CURIOUSITY CORNER

QUESTIONS AND ANSWERS ON SOLAR SYSTEM

(Some interesting questions with answers on the above topic are displayed below. If you want answers to some more questions on this topic that have not been covered so far, you may write your questions in the Comment Box given below. We would certainly respond to your questions.)

    1. What are the lines seen on the planet Jupiter?

 Ans:  Jupiter's stripes or 'bands' which are seen with a telescope are caused by differences in the chemical composition and temperature of the atmospheric gas. The light-colored bands are called 'zones' and show regions where the gas is rising. The dark-coloured bands are called 'belts' and show the regions where gas is sinking.

    2. What would have been happened had our Earth had a Ring like Saturn instead of the Moon?

 Ans: First, it would form a spectacular sight for a viewer to see a huge wall erected in the sky. Secondly, because the  Ring consists of myriads of rocks and ice crystals (just like Saturn’s Ring) freely moving in space, it would pose a potential risk for rockets and planes flying in the sky. Better that we did not have a Ring like Saturn!

3.   How can we live on Mars? I have read that many rocket companies are trying to get there.

 Ans: As you know, Mars does not have any Ozone layer to protect life from the hazardous UV radiations from the Sun. Mars atmosphere is also very thin predominantly made of Carbon dioxide gas. There is no water on Mars although it is believed that its polar ice caps store a  lot of water in ice form. Mars is also a very cold place with night-time temperature dropping down to -73⁰ C. Given the inhospitable conditions of Mars, we cannot live ordinarily in the open. We have to live inside fibre domes built with materials brought from the Earth. Initially, we have to bring a lot of living stuff from the Earth like air, water, food, etc with repeated space flights. Gradually plants can be made to grow inside our dome house. We should also learn how to produce electricity inside our Martian homes to meet our energy needs in our day-to-day life.  With a bit of experience, we can grow a lot of vegetables and fruits like apple, orange, spinach, etc to serve our dishes. As we would be used to the Martian conditions, we would become less and less dependant on Earth relying mostly on Martian resources.

 4. Why Pluto was not regarded as a planet?

 Answer: Pluto is no longer regarded as a planet as it did not fit the revised definition of a planet given by the astronomers of the International Astronomy Union ( IAU) in their meet in 2006. Unlike a planet, Pluto is smaller in size and does not have a clear orbit in space. It is considered a Dwarf planet now.

 5.     Why Eris is not regarded as a planet?

 Ans: Eris is the most massive and second-largest known dwarf planet in the Solar System. It was discovered in January 2005 by a Palomar observatory-based team led byMike Brown named after the Greco-Roman goddess of strife and discord. Eris is the ninth most massive known object orbiting the Sun, and the sixteenth-most massive overall in the Solar System. Eris has been measured at nearly  2,326 km in diameter; its mass is 0.28% that of the Earth and 27% greater than that of Pluto, although Pluto is slightly larger by volume.  Eris may complete one rotation every 25.9 hours, making the length of its day close to ours. Because Eris appeared to be larger than Pluto, NASA initially described it as the Solar System's tenth planet. This, along with the prospect of other objects of similar size being discovered in the future, motivated the  (IAU) to define the term 'planet' for the first time. Under the IAU definition approved on August 24, 2006, Eris is a "dwarf planet," along with objects such as Pluto, Ceres, Haumea and Makemake. thereby reducing the number of known planets in the Solar System to eight, the same as before Pluto's discovery in 1930. Like Pluto, it does not have enough mass to be deemed as a planet.

6. Why doe Mars have rusted iron? Won’t this affect the metal which will be used to build domes?  Won’t it also affect the humans visiting the planet because it causes diseases like Tetanus?

 Ans: The rocks and soil on the surface of Mars (called Regolith) contain a dust that is primarily made up of iron (in addition to small amounts of other elements, including chlorine). Winds eroded these surface rocks and soil, and ancient volcanoes blew out the iron, spreading it all over the planet. When this happened, the iron within the dust reacted with oxygen, producing a red rust color. So, Mars is red because it has a layer of rusty dust covering its entire surface! However, the planet has little amount of Oxygen in its atmosphere ( 0.16%) at present to cause substantial oxidation to any iron-made materials on its surface like the materials to be used in our future Martian homes. Yes; the Martian soil, indeed, is toxic due to the presence of an unusually large amount of Iron oxide in it.

7. ମଙ୍ଗଳ ଗ୍ରହ ର ସୂର୍ଯ୍ୟ ଙ୍କ ଚତଃପାଶ୍ୱର୍ରେ ପରିକ୍ରମଣ କାଳ ଆମ ପୃଥିବୀର ପରିକ୍ରମଣ କାଳର ୨ ଗୁଣ I ତେଣୁ ଆମ ପୃଥିବୀରେ ୨ ବର୍ଷ ମଙ୍ଗଳ ଗ୍ରହ ର ୧ ବର୍ଷ ସହ ସମାନ I ମଙ୍ଗଳ ଗ୍ରହରେ ଉପରିପାର୍ଶ୍ଵ ରେ ଜଳ ବରଫ ଅବସ୍ଥା ରେ ଅଛି ସେହି ବରଫ ରେ ଅନ୍ୟାନ୍ୟ ଗ୍ୟାସ୍ ଦ୍ରବୀଭୂତ ହୋଇ ଅଛି ଓ ତାହାକୁ ଆମେ ଯଦି ତରଲାଇବା ତେବେ ତାହା ଆମକୁ ଶୁଦ୍ଧ ଜଳ ପ୍ରଦାନ କରି ପାରିବ ନାହିଁ I ଏହା କ’ଣ ଠିକ୍ କି?

ଉତ୍ତର : ମଙ୍ଗଳର ମେରୁରେ ମୂଖ୍ଯତଃ କଠିନ ଅଙ୍ଗାରକାମ୍ଳ ଗ୍ୟାସ୍ ର ବରଫ ରହିଛି I ଏଭଳି ଅଙ୍ଗାରକାମ୍ଳ ଗ୍ୟାସ୍ କୁ ଶୁଷ୍କ ବରଫ ( Dry Ice)  କହନ୍ତି I ବସନ୍ତ ରୁତୁ ସମୟରେ ସୂର୍ଯ୍ୟ ମଙ୍ଗଳର ମେରୁ ଉପରେ ଲମ୍ବ କିରଣ ପ୍ରଦାନ  କରୁଥିବାରୁ ଅଙ୍ଗାରକାମ୍ଳର ଏହି ଶୁଷ୍କ ବରଫ ତରଳି ଯାଇ ଗ୍ୟାସ୍ ଆକାରରେ ବାୟୁମଣ୍ଡଳକୁ ନିର୍ଗତ ହୁଏ I ସୁତରାଂ ମଙ୍ଗଳର ମେରୁରେ ଥିବା ଜଳକୁ ଆମେ ସିଧା ପିଇ ପାରିବା ନାହିଁ I 

8. Why the planets closer to the Sun are rocky and planets away from the Sun are gaseous?

Ans: The planets in our Solar System are believed to have formed from the same spinning disc of dust that formed the Sun. This disc, called the solar nebula, was composed mainly of hydrogen and helium gases, but also had other elements in smaller proportions. The nebula had a certain amount of angular momentum orbiting the baby Sun. Particles in the spinning disc began to clump together as gravity attracted them to each other. Over a few million years, many of these chunks had merged together and there were about 10⁹ objects called planetesimals, with diameters of about 1000 m. Over time, the planetesimals continued to collide and join together, attracted by gravity. These larger objects, about the size and mass of our Moon, are called protoplanets. The accumulation of material to form planets in this way is called accretion.

  The temperature of the early Solar System explains why the inner planets are rocky and the outer ones are gaseous. As the gases coalesced to form a Protosun, the temperature in the Solar System rose. In the inner Solar System, temperatures were as high as 2000 K, while in the outer Solar System it was as cool as 50 K. In the inner Solar System, only substances with very high melting points would have remained solid. All the rest would have vaporized. So the inner Solar System objects are made of Iron, Silicon, Magnesium, Sulfur, Aluminum, Calcium and Nickel. Many of these were present in compounds with Oxygen. There were relatively few elements of any other kind in a solid-state to form the inner planets. The inner planets are much smaller than the outer planets and because of this have relatively low gravity and were not able to attract large amounts of gas to their atmospheres. In the outer regions of the Solar System where it was cooler, other elements like Water and Methane did not vaporize and were able to form the giant planets. These planets were more massive than the inner planets and were able to attract large amounts of Hydrogen and Helium gases and that is why they are composed mainly of Hydrogen and Helium, the most abundant elements in the Solar System and the whole of the universe.

 

9. Why is Venus the brightest planet of our Solar System?

Ans: Its atmosphere is primarily made up of Carbon dioxide gas that reflects most of the sunlight received from the Sun like a mirror. Therefore, the planet shines the brightest.

10. Why Neptune is the windiest planet of the Solar System?

Ans: Neptune radiates more heat than it receives because it has an immense internal source of energy. Its internal heat source adds to the vertical convection, extreme wind speeds and the overall dynamics of the planet.  

11. Why the planets do not twinkle like the stars?

Ans: Planets do not twinkle like stars, because they appear larger discs of light due to their close distance from the Earth.  Hence, the shift in their light rays reaching our eyes due to atmospheric refraction is smaller. The shift is not enough for the planets to twinkle. (Due to atmospheric refraction, the light rays coming from a star bends as they pass different layers of our atmosphere and, further,  the amount of this bending continuously shifts in direction as the optical properties of these layers keep on changing abruptly due to the turbulences created because of temperature fluctuations.  

12.  What is Asteroid Belt and what is its use in the Solar System?

Ans: The asteroid belt is a region of space between the orbits of Mars and Jupiter where most of the asteroids in our Solar System are found orbiting the Sun. The asteroid belt probably contains millions of asteroids and minor planets forming a disk around the sun. It also serves as a sort of dividing line between the inner rocky planets and outer gas giants. The classical view is that the asteroid belt formed within the gassy, dusty disc swirling around the primordial Sun, like a swarm of leftover planetesimals, with an initial mass of perhaps several Earth masses in total. The presence of an asteroid belt at the place where it now keeps a balance of gravity between the rocky planets and the gaseous giants. If a planet were in the place of the asteroid belt, that gravitational balance would not have been maintained and our Solar System would have been unstable!

13. What are Craters and why does the Moon have so many craters unlike our Earth?

 Ans: The craters are holes created on the surface of planets and their satellites due to the impact of meteorites from space. Yes, The Moon has too many craters; these are indeed meteorite impact craters. This is due to the fact that, unlike the Earth, the Moon has no atmosphere to protect itself from impacting bodies. It also has very little geologic activity (like volcanoes) or weathering (from wind or rain) so craters remain intact for billions of years.

 

14. Why is Venus called The Twin Sister of Earth?

Ans: Venus is called the twin Sister of Earth' because it has almost the same size as that of the Earth. 

 15. Which planet is the heaviest one?

Ans: Jupiter, being the largest planet of our Solar System, is the heaviest one. 

16.  Is there a planet that rotates up or down instead of left to right or right to left ?

Ans: Yes, there is indeed one such planet in our Solar System. The planet Uranus axis is highly tilted from the normal to its orbital plane and it almost points towards the Sun.  This is as if the planet lies on its sides on the orbital plane and still spinning about this axis. One of the consequences of this highly tilted axis of Uranus is that the duration of the seasons on the planet is unusually very long!  

16.  What would happen if Earth rotated at the speed of light?

Ans: If the Earth rotated at the speed of light ( i.e. 299,792 km/sec) that would be 652,000 times faster than today, the dimensions of the planet would change. Once in the form of a sphere, the Earth would shrink into a thin disc-like shape. So do you, with every other thing. You could say that it had become a flat earth! Secondly, the  Earth could become a tiny black hole,  because an object moving at the speed of light has an infinitely huge mass. Thirdly, the change of day and night will be very fast as it depends on the speed of rotation of the planet about its axis. Daytime will be infinitely short and the same will happen for the night as well. Lastly, rotating at this extreme speed would distort time on Earth according to the theory of Relativity. It will slow down so much that it will eventually stop. You will freeze in time! In all, the chance of surviving on the Earth would have become very small.

17. Why does Venus show phases like the Moon ?

Ans: Only the planets  Mercury and Venus, the two interior planets to the Earth, can show phases like the Moon. This is because, as the planet revolves around the Sun, we view it at different angles at different times.  Therefore, we see different portions of its lighted surface pointed towards the Earth at different times due to the changing relative positions of the planet, Sun and the Earth. This gives rise to different phases of Venus seen at different times. 

      However, we are not able to see the phase of an exterior planet like Mars or Jupiter. For the outer planets, we don’t have a good angle to see the “back” side of the planet, so we see the outer planets as fully or mostly lit up, with no or very little lighted surface. So they don’t show dramatic phases in the same way.

17. What would happen if our Earth were sucked by a Blackhole?

Ans: First, the materials from the Earth would be pulled towards the hole spiraling inwards with such an immense velocity that it will be tremendously heated to emit X-rays. Secondly, the Earth would be pulled apart to become shattered into pieces due to the Tidal effect as the edge of the Earth closest to the black hole would feel a much stronger force than the far side because of sharp variations of the Black hole’s gravity within a short distance. In that case, the Earth would lose its atmosphere and waters in the seas and our bodies would be enormously stretched and torn apart with immense force. Thirdly, the strong uneven gravitational pull on the Earth would continuously deform the planet. This would generate a tremendous amount of internal friction, heating the Earth’s core to disastrous levels. This would likely give rise to Earth-shattering earthquakes, volcanoes, and deadly tsunamis.  Our chance of surviving on Earth would become very less if ever that unfortunate event happens!

 

ADDITIONAL LINKS

1. PPT  'OUR SOLAR SYSTEM'  ( Class: 5 to 8)

Link : https://tinyurl.com/solar-slide

2.  QUIZ ON 'OUR SOLAR SYSTEM' ( Class 5 to 8)

Link for the Quiz: https://forms.gle/XC13pRpMUvqy7T4SA