Aerojet, a GenCorp company which provides spacecraft thrusters, is upbeat as spacecraft Voyager 1 has reached a point at the edge of our solar system where outward motion of solar wind is absent.

Now approximately 10.8 billion miles from the sun, Voyager 1's passage through the heliosheath, the turbulent outer shell of the sun's sphere of influence, and the spacecraft's expected departure from the solar system, said NASA in a statement last week.

It marks a major milestone as it will become mankind's first interstellar probe, said the company in a statement. In about 40,000 years, Voyager 1 will drift within 1.6 light years (9.3 trillion miles) of AC+79 3888, a star in the constellation of Camelopardalis. Command signals to the thrusters now take 16 hours to reach the spacecraft.

Voyager 1 and Voyager 2 were launched in 1977, and are the oldest operational spacecraft. At launch, each spacecraft carried two propulsion systems, a Delta-V system, including four 100-pound and four 5-pound monopropellant hydrazine thrusters made by Aerojet, and an attitude control system including 16 0.2-pound mono-propellant hydrazine thrusters.

The Delta-V systems have collapsed but the attitude control systems still remain operational. The 100-pound thrusters are the original version of the thrusters intended for Orion's crew module and the 0.2-pound thrusters are the ancestors of those in use for the Global Positioning System Block IIR, and are similar to those newly in service for GPS Block IIF, the company said.

Voyager has transformed our understanding of the solar system, said Aerojet Program Manager Jon Schierberl. Aerojet is proud to have been a part of the mission every step of the way. Schierberl is one of a handful of people at Aerojet who has worked programs (including Voyager) that have explored or will explore every planet in the solar system.

GenCorp is a manufacturer of aerospace and defense products and systems with a real estate segment that includes activities related to the entitlement, sale, and leasing of the company's excess real estate assets.