NASA's New Horizons
The New Horizons spacecraft is perhaps the most historic NASA mission since the Moon landing 46 years ago. The space probe will be getting up close and personal with Pluto this coming Tuesday, 14 July 2015. New Horizons onboard camera has the capability of resolving surface features that are 1.6km across. At this level of detail, New Horizons' camera has far surpassed even the Hubble Space Telescope's capabilities! Figure 1 shows the resolving power of the New Horizons' camera LORRI when it was under 8 million kilometres away from Pluto.
Figure 1: Photos of Pluto taken by the Hubble Space Telescope back in 2003 (left) and the New Horizons camera on July 7, 2015 (right).
“The Dwarf Planet, Pluto, is in many ways the kind of final outpost in the Solar System for close up exploration”, says Fred Watson, “We’ll probably see a landscape that is very different from anything we’ve even seen before in the Solar System.”
New Horizons has a suite of seven instruments with a broad range of capabilities including cameras, spectrographs and radio antennae. These instruments will gather data about the composition of Pluto’s atmosphere and the interaction with the Solar wind with this distant world. Perhaps most exciting for viewers back home, New Horizons will take detailed images of the surface, potentially revealing interesting geological features.
“This mission will allow us to learn about the history of the Solar System,” explains our Dr. Lucyna Kedziora-Chudczer.
“Until recently it was thought that water was delivered to Earth by comets. Recent research suggests that this isn’t the case as comets hold higher content of heavy water than measured in oceanic water. It is now believed that water was delivered to Earth from asteroids or Kuiper Belt Objects.”
“The New Horizons instruments will provide spectroscopic analysis of objects in the Kuiper belt zone, which will tell us what sort of watery substances are there and determine whether they hold water of similar composition as that in Earth’s oceans.”
In addition to gathering photos and spectral information, New Horizons has been measuring dust as it journeys through the Solar System.
“This is very interesting for those of us studying debris discs, which are dusty remnants of planet formation around stars. Understanding the distribution of dust in our own Solar System and comparing it other systems in the galaxy, will help us determine whether our dust distribution is typical of planetary systems.”
Once New Horizons completes its encounter with Pluto, its mission isn't over. Following that historic rendezvous, the probe will be redirected to a yet more distant body. The exact target has not been decided, but astronomers have pored over Hubble Space Telescope images and identified two candidates from which the selection will be made.
“The Planetary community will be poring over this data for the next five years,” says Fred. “It will allow us to understand Pluto and by extension the rest of these trans-Neptunian objects because it is probably very typical of what’s out there. I think there will be great excitement”.
Prof. Fred Watson is the Head of Environment and Lighting at the Australian Astronomical Observatory.
Dr. Lucyna Kedziora-Chudczer is part of the Planetary Atmospheres Group led by Prof. Jeremy Bailey.
Dr. Jonty Marshall is part of the Exoplanetary Science Group led by Prof. Chris Tinney.
Part 1 of the UNSW Physics mini-series can be viewed on our YouTube channel.
New Horizons probe was launched in 2006 back when Pluto was still known as a planet. Astronomers have now re-classified Pluto to a ‘Dwarf Planet’ in a controversial decision made by the delegates of the International Astronomical Union (IAU). Jonty Marshall talks us through the decision making process for defining a planet on our YouTube channel.