What You Need to Know About the Pluto Flyby
Vasudevan Mukunth
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In under seven hours, the NASA New Horizons space probe will flyby Pluto at 49,900 km per hour, from a distance of 12,500 km. It’s what the probe set out to do when it was launched in January 2006. The flyby will allow it to capture high-resolution images of the dwarf planet’s surface and atmosphere as well as take a look at its biggest moon, Charon. For much of the rest of the day, it will not be communicating with mission control as it conducts observation. The probe’s Long-Range Reconnaissance Imager (LORRI) has already been sending better and better pictures of Pluto as it gets closer. During closest approach, Pluto will occupy the entire field of view of LORRI to reveal the surface in glorious detail.
Fourteen minutes into the Pluto flyby, New Horizons will make its closest approach to Charon, which is about 24,000 km away. Next: 47 minutes and 28 seconds after the Charon flyby, the probe will find itself in Pluto's shadow where its high-gain antennae will make observations of how the dwarf planet's atmosphere affects sunlight and radio signals from Earth as they pass through it. Then, 1 minute and 2 seconds after that, New Horizons will again be in sunlight. Finally, 1 hour and 25 minutes later, it will be in Charon's shadow to look for its atmosphere.
That New Horizons survived the flyby will be known when, on early Wednesday morning (IST), it starts to send communication signals Earthward again. The timings of various events announced by NASA will have to be adjusted against the fact that New Horizons is 4.5 light-hours away from Earth. NASA has called for a press conference to release the first close-up images at 0030 hrs on July 16 (IST). The entire data snapped by the probe during the flyby will be downloaded over a longer period of time. According to Emily Lakdawalla,
Following closest approach, on Wednesday and Thursday, July 15 and 16, there will be a series of “First Look” downlinks containing a sampling of key science data. Another batch of data will arrive in the “Early High Priority” downlinks over the subsequent weekend, July 17-20. Then there will be a hiatus of 8 weeks before New Horizons turns to systematically downlinking all its data. Almost all image data returned during the week around closest approach will be lossily compressed — they will show JPEG compression artifacts. Only the optical navigation images are losslessly compressed. [All dates/times in EDT]
Downloading the entire science dataset including losslessly compressed observations will take until around November 2016 to complete. Until then, the best will always be yet to come. As always, all communications will be via the Deep Space Network - whose Goldstone base is currently all ears for the probe.
Incidentally, the ashes of the astronomer Clyde Tombaugh, who discovered Pluto in 1930, are onboard New Horizons.
What do we know about Pluto?
Among the last images taken by LORRI before the flyby revealed a strange geology on Pluto. Scientists noted dark and bright polygonal patches (in the shape of a whale and a
This article went live on July fourteenth, two thousand fifteen, at twenty-one minutes past ten in the morning.The Wire is now on WhatsApp. Follow our channel for sharp analysis and opinions on the latest developments.