Revealing pattern without planets - 0 views

• 
  #1 Sandra Flores on 05 Jan 15

   

  Revealing pattern without planets
  
  Planets around young suns are formed in a disk of gas and dust orbiting the star just created. Many such disks have now been detected around young stars. In some you even found peculiar structures such as rings or spiral pattern. They were many astronomers as an indication of the presence of a planet in the system of these structures can arise through its circulation.
  
  But how safe you can actually close of structures in dust and debris discs around young stars on existing planet? A new study warns of now of caution: Under the right circumstances, this "tell-tale pattern" births are completely without rotating planet. A corresponding journal article published this month in the scientific journal Nature.
  
  "If the mass of the gas in the disk is approximately equal to the mass of the dust interactions occur, which eventually lead to clumping of dust and the emergence of certain patterns," summarizes Wladimir Lyra's Jet Propulsion Laboratory together the results of the investigation. "In principle, the gas passes the dust in exactly the structures that we would expect if a planet in the system were in place."
  
  While warm dust around young stars using is relatively easy to detect by infrared observations, an estimate of the proportion of gas in a disk is much more difficult. So far, theoretical models have therefore mainly focused on the role of dust and ice particles in the discs and relatively little attention to the gas. However, ice particles can evaporate and also by collisions can occur gas so that simply must be assumed that a certain proportion of gas in the disk is available.
  
  "Everything we needed to give rise to narrow rings and other structures in our models of debris discs, was a little gas - enough to discover it with most of the systems available today," explains Marc Kuchner of the Goddard Space Flight Center of NASA.
      
  Advertising
      
  
  When ultraviolet light strikes from the central star on a speck of dust or a lump of ice, it can knock electrons from it. These electrons can then collide at high speed with gas particles in the environment and thereby heat the gas. But the increased gas pressure changes the resistance, which is the orbiting around the star dust exposed, so that the lump grows and thereby the gas can be heated more easily.
  
  

   

  <div class="cArrow"> </div><div class="cContentInner">Revealing pattern without planets <br /><br />Planets around young suns are formed in a disk of gas and dust orbiting the star just created. Many such disks have now been detected around young stars. In some you even found peculiar structures such as rings or spiral pattern. They were many astronomers as an indication of the presence of a planet in the system of these structures can arise through its circulation.<br /><br />But how safe you can actually close of structures in dust and debris discs around young stars on existing planet? A new study warns of now of caution: Under the right circumstances, this "tell-tale pattern" births are completely without rotating planet. A corresponding journal article published this month in the scientific journal Nature.<br /><br />"If the mass of the gas in the disk is approximately equal to the mass of the dust interactions occur, which eventually lead to clumping of dust and the emergence of certain patterns," summarizes Wladimir Lyra's Jet Propulsion Laboratory together the results of the investigation. "In principle, the gas passes the dust in exactly the structures that we would expect if a planet in the system were in place."<br /><br />While warm dust around young stars using is relatively easy to detect by infrared observations, an estimate of the proportion of gas in a disk is much more difficult. So far, theoretical models have therefore mainly focused on the role of dust and ice particles in the discs and relatively little attention to the gas. However, ice particles can evaporate and also by collisions can occur gas so that simply must be assumed that a certain proportion of gas in the disk is available.<br /><br />"Everything we needed to give rise to narrow rings and other structures in our models of debris discs, was a little gas - enough to discover it with most of the systems available today," explains Marc Kuchner of the Goddard Space Flight Center of NASA.<br />    <br />Advertising<br />    <br /><br />When ultraviolet light strikes from the central star on a speck of dust or a lump of ice, it can knock electrons from it. These electrons can then collide at high speed with gas particles in the environment and thereby heat the gas. But the increased gas pressure changes the resistance, which is the orbiting around the star dust exposed, so that the lump grows and thereby the gas can be heated more easily. <br /><br /></div>

  ...

  Cancel

To Top