how long we will be able to stay in touch with Voyagers 1 and 2. They are projected to drop below critical energy levels in the mid-2020s.

Word Watch

Between star systems. “Stellar” refers to stars.
A space probe is a robotic spacecraft that does not orbit Earth, but goes further into outer space.
The only man-made object. Voyager 1 took a different route.
Evaporates quickly.
Solar wind
Charged particles that are released from the surface of the Sun. If they hit earth directly, these winds can cause disruption to electronics and power lines.
A huge bubble encompassing our solar system, which is full of solar weather.
An icy, small solar system body.
Shaped like a sphere.
A hill of loose sand made by wind blowing or water.

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