Study of Characteristic of Tsunami in north Donggala, Central Sulawesi

Pray for Palu and Donggala

We know that in the past few days, there  were earthquake and tsunami in Palu and Donggala, Indonesia. I was so sad as an indonesian. Although I don't live in Palu or Donggala, but I feel pain like my brothers feel it in Palu and Donggala. I can help them just only according to what i can do and keep praying for them.

The Planet Pluto and The Charon

Pluto & Charon

From the surface of the planet Pluto, we look up at Charon in the sky, 20 times closer to pluto than our Moon is to Earth. It is an impressive sight. Charon may rank twelfth in size among moons in the solar system, but it is so close to Pluto-only 11,650 miles (18,800 kilometers) above Pluto's equator-that it appears larger than any other moon appears from the surface of its planet. Charon covers almost 4 degrees in Pluto's sky-eight times as wide as our Moon appears from Earth. On our planet, you can hold a pea out at arm's length and completely eclipse our Moon. On Pluto, to block Charon from view, you would need a billiard ball.

It was no surprise that Charon rotates in the same period of time as it revolves so that it always presents the same hemisphere to Pluto. All the inner satellites and all the major satellites in the solar system have synchronous rotation and revolution because they are tidally coupled to their planets. A planet's gravity creates a slight tidal bulge in its moons and pulls on that bulge so that the moons cannot turn it away from the planet. One side of the satellite always faces the planet and the other side always faces away while the planet rotates rapidly, so that the moon rises and sets for all parts of the planet. But, Pluto furnished a surprise. Pluto and Charon are so close to twins in size and so close together that Charon's gravity induces a bulge in Pluto. The bulge is great enough that pluto is tidally coupled to Charon just as Charon is tidally coupled to Pluto. Thus, Pluto always shows the same face to Charon just as Charon always shows the same face to Pluto. It is the only example of mutual tidal coupling in the solar system. The result is that for an astronaut standing in Pluto, Charon is either always visible or never visible.

The shadows we see on Charon reveal an uneven, cratered landscape. Like Pluto, Charon is light gray, although somewhat darker and more even in color than Pluto, as was know from measurements made from Earth using the Pluto-Charon eclipses. The very slightly reddish brown hue of Pluto is missing from Charon-or at least from Charon's Pluto-facing side, that is the only side we get to see from the surface of Pluto. Missing too from Charon is the methane frost which partially covers Pluto. With Charon's smaller mass and therefore weaker gravity, whatever methane ice there was at the surface has evaporated. Perhaps this in part explains why Charon is less reflective. The escaping methane has exposed frozen water to view.

On Earth, we are used to rising and setting of the Sun, Moon, and stars as our planet turns. On Pluto, the Sun rises and sets, if somewhat slowly, but Charon stays fixed in the sky. It never rises or sets, thanks to tidal coupling. As Charon revolves once around Pluto in 6.4 days, Pluto spins once around on its axis in that same period of time. The result is that Charon hangs almost stationary in the sky while the Sun and Stars glide slowly past in the background. Because Charon is so large in the sky, stars are frequently blocked from view. These stellar occultations are the only eclipses visible during the 120-year gap between seasons of solar and lunar ecplipses.

From the vantage point of Earth, Pluto and Charon pass in front of and behind one another very  rarely. The Earth experiences solar and lunar eclipses at least four times and sometimes as many as seven times a year. Because of Pluto's axial tilt and Charon's position over Pluto's equator, the pair goes for almost 120 years without their shadows ever falling upon one another. Then, in a period roughly six years long, Charon's orbit is nearly edge on to Earth and every 6.39-day orbit Charon makes carries it across the face of Pluto and then around behind Pluto. The result is an eclipse frenzy. Serendipitously, that eclipse season began in 1985, soon after Charon was discovered.

During an eclipse of the Sun on Pluto, Charon would look like a giant dark hole in the sky, marked only by the absence of stars. It would be dark but not black because it would be illuminated be reflected light from Pluto. The corona-the outer atmosphere of the Sun, which makes solar eclipses seen from Earth so beautiful-would be visible only just after the Sun vanished and just before it reappeared. At mid-eclipse, the disk of Charon covers the entire orbit of the Earth. The corona is far too faint at that distance from the Sun to peer around the edges of Charon.

Global Warming, Is It an end to our World?

Glacier, Argentina, South America

The devastating impact of global warming is already evident everywhere in the world, as also in Indonesia. If warming continues at this rate, can you imagine what will be the condition of Indonesia 10 to 15 years from now?

There is irrefutable evidence that human activity since the industrial revolution has changed the atmosphere of our earth and continues doing so. Since the time we started industrializing, we started polluting; polluting our waters, our air, releasing greenhouse gases that contribute towards global warming. Human activity will continue to affect out our earth but we need to make changes before our earth succumbs to the pressures of global warming and disappears altogether.

According to a research by Greenpeace, there is extensive deforestation being carried out in Indonesia; half of the tropical rainforests have been destroyed. We are either bulldozing our burning thousands and thousands of acres of tropical forests in order to grow crops. Are we growing these crops to feed our own people? No, these acres and acres of forestland are used to grow crops like palm oil, palm sugar, and coffee - the lifeline of western food industries.

Forests are lungs of our earth. Trees store carbon dioxide and release it as oxygen. Since there are not enough trees left to absorb the huge amounts of carbon dioxide produced, it disrupts the natural balance and contributes towards climatic changes, which is a consequence of global warming (Green peace report, 2007).

The impact of climatic change is noticeable throughout Asia-Pacific by simple observation. Either there are extremely hot days or too much rain accompanied by wind and thunderstorm that disrupts the daily activities. Experts are of the opinion that these changes will continue to happen more often. Furthermore, the shifting weather patterns have made it extremely difficult to predict the climate. Scientists have predicted long term disastrous effect on economy and on the people of Indonesia. More studies have shown drastic climate change will start in 2020. They are of the opinion that the random floods or dry season we see in Indonesia now will become a norm in 2020 (Reuters, 2007).

Moreover, experts are of the opinion that rapid onset of the climate changes will threaten the biodiversity. Due to extreme climates the catches of fish would decrease as much as 40% in Indonesia. Reaserch has shown that majority of people in Indonesia depend on the sea for their livelihood; those people will be drastically affected, as will be the economy of the country (Green peace report, 2007).

Additionally, shifting weather patterns have made it difficult for farmers to decide when to plant crops which in turn has led to major crop failures. A recent study has shown that Indonesia has a loss of 300,000 tons of crop production every year that is three times the loss in previous decades. It is impossible to say how this change will affect the long-term viability of palm oil and other commodities but it will certainly have a disruptive impact (Reuters, 2007)

Eventually global  warming will not only affect economy, but it will also affect the health people. It is predicted there will be dramatic increase in death toll. People will die due to floods, extreme heat, heat waves and storms. Due to the change, the bacteria and viruses will also mutate and a lot of incurable diseases will be responsible for deaths of millions of people (Science Daily, 2007)

Global warming is not a new problem nor is Indonesia solely responsible for it. But as it is, Indonesia will be among the most vulnerable as it is one of the greenhouse gas emitter after china and USA. The goverment of Indonesia recognizes that it is a huge issue that will affect us if attention is not paid to it. The goverment is making every possible effort they can to tackle this issue but we have to do our part.

thanks for reading, read this article too The Planet Pluto and The Charon