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space

Voyager 2 goes More than four decades after solar system. The planets in this alignment fall in a line, and How far will the Voyagers go?

therefore, it was possible for the spacecraft to visit all of them
The scientists at NASA estimate the fuel on the spacecraft to
last at least about another five years. After they exhaust all fuel,
beginning its epic journey, the
one after another, in the shortest possible time. The spacecraft
interstellar spacecraft crosses the elusive can use the gravity of each planet to swing itself to the next the vintage systems on the craft will turn off, but the craft will
planet, the manoeuvre is called the Gravitational Slingshot. The continue to travel in the interstellar space, but without us.
boundary that marks the edge of
NASA’s Ed Stone, while addressing conference on October 31
technique is so useful that it is used for every interplanetary
mission nowadays and saves a lot of fuel for the craft to travel
Sun’s realm, reports younis dar
the time and the power is dropping.”
great distances. said, the spacecraft was “cooling off, they are getting colder all
The unique alignment is said to occur once ever 176 years, He said that the Voyagers may not have enough power to
he humanity’s longest running space mission, Voy- observe the electrically charged hazes, called the plas - so unsurprisingly this was a rare moment for the scientists continue running scientific instruments after five years. NASA
ager 2, has exited the solar system, becoming only mas, which fills the boundary of the solar system and the at NASA. Taking advantage of this special alignment, the is equally stunned with the instruments onboard the Voyag-
the second spacecraft ever to achieve this tremen- interstellar space. Voyagers were sent on a journey towards ers which continue to work for more
dous feet. After a meticulous analysis of the data The probe as it interacted with the particles near the bound- the bigger planets, even Uranus and Nep- than 40 years now — Voyager 2 has five
T sent by the spacecraft’s instruments, the mission ary of our solar system sent back critical scientific data, help- tune. While Voyager 2 visited Jupiter, operational instruments, while Voyager
scientists at NASA have concluded Voyager 2 crossed the ing us more understand the nature of that region and Saturn, Uranus and Neptune, Voyager 1 1 has four. These instruments, according
outer edge of the heliosphere on November 5, the interstellar matter. The project scientist for was directed to explore Jupiter and Sat- to NASA, were designed to last just four
2018. Heliosphere is the outer bubble that Voyager Ed Stone described the impor- urn. The images of the planets sent back years.
surrounds our solar system, consist- tance of the data, saying, “The Voy- by these spacecraft have since been The Voyagers are powered by Radioi-
ing of particles and magnetic fields ager probes are showing us how extensively used for school textbooks Only two of humanity’s sotope Thermoelectric Generators (RTGs),
created by the sun. our Sun interacts with the stuff and scientific research. The twin space- which have served the these probes for
The sibling of the probe that fills most of the space craft went to the corners of our solar sys- spacecraft have left years in their humongous journey. These
Voyager 1 had already left between stars in the Milky tem which no one could even dream of the Solar System: generators run on the plutonium iso-
the solar system in 2012. Way galaxy. Without this going, lasting more than four decades tope, a rare element. However, the power
Launched in 1977 with new data from Voyager to the scientific community’s shock. The NASA’s Voyager 1 and from these generators has started to drop
just a gap of 15 days, the 2, we wouldn’t know spacecraft were only designed to operate Voyager 2. Voyager 1 and the scientists have had to shut down
two probes are now if what we were see- for just five years. several instruments in the last few dec-
more than 18 billion ing with Voyager 1 The Voyagers were originally sent for left the heliosphere ades to save power and let the probes
kilometres from was characteristic the exploration of Jupiter and Saturn. behind in 2012, while continue in their journey. The thrusters,
earth. The space- of the entire helio- The probes made startling discoveries which allow the probes to change direc-
craft are so far that sphere or specific on these planets, including thefinding Voyager 2 did the same tion, have reportedly started to degrade.
a command sent just to the location of active volcanoes on Jupiter’s moon Io on Nov. 5th, 2018. Now And luckily, the communication system is
from earth takes and time when it and the study of Saturn’s rings, besides a still working on both the probes, obvious-
16.7 hours to reach crossed.” plethora of other findings. Voyager 2 has been in ly, the most important ones. The cosmic
them, at the speed The Plasma Sci- As the spacecraft kept going on, NASA ray instrument onboard the Voyager 2
of light. For a com- ence Experiment decided to send Voyager 2 to explore Ura- interstellar space for was shut down this year to help the probe
parison, it takes (PLS)instrument nus and Neptune, the planets which have one year save power.
eight minutes for onboard the Voy- only been visited by the Voyager 2 probe. Running perpetually driven by the
the light to reach the ager 2 craft provided Now with over four decades of pathbreak- power of 1970s technology, the Voyag-
earth’s surface. Hur- a clear evidence to ing science, the probes were deployed ers run on extremely low power, es -
tling out of the solar the teams here on for a more challenging mission, called timated to be equivalent to today’s
system at 34,000 miles earth. Using the electri- the Voyager Interstellar Mission (VIM), fridge light. The duo is headed into
per hour, the spacecraft cal current of the plasma under which they were to explore the the interstellar space and the space -
have been travelling for to detect the speed, density, outermost edge of the Sun‘s domain. And craft may encounter the nearest star
more than 42 years now. In- temperature, pressure and beyond. in 40,000 years with such speed. The humanity will forever
credible! Isn’t it? flux of the solar wind,the PLS According to NASA, “the mission objective of the be grateful for the incredible scientific data they keep beam-
The Nature Astronomy jour- witnessed a steep decline in the Voyager Interstellar Mission (VIM) is to extend the NASA ing back to earth, enhancing our knowledge of the cosmos
nal this week described the find - speed of the solar wind particles on exploration of the solar system beyond the neighbourhood and igniting our imagination. The Voyagers are a testimony
ings as Voyager 2 left the boundary of November 5. The instrument, according to of the outer planets to the outer limits of the Sun‘s sphere of to the humanity’s insatiable quest for the unknown and all
the solar system. The instruments aboard NASA, observed no solar wind since then, which influence, and possibly beyond.” that we can achieve if we only endeavour. Any new probes
the spacecraft encountered a dramatic reduction in is a compelling evidence for the scientists to conclude the The information returned by the Voyagers of our outer aimed for interstellar travel, even if sent now, will take
the heliospheric particles, while the rate of cosmic rays in- probe had left the solar system. solar system has revolutionised our understanding and decades to reach where the Voyagers are, it’s why these mis-
creased significantly and have since been constant. This knowledge of our neighbourhood. The incredible craft which sions are special. Humanity, we can say, has established its pres-
observation led the scientists to conclude Voyager 2, like Journey of the Voyagers outlived their original lifetimes by more than eight times ence in the space among the stars.
its predecessor Voyager 1, had exited the solar system. It During the 1970s, scientists at NASA made an ingenious dis- have significantly contributed to our knowledge of the plan-
was for the first time that scientists were able to directly covery of a Once-in-a lifetime-alignment of the planets of our etary astronomy. letters@tehelka.com

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