Navigation system doubts delay Genesis mission

2019-03-06 09:05:24

By Catherine Zandonella The launch of a spacecraft designed to collect samples of the solar wind, the stream of electrically charged particles flowing from the Sun, has been postponed. Originally scheduled for Monday, lift-off was delayed after a possible fault was identified with the spacecraft’s navigation system. A similar device failed during space environment testing on the ground and engineers are hurrying to determine whether the same fault could occur aboard the Genesis mission. If the device is judged safe, however, the mission could be rescheduled for take-off at 1230 EDT on Tuesday, weather permitting. The forecast gives a 70 percent chance of suitable weather conditions at the launch site at Cape Canaveral Air Force Station in Florida. Planetary scientists are keen to measure the atoms, ions and isotopes that make up solar wind. “By sending this craft into space we hope to discover the starting material of the solar system,” says Donald Burnett of the California Institute of Technology in Pasadena and leader of the Genesis project. To protect the precious solar samples upon return to Earth, NASA plans a dramatic helicopter rescue. The elements wafting from the Sun date back more than five billion years, when a cloud of gas and dust called a solar nebula collapsed and formed the nascent star we now call the Sun. The Sun’s outer layer in effect contains a fossil record of its own creation, and the creation of the planets. By bringing the samples back to Earth, scientists can make detailed measurements of the relative amounts of these early elements and their isotopes. One element scientists are especially curious about is oxygen, which exists in three different isotopes in different parts of the solar system. Researchers hope to find out whether these isotopes existed in the same ratios in the solar nebula, which they believe will lead to an understanding of how the gas and dust of the early solar system coalesced into planets. After launch, the craft will head for a prime sun-bathing spot in orbit around the LaGrange 1 point, an area of space between the Sun and Earth where gravitational forces on the craft are balanced. Genesis looks something like a flying watchband with its solar panels extended. A large canister on the “face” of the watch contains collection surfaces. The craft will collect samples from three types of solar wind, “fast”, “slow”, and the massive expulsion of plasmas known as coronal mass ejections. Upon the craft’s return to the Earth in 2004,