Voyager 1 is to exiting our solar system and becoming the first man-made object to enter interplanetary space, it would be an excellent coincidence if it finally made the transition today, on the 35th anniversary of its launch into space.Given how close
Right now, Voyager 1 is over 18.2 billion kilometres away from the Sun, flying at a speed of over 62,000 kilometres per hour, and is in a region of our solar system known as the heliosheath. On July 28th of this year, scientists at NASA received some exciting news from the probe, as it reported two distinct changes in its environment. Early on the 28th the probe's cosmic ray instrument detected a 5% increase in the number of high-energy cosmic particles that originate from outside our solar system, and then later in the day the number of lower-energy particles that originate from inside our solar system dropped by half. These changes were identified as two of the three expected changes that Voyager would see as it passed out of our solar system and entered interstellar space. The third and last requirement that scientists are looking for now is a change in the direction of the magnetic field.
During its primary mission to fly by the planets Jupiter and Saturn, Voyager 1 returned amazing images of the two planets, including their moons and rings, and even now has lived far beyond expectations, but it had something of a rocky start.
Back in the '60s, NASA came up with a bold plan called The Grand Tour, that involved four unmanned probes — two to be launched in 1976 and 1977, to fly by Jupiter, Saturn and Pluto, and two to be launched in 1979 to fly by Jupiter, Uranus and Neptune — but budget cuts in the early '70s caused NASA to scrap the plan. However, when plans for the last two missions in the ongoing Mariner program were scaled back due to further budget cuts, and the vehicle designs changed significantly due to technological advancements, NASA decided to change the missions and incorporated aspects of the old Grand Tour plan. Thus, Mariner 11 and 12 were renamed as Voyager 1 and 2 and launched 16 days apart in 1977.
The probes are not operating at 100% these days, due to limitations on how much electricity they have available from their power cells, but they are both still transmitting signals back to Earth, providing information on their location and speed, and the environment they are passing through. Before it shut down its cameras, Voyager 1 even sent back a 'Family Portrait' of the solar system, capturing images of the Sun, Earth, Venus, Jupiter, Saturn, Uranus and Neptune.
There's at least one Canadian connection that I know of on the Voyager missions. Dr. Jack McConnell, a professor of atmospheric science at York University, in Toronto, studies planetary atmospheres and worked on the Voyager Ultraviolet Spectrometer team. The UVS collected atmospheric data as Voyager 1 flew by Jupiter and Saturn, giving Dr. McConnell and his colleagues a glimpse at the dynamics and chemical interactions in the upper atmospheres of these planetary giants.
I don't hold too much hope that Voyager 1 will enter interstellar space today, but from all indications, we shouldn't have too long to wait. After that, it should continue to transmit data until finally losing all power sometime in 2025 and, unless it encounters something (or someone) unexpected, in roughly 40,000 years it will pass within 1.5 lightyears of Gliese 445, a red dwarf star in the constellation Camelopardalis.