ScienceIQ.com

Mission: Gather Comet Dust; Return To Earth

One of the most imaginative NASA missions of recent years is the Stardust mission. Its main purpose: to gather dust and particles from comet P/Wild 2 and return them to Earth for study. Think about that for a second. We build a spacecraft, send it out past the orbit of Mars, a round trip of over seven years, to rendezvous with a comet only 4 km ...

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CometDust
Biology

Does Your Beagle Have A Belly Button?

Our navels, also know as belly buttons, are scars left over from our umbilical cords. While in the mother's womb, a baby receives food and oxygen and rids itself of waste through the umbilical cord. ... Continue reading

BeagleBellyButton
Biology

St. John's Wort

St. John's wort is an herb that has been used for centuries for medicinal purposes, including to treat depression. The composition of St. John's wort and how it might work are not well understood. ... Continue reading

StJohnsWort
Geology

What is an Estuary?

An estuary is a partially enclosed body of water formed where freshwater from rivers and streams flows into the ocean, mixing with the salty sea water. Estuaries and the lands surrounding them are ... Continue reading

WhatisanEstuary
Biology

What’s So Different About Ferns?

Most plants reproduce by producing a flower, then seeds. Anthers, considered the male reproductive structure, hold the pollen. The ovum, the female reproductive structure inside the flower, is ... Continue reading

Ferns

Will the Sun Shine Forever?

SunLifetimeThe Sun is a huge nuclear furnace. It operates by converting hydrogen into helium. In this process, which is called nuclear fusion, it loses mass and produces energy according to Einstein's famous equation: E=mc^2. This energy is dissipated in the form of light that we see and heat that we feel. In addition, some of this energy comes as X-rays, and a host of accelerated particles.

Our Sun has been converting hydrogen into helium for approximately 4.5 billion years. During this period it has converted 25% of its total mass into helium. About 75% of its mass is still hydrogen, and a very small remaining fraction accounts for oxygen, carbon and other elements. Based on a crude extrapolation, one would think that everything would be just fine for at least the next 13.5 billion years; however this is not the case.

The latest estimates show that our Sun will start dying approximately 5 billion years from now. What will happen to it? It will first gradually become brighter; in 5 billion years it will be about twice as bright as it is today. Then the internal energy from the fusion will start decreasing as the hydrogen becomes scarce. Gravity will win and the Sun's core will collapse on itself. This collapse will produce enough heat that the outer layers will expand violently, engulfing Mercury, stripping Venus of its atmosphere and scorching Earth. After this transformation, our Sun will be known as a red giant.