MyCn18 is a young planetary nebula, located about 8,000 light-years away. Planetary nebulae are shells of gas and dust, which stars eject when they run out of fuel. This Hubble image reveals the true shape of MyCn18 to be an hourglass with an intricate pattern of “etchings” in its walls (Image: Raghvendra Sahai and John Trauger (JPL) / WFPC2 science team / NASA) Our sun is a normal-sized star, but it will not remain in its current stable state for ever. Prominences like the one shown in this image are insignificant compared to the changes it will ultimately undergo (Image: SOHO Consortium / EIT / ESA / NASA) This artist’s impression shows a “red giant” star ejecting matter. Stars with masses close to that of our Sun become red giants in the later stages of their life. The radius of the star expands to a size comparable to the orbit of the Earth, and the matter at the surface of the star flows out and escapes (Image: JAXA) After the red giant stage, the star shrinks to a white dwarf. Such a star begins its life by casting off the cocoon of matter that enclosed its former self. This image shows the planetary nebula NGC 2440, which contains one of the hottest white dwarfs known. The white dwarf can be seen as the bright dot near the centre. Our Sun will eventually become a white dwarf, but not for another 5 billion years (Image: H Bond (STScI) / R Ciardullo (PSU) / WFPC2 / HST / NASA)
The Helix Nebula (NGC 7293) is a planetary nebula, consisting of shells of gas and dust…
Space
How will the solar system end?
28 January 2009
