A Japanese logging company Sumitomo Forestry and Kyoto University have joined forces to develop what they hope will be the world’s first satellites made out of wood by 2023, says a BBC report. The partners announced their intentions on Wednesday, saying the aim was basic research and proof of concept. They have agreed to conduct research on tree growth and the use of wood materials in space. They hope to promote technology for using wood in extreme environments on Earth.
Space junk is becoming an increasing problem as more satellites are launched into the atmosphere. Wooden satellites would burn up without releasing harmful substances into the atmosphere or raining debris on the ground when they plunge back to Earth. Further, wood does not block electromagnetic waves or the Earth’s magnetic field. This enables devices such as antennas and attitude control mechanisms to be placed inside a wooden satellite, allowing for simpler structures.
Through March 2024, the partners also will study building wooden structures in space environments. Sumitomo Forestry aims to develop wooden construction materials highly resistant to the elements as well as temperature changes and sunlight.
Space debris or space junk include derelict spacecraft—non-functional spacecraft and abandoned launch vehicle stages—mission-related debris, and particularly numerous in Earth orbit, fragmentation debris from the breakup of derelict rocket bodies and spacecraft. In addition to derelict human-built objects left in orbit, other examples of space debris include fragments from their disintegration, erosion and collisions, or even paint flecks, solidified liquids expelled from spacecraft, and unburned particles from solid rocket motors. Space debris represents a risk to spacecraft.
In October 2019, the US Space Surveillance Network reported nearly 20,000 artificial objects in orbit above the Earth, including 2,218 operational satellites.
Although most debris burns up in the atmosphere, larger debris objects can reach the ground and harm the earth. According to NASA, an average of one cataloged piece of debris has fallen back to Earth each day for the past 50 years. Despite their size, there has been no significant property damage from the debris but thre have been notable examples of space junk falling to Earth and impacting human lives.
In 1969, five sailors on a Japanese ship were injured by space debris. In 1997, an Oklahoma woman, Lottie Williams, was injured when she was hit in the shoulder by a piece of blackened, woven metallic material confirmed as part of the propellant tank of a Delta II rocket which launched a U.S. Air Force satellite the year before.
In 2001, a Star 48 Payload Assist Module (PAM-D) rocket upper stage re-entered the atmosphere, crashing in the Saudi Arabian desert. It was identified as the upper-stage rocket for NAVSTAR 32, a GPS satellite launched in 1993. In 2003, in the Columbia spacecraft disaster, large parts of the spacecraft reached the ground and entire equipment systems remained intact. More than 83,000 pieces, along with the remains of the six astronauts, were recovered in an area from three to 10 miles around Hemphill in Sabine County, Texas.
In 2007, airborne debris from a Russian spy satellite was seen by the pilot of a LAN Airlines Airbus A340 carrying 270 passengers whilst flying over the Pacific Ocean between Santiago and Auckland. The debris was reported within 9.3 kilometres (5 nmi) of the aircraft.
Shobhil Shrivastava 
Satish Chogule