According to hazard-search images taken by NASA's New Horizons spacecraft and analyzed by its earthbound team, it appears that the path toward the planet is clear.
Taken between May 11 and 12, the first set of images shows observations made 47 million miles away, using the New Horizons' Long Range Reconnaissance Imager. Of these observations, 144 pictures were taken by LORRI at 10-second exposures each, all designed to facilitate a high-sensitivity search for faint dust sheets, rings or satellites in Pluto's system.
The spacecraft's mission team carefully studied all indications of debris or dust that could pose a threat to New Horizons — because a particle as small as a grain of rice could produce a catastrophic outcome.
The New Horizons photographs were sent to Earth May 12 through 15 and were processed and analyzed by May 18. According to the images, the spacecraft detected Pluto and all of the planet's five known moons — but no new moons, rings or other hazards were revealed.
Led by John Spencer from the Southwest Research Institute, the hazard detection team determined that a small satellite with about 50 percent of the brightness of Styx – Pluto's faintest moon – can be detected at the current range.
What does this mean? If there are any undiscovered moons out there beyond the orbit of Charon – Pluto's closest and largest moon – they will likely be smaller than 3 to 10 miles in diameter. Additionally, if there are any undiscovered rings around Pluto outside of Charon's orbit, they will be very narrow or faint, sized less than a thousand miles wide or reflecting less than one 5-millionth of incoming sunlight.
The next set of hazard-search images will be captured between May 29 and 30 and is expected to show twice the sensitivity of the most recent series. The New Horizons team expects that all analysis will be accomplished and reported by June 12. If the need arises, New Horizons may be diverted to one of the three alternate routes prepared for the spacecraft. The team will only have until July 4 to make the changes.
New Horizons is currently almost 2.95 billion miles away from Earth. It is speeding towards Pluto at a speed just shy of 750,000 miles per day. All systems are operating normally, which increases the chances of success for the mission.
New Horizons is set to fly through Pluto's system on July 14.
