An easy way to see parallax is to place one finger at arm’s length and watch it jump back and forth when you view it successively with each eye.
Similarly, as Earth makes it way around the Sun, the stars shift their positions.
But because even the nearest stars are hundreds of thousands of times farther away than the diameter of Earth’s orbit, the parallax shifts are tiny, and can only be measured with precise instrumentation.
In this case, scientists compared images of the ‘alien sky’ snapped by the New Horizons spacecraft to pictures taken of the same stars – Proxima Centauri and Wolf 359 – that day, from telescopes on Earth.
It helped them map the “largest parallax baseline” ever made – over seven billion kilometres.
And the spacecraft isn’t finished yet.
The New Horizons spacecraft is truly a mission of firsts, and this demonstration of stellar parallax is no different" said Kenneth Hansen, New Horizons program scientist at NASA Headquarters in Washington.
The New Horizons spacecraft continues to speed away from Earth toward interstellar space and is continuing to return exciting new data for planetary science.
Next up: that whole infinity thing we were talking about.