WHERE NEXT? NASA names its six dream destinations
NASA has supported four missions so far under the New Frontiers programme, and now the space agency has identified six potential targets on five different Solar System bodies for the next New Frontiers mission. And the nominations are...
THE MOON Crater could reveal bombardment
DESTINATION: The Moon’s surface – or a giant crater.
MISSION 1: Space probe to take samples from the South Pole-Aitken Basin crater.
MISSION 2: Seismic measuring stations analyse the Moon’s interior.
NASA has nominated two possible lunar missions for New Frontiers 5. One will go to the South Pole-Aitken Basin crater, which was created by an impact 4.2+ billion years ago. Analyses of the crater could provide new insights into the Late Heavy Bombardment period, when asteroids and comets rained down on the inner Solar System planets, including Earth. The second possible mission to the Moon is to make seismic measurements of earthquakes, and thereby gather a more detailed picture of our Moon’s internal structure.
THE COMET Comet may include the building blocks of life
DESTINATION: An unspecified comet.
MISSION: Probe to collect a sample from the surface.
Comets can have diameters ranging from a few hundred metres to more than 10km. They consists of loose collections of ice, dust and small rocks and are hence often referred to as ‘dirty snowballs’. The primary purpose of the mission would be to examine the comet material for complex organic molecules. Analyses of meteorites found on Earth suggest that some comets and asteroids include amino acids, the building blocks of life, and perhaps even some of the bases that make up DNA and RNA. This has fuelled theories that the building blocks of life perhaps did not originate on Earth, but may have come from elsewhere.
THE ICY MOON In search of life under the ice
DESTINATION: Saturn’s ice-covered moon of Enceladus.
MISSION: Space probe to fly close to Enceladus or perhaps even orbit the moon.
Enceladus includes a sea of liquid salt water beneath its frozen surface, and through cracks in the ice, geysers hundreds of km long shoot out into space. By collecting material from the geysers, the probe can investigate what substances the water contains. Previous measurements made by the Cassini probe have indicated that all the elements necessary for life are present, but actual signs of life have not yet been found. So the mission's main goal is to find biosignatures, i.e. organic molecules that could be evidence that Enceladus harbours life.
THE GAS PLANET Multi-probe mission to Saturn
DESTINATION: Saturn’s atmosphere.
MISSION: Probes could be sent on missions through the gas giant’s atmosphere. They would not return...
Saturn consists almost entirely of hydrogen and helium, but the atmosphere also includes other elements, and a series of small probes could capture those. On no-return missions through the atmosphere, the probes could use mass spectrometers to measure the distribution of different isotopes of hydrogen, carbon and oxygen. Other instruments could provide data on temperature and pressure in the atmosphere's different layers. Equipped with parachutes, the probes might reach 250km into the atmosphere and transmit data for up to an hour before being destroyed by the pressure.
THE VOLCANIC MOON Volcanic eruptions shaped moon
DESTINATION: Jupiter's moon Io.
MISSION: Space probe to fly close to Io or perhaps even orbit the moon.
Io is Jupiter's third largest moon and the Solar System body with the most extreme volcanic activity. A mission would focus on the causes and consequences of this geological activity. The probe could collect data showing Io's tectonic processes and how they are caused by gravitational forces from Jupiter and its other large moons. In addition, the probe might map out Io's surface and investigate how much of the moon's mantle is liquid. Finally, the probe could measure whether Io produces its own magnetic field and hence whether it has a liquid iron core.