One of the important things we've determined is stars don't all form at the same time. The earlier stars tend to have an influence on the later ones.

Ned Ladd

Wishes may be forever, but the stars we hang on them are not. Instead, new stars are constantly forming as others die off. Astronomer Ned Ladd studies how stars are born out of the remnants of their predecessors.

"As stars die, they tend to blow up and all the pieces get spread out over space," says Ladd. As the pieces cool off, they form giant clouds of gas and dust tens of light years across that eventually start to contract and form the next generation of stars. That's the stage where Ladd's research begins.

"The process I look at is the contraction of those clouds – how long it takes, what kinds of stars get made, whether it is a bunch of little stars, or fewer large stars," Ladd says.

Stars tend to form in groups, so astronomers have asked whether the formation of one star influences its neighbors. "One of the important things we've determined is they don't all form at the same time," Ladd says. "The earlier stars tend to have an influence on the later ones." 

Each time a star forms, wind blows outward from the collapsing star with enough force to push around any nearby material. Whether this disruption reduces the number of stars that form out of a given region, by pushing the material apart, remains to be answered.

In addition to understanding the universe itself, Ladd is also studying new ways to make the universe comprehensible to others. The same concept that gives astronomy its popular appeal – the vast openness of space – also proves difficult for most people to fully grasp. 

"Students and people in general have a hard time visualizing the scale of the universe," Ladd says. "It is hard to get people to really understand how big and how empty the universe is."

Ladd, along with education professor Katharyn Nottis, and a colleague at Harvard recently received a grant from the National Science Foundation to develop new ways to teach the concepts of size and scale in introductory astronomy classes. The researchers are developing exercises using Microsoft's free, online World Wide Telescope visualization software, which enables users to virtually fly through the universe, zooming in and out and visiting features along the way.  

Ladd also enjoys inviting the public to explore astronomy at events that fuse art and science. In the winter, Family Night provides children's activities, storytelling, folk singing and the chance to peer through the observatory telescopes. In the summer, Music in the Dark provides a coffee house atmosphere with a jazz quartet and telescopes on the Quad. 

"We saw an opportunity to connect science with the community and with all the other ways that people look at the world," Ladd says. "I wish we could do more of it."

Posted September 26, 2013