The graphics on these pages note New Horizons' distance from Earth, the Sun and Pluto in AU, or Astronomical Units. One AU is the average distance between . I'll remind you of New Horizons' capabilities and simulate how Pluto will New Horizons' flyby of Pluto happens on July 14, at UT, but it . what date and distance LORRI will have comparable resolution on Pluto. Watch: Here's What New Horizons' Pluto Flyby Will Look Like. To view this video NASA's Simulator Puts All Eyes on Pluto. Share. Tweet.
New Horizons | NASA
Earth observations To prepare for the encounter, astronomers on Earth have been taking observations of MU69 as much as possible.
There are two main purposes for performing observations before New Horizons gets there. One is to improve the precision of predictions of its future path, which will make it easier to target New Horizons' observations.
The other is to learn what we can about the characteristics of the object -- its size, shape, and brightness. There are two main Earth-based observational efforts. One employs Hubble, the only telescope reliably able to observe MU69 from Earth. Other huge ground-based telescopes can, in principle, detect light from MU69, but only under absolutely perfect observing conditions.
Astronomer Marc Buie gave an update on the Hubble time that he's been allocated this year to support the mission: Buie told me in an email that "This work is actually a close collaborative effort with the Gaia mission and its science team. They are providing advance information from their upcoming DR2 data release 2 catalog that we use to precisely calibrate the HST data.
Without that support we would have much less precise knowledge of where MU69 will be at the time of encounter. I can't thank them enough for their contributions. The 24 frames in this animation were separated by 0. Observations like these will allow the team to constrain the size and position of the New Horizons mission's flyby target, improving the precision of their encounter planning.
Simulation of New Horizons' Pluto flyby - GIF on Imgur
This animation has been processed from the originally published version to reduce noise and align the star field. The other observational effort takes advantage of occultations of background stars by MU69 to measure its size and shape, as described for us in this article by Alejandro Soto last year. Like the Hubble work, precision of the occultation observations now depends on Gaia data.
Astronomers have deployed across the southern hemisphere twice, on June 3 and July 17,to watch MU69 pass behind a star. The June 3 occultation effort failed to detect any occultations; they learned later that they'd positioned themselves slightly too far to the north. The July 17 occultation produced the discovery that MU69 was irregular-shaped like Erosa contact binary more like Churyumov-Gerasimenkoor even maybe a close binary pair that just happened to be undergoing a mutual event like Pluto and Charon, only closer.
The colored lines mark the path of the star as seen from different telescopes on each day; the blank spaces on those lines indicate the few seconds when MU69 blocked the light from the star.
Scientists are using these observations to craft a picture of MU69 and any companion bodies. This diagram was drawn before the discovery of a few bugs in the astrometry software. Fixing those bugs and improvements in Hubble image reduction brought the main body of MU69 closer to its astrometry-predicted position and brought the single SOFIA "blip" closer to the main body.
The story is one of scientific serendipity. The higher parallax between observations revealed a couple of subtle bugs in Buie's software "one of them a case of me failing to read my own documentation, another one a sign error," he said.
Having fixed those bugs and also taking advantage of a new, cleaner data product that the Space Telescope Science Institute recently began to provide for Hubble WFC3 images, Buie reanalyzed last summer's occultation data.
The reanalysis very, very slightly shifted the positions of the three sets of observations with respect to each other, moving the July 10 and July 17 observations much closer to each other.
Consequently, the evidence for a possible moon at MU69 has evaporated. The SOFIA blip is now consistent with a bare nick of an occultation of the MU69 primary detected during the July 17 occultation, and all the occultation data lines up better with astrometric predictions. There is one more good MU69 occultation opportunity this year, on August 4, and the team should now be able to produce ridiculously specific predictions for where best on Earth to observe it.
New Horizons' timeline for The spacecraft wakes up June 4.
Watch a real time simulation of Tuesday's epic Pluto flyby with this app
For two days after, the spacecraft will be awake but keep thrusters quiet, as it broadcasts a signal to Earth for tracking purposes. Of course, the images will also be useful for science. Geologists will study them and compare them to Hubble observations to look for further surface changes on Pluto, and astrophysicists will use the navigational information to determine the masses of Pluto and Charon more precisely.
Late in the approach, as Pluto looms larger, the New Horizons team has done its best to command images at smooth intervals for the future creation of a movie of New Horizons' approach. While it's very exciting that New Horizons will begin imaging the Pluto system in January, it's important to keep your anticipation aligned with the reality of the photos. LORRI is a very high-resolution camera, but Pluto is not very big it's smaller than any of Jupiter's Galilean moons and will be, for the most part, far away from New Horizons.
Small and far away means few pixels and not a lot of surface detail, even as late as June of next year. It's not a perfect comparison, for a couple of reasons.
We know already that Pluto has a more contrasty surface than Io or Ganymede. Also, by June, every single image New Horizons takes of Pluto will be the best image ever taken of Pluto, so it's going to be thrilling no matter what. But there won't really be enough pixels for us to begin to say anything particularly insightful about what is happening on Pluto's surface until the beginning of July.
The text indicates the dates and distances of the Galilean moon photos, and indicates at what date and distance LORRI will have comparable resolution on Pluto scaling for the size of Pluto, which is smaller than Io or Ganymede. The second column is the same images, enlarged by a factor of 3 to make the individual pixels visible. In the third column, the images have been enlarged with interpolation. Another caution about planned optical navigation: This seems counterintuitive you might think you'd want higher resolution to spot the smaller moonsbut the tiny moons are so dim that it will be necessary to bin photons gathered from 16 LORRI pixels together to get enough signal to pick the tiny moons out of background noise.
All of these approach images see objects in the Pluto system at nearly full illumination, with a phase angle of 14 to 15 degrees. I wrote an earlier post in which I discussed the optical navigation campaign more thoroughly.
The images in that post were based on a preliminary observation table. The following table is up-to-date as of yesterday and lists all of the planned optical navigation images of Pluto, Charon, Nix, and Hydra, including when they will be taken, and from what distance and with what resolution. At the outset, the best resolution is about kilometers per pixel -- barely more than 2 pixels across Pluto which is roughly kilometers across.
It's going to be a long wait for those frame-filling photos that we all want! One final note about the op navs: But captured is not the same as returned to Earth; it may be several days before the data come down. New Horizons at Kennedy Space Center in The spacecraft is comparable in size and general shape to a grand piano and has been compared to a piano glued to a cocktail bar-sized satellite dish. New Horizons' body forms a triangle, almost 0.
The Pioneers have hexagonal bodies, whereas the VoyagersGalileo, and Cassini—Huygens have decagonalhollow bodies. A aluminium alloy tube forms the main structural column, between the launch vehicle adapter ring at the "rear," and the 2.
The titanium fuel tank is in this tube. The RTG attaches with a 4-sided titanium mount resembling a gray pyramid or stepstool. Titanium provides strength and thermal isolation. The structure is larger than strictly necessary, with empty space inside. The structure is designed to act as shieldingreducing electronics errors caused by radiation from the RTG. Also, the mass distribution required for a spinning spacecraft demands a wider triangle.
The interior structure is painted black to equalize temperature by radiative heat transfer. Overall, the spacecraft is thoroughly blanketed to retain heat. Unlike the Pioneers and Voyagers, the radio dish is also enclosed in blankets that extend to the body. While in the inner Solar System, the spacecraft must prevent overheating, hence electronic activity is limited, power is diverted to shunts with attached radiators, and louvers are opened to radiate excess heat.
While the spacecraft is cruising inactively in the cold outer Solar System, the louvers are closed, and the shunt regulator reroutes power to electric heaters. Propulsion and attitude control[ edit ] New Horizons has both spin-stabilized cruise and three-axis stabilized science modes controlled entirely with hydrazine monopropellant.
Helium is used as a pressurant, with an elastomeric diaphragm assisting expulsion. Significantly, had the backup option been taken, this would have meant less fuel for later Kuiper belt operations. There are 16 thrusters on New Horizons: Two star cameras are used to measure the spacecraft attitude. They are mounted on the face of the spacecraft and provide attitude information while in spin-stabilized or 3-axis mode. In between the time of star camera readings, spacecraft orientation is provided by dual redundant miniature inertial measurement units.