Pluto and New Horizons – explain what’s going on in this mission – Gazeta.pl

The first time we see up close so distant world

Pluto is too far away to see him like that. It is located 29 to 49 astronomical units from the Sun, which is 29-49 times farther than Earth. This can be represented in kilometers, but such numbers say little. But here it is: closest to the Sun comes over 4 436 820 000 km, most receding into 7 375 930 000 km.

All of this means so much that even the good telescope Pluto looks like another very dim star in the sky. Distinguishes him only his movement.

Here is the first image of Pluto taken in 1930 with the help of a powerful telescope:

​​ Fig. Wikipedia

Do not stun, right? Over the next decades, little has changed. This picture was taken 48 years after the previous – this bulge on the left hand photograph brought to light that Pluto is not, as previously thought, one large planet and a pretty little body, accompanied by a large moon, Charon.

Fig. US Naval Observatory

Hubble Space Telescope was only allowed to see something more. But let us not delude yourself – pictures still were quite miserable. Here are the best of them taken just five years ago.

​​ photo. NASA, ESA, M. Buie (Southwest Research Institute)

Now, however, the situation is changing. New Horizons to Pluto makes with great speed. How much? Suffice it to say that the distance from the Earth to the Moon probe defeated in 9 hours. Apollo astronauts took 3 days. It is thanks to this speed, beat the 4.8 billion kilometers took only 9.5 years.

At the end of April this year, New Horizons has exceeded the magic limit beyond which it made pictures of Pluto became better than those ever we saw. And literally every day to more and better photographs. Here are the most accurate of existing images captured from a distance of 1.6 million kilometers.

​​ Fig. NASA / Johns Hopkins University Applied Physics Laboratory / Southwest Research Institute

And on Tuesday evening will see probably even better photographs.

What is interesting about Pluto?

The mission of New Horizons is primarily a discovery in pure form. We do not plan to move to Pluto, we will (instead) to extract raw materials from it. We want to be is figure out about how the solar system was created. Pluto is one of the most distant objects in the Agreement but it is not known whether always been the case – one theory says that was formed much closer to the Sun and was thrown to the outskirts of the gravitational pull of planets bigger than yourself. Another version suggested that there was once a moon of Neptune, but pushed it out of orbit greater than he Triton.

​​ Fig. ASA, ESA, and G. Bacon (STScI)

Today, we believe that Pluto was built where it is or in the Kuiper Belt – a giant rubble stretching beyond the orbit of Neptune from about 30 to 50 units AU from the sun. Probably there are coming to us short-term comet like the famous Halley’s comet. Pluto is one of the largest (but not most) Kuiper Belt object and can tell us much about what has happened in this area over the past 4.6 billion years.

Why is Pluto no longer a planet?

Curiosity curiosity but do not kid yourself – a large impact on the costing $ five hundred million New Horizons mission come to fruition was the fact that she started flying to the only planet of the solar system, we were able to discover the Americans.

And then, just after seven months of flight, came the terrible news – the probe does not already flying toward the ninth planet of the solar system, and only in the direction of one of the many dwarf planets.

This is the effect the decision of the International Astronomical Union, which in August 2006 decided to degradation of Pluto. The reason was the adoption of a new definition of a planet. The planet in the solar system must be in orbit around the Sun, have sufficient mass to form a nearly spherical object and clean neighborhood of its orbit so that there was no other larger objects. And it is this last point had become fuss, because Pluto as a planet proponents claim that it was added just to exclude from their circle of respectable globe.

But the truth is that Pluto has long been lost its strong planetary position. Gradually, more and more objects were discovered that were very similar to him in size, shape and weight. We had to make a decision – either we are increasing cluster of planets, or put the border and exclude Pluto and similar him objects.

​​ Fig. EightTNOs.png: Lexicon

The case was settled the discovery of Eris in 2005 – also located in the Kuiper Belt rock sphere, which is even larger and heavier than Pluto which is almost as big as Pluto [This information is sent to Earth from the New Horizons already in the process when I wrote this text]. If he was a planet, the more it. That is why both have been included in the new category of dwarf planets, which is now still Ceres, Haumea and Makemake, and probably soon be joined by Sedna, Orcus and Quaoar in 2007 OR10.

Why can not we enter the orbit of Pluto?

We’d love to explore Pluto exactly, but it will have only a couple of minutes. Literally. The problem is that the probe New Horizons Pluto moves relative speed of about 14 km / s. To enter its orbit, it would have to slow down, and this zużyłoby a lot of fuel. To take them away, would have to be much heavier, and then would need more fuel to slow down. And so on.

​​ Rys.pluto.jhuapl.edu

Why it so so rozpędziliśmy? To reach Pluto in a generation of people. Slow and sedate flight allows for a quiet slowdown would take not less than 10 years, but a few dozen. During the flight, the New Horizons rozpędziliśmy it even more thanks to the so-called slingshot – a close fly past Jupiter broke up a probe so that as soon as you reach Pluto.

Fortunately, the entire mission from the beginning was prepared so that in a short time flight to gather as much information and send them to Earth.

How the New Horizons communicates with Earth?

Well – sent to Earth. It’s not that simple. Light, and therefore radio waves, flying from Pluto to Earth over 4.5 hours. So full cycle of communication – sending and receiving signals answers – takes 8 hours and 50 minutes. The signal sent by the New Horizons is from such a distance very very weak. To his collection uses the network of large, 70-meter Deep Space Network antennas located in California, Australia and Spain. This ensures that every probe, which is more than 30 000 km from Earth is always in range of a network.

The transmission speed from the vicinity of Pluto is about 1-2 kilobits per second. Photo having 1,024 pixels is sent to more than 40 minutes. Therefore, on-board New Horizons has three SSD, each of 8 gigabytes, which are used for data buffering. The message of what is collected during your trip around Pluto will take dozens of days of continuous transmission.

​​ Fig. NASA

In addition to the flight time will be interrupted – the probe will turn toward Pluto so as to explore it and thus lose contact with Earth temporarily away from the antenna. It was decided to follow this path after the experience with the mission of Voyager 2. There could antenna to rotate relative to the probe and the system broke down after a few years causing a lot of problems. New Horizons has more clumsy but rugged design.

What is New Horizons spacecraft?

At first glance – boredom. The probe as the probe. The dimensions of the hull: 0.7 mx 2.1 mx 2.7 m. Weight 478 kg. Made of aluminum, powered by a generator radioizotopowym containing 11 kg of radioactive plutonium dioxide plutonium 238. About this it was indeed scandal – when the probe competed so. environmentalists raised alarm that in case of failure of the rocket will destroy the Earth element. He does not tainted, even if 11 kg is very little. So platoon safely fly themselves toward Pluto (ha ha ha).

The more interesting you are doing, when we look at the scientific apparatus New Horizons. It’s eight scientific instruments. To quote Wikipedia are:

– Ultraviolet Imaging Spectrometer (Alice) – Ultraviolet Imaging Spectrometer studying the composition and structure of the atmosphere; observations in the wavelength range 465-1880 A

– Visible Imager and Imaging Spectrometer (Ralph) – an instrument consisting of two parts:

– multispectral Visible Imaging Camera (Ralph / MVIC) – multispectral camera in the visible and near-infrared and panchromatic perform colorful map of the surface of the examined bodies; observations in the wavelength range 400-975 nm

– Linear Etalon Imaging Spectral Array (Ralph / LEISA ) – mapping spectrometer performing near-infrared maps mineralogical and surface temperature measurements; observations in the wavelength range 1250-2500 nm

– Radio Science Experiment (REX) – the measurement of pressure and temperature of the atmosphere and ionosphere density, measurements of weight and size of the bodies examined

– Long Range Reconnaissance Imager (Lorrie) – the high-resolution panchromatic camera; observations in the wavelength range 350-850 nm

– Solar Wind at Pluto (SWAP) – the solar wind particle detector; perform measurements of the speed and density of the solar wind and the pace escape Pluto’s atmosphere

– Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI) – the charged particle spectrometer

– Venetia Burney Student Dust Counter (VB-SDC) – particulate matter sensor

The latter instrument was named after the Venetia Burney, who in 1930 age 11 invented the name “Pluto” for the new the planet.

​​ Fig. NASA

The instruments are explored, among others, composition and variability of Pluto’s atmosphere, determine if nearby there are many fine particles but mainly thoroughly examine the dwarf planet’s surface and make her maps as accurate as possible. We will examine too Charon, Pluto’s largest moon. We will be looking for a possible magnetic field of both bodies, check to see if Pluto does not have a chance Rings.

​​ Fig. NASA

The most interesting, however, are the “extras” that have been loaded on board. Then 30 grams of ashes of Pluto discoverer, Clyde Tombaugh, 434 738 names of people stored on a CD (could be reported for free), flag US, a quarter of Florida (officially serves to balance the probe) and a postage stamp of 1991 with Pluto drawing and the words “Pluto unexplored.”

What’s on Pluto?

Flight New Horizons Pluto wheel is not the end of the mission. The probe can operate at least until the 2020-2022 year. It will continue flying through the Kuiper Belt, perhaps you will be somewhat changed its flight path in order to flew close to other larger objects. However, the room for maneuver is very limited supplies of fuel carried.

Upon completion of this phase of the mission, New Horizons will fly in the direction of the constellation Sagittarius. Leave the solar system about 2,047 years. One can not, however, pick up the probes Voyager 1 and 2 of Title farthest objects that are man-made – it goes too slow.

What have we learned about Pluto New Horizons mission?

That the area is varied and has an interesting geological structure.

​​ Fig. NASA

That its largest moon, Charon, also has a rich geology

​​ Fig. NASA

That Pluto is slightly larger than we expected, bigger than Eris, and has 2,370 +/- 20 km in diameter. Calculating the mass did not change, which means that Pluto has a slightly lower density than expected. And that means that a proportional increase in the amount of ice to rock in its interior. This also means that the atmosphere is a little thinner than expected.

That Pluto has polar caps formed from methane and nitrogen ice.