The United States Space Force has unveiled a black and silver logo, following an earlier design released by president Donald Trump that proved controversial.

Revealed 22 July, the logo comprises a delta symbol with a silver border intended to represent defence against "adversaries and threats emanating from the space domain". It encloses a black centre indicative of deep space.

Four grey bevelled elements break up the black centre to symbolise the four armed forces the Air Force, Army, Navy and Marine Corps, which will support the space mission. They encase the star Polaris, also known as the North Star.

Trump released a logo design in January 2020 on Twitter based on the delta symbol, just one month after the Space Force military branch was created. This design composed a circular seal around an arrow-shaped spaceship and a white swoosh with a universe backdrop.

The design was met with criticism on social from design figures including Pentagram partner Michael Bierut and UK graphic-design studio MHD. Others likened the design to the Star Fleet logo from the cult TV show Star Trek.

At the time, Space Force officials defended the logo in a statement posted on Facebook, highlighting the historic use of the delta symbol in the US armed forces.

"The delta symbol, the central design element in the seal, was first used as early as 1942 by the US Army Air Forces; and was used in early Air Force space organization emblems dating back to 1961," it said.

"Since then, the delta symbol has been a prominent feature in military space community emblems."

In addition to the new logo, the US Space Force has also unveiled its motto as Sempa Supra, which translates from Latin as Always Above.  "The logo and motto honor the heritage and history of the US Space Force," it said.

The US Space Force was established in December 2019 as part of a $738 billion (£564 billion) military spending bill passed by the US Congress. It is the first new US military branch to be introduced since the launch of the Air Force in 1947, and now forms part of the existing Air Force department.

The objective of the new force is to protect US and allied interests, including assets such as satellites, in space.