Astronomical insights from visiting prof
GAZING into the beginnings of the universe is all in a day’s work for a leading American astronomer.
An audience at Otago Museum yesterday was treated to a journey through galaxies by Michigan State University astronomy and astrophysics professor and American Astronomical Society president Megan Donahue.
She spoke about how researchers knew about the composition of galaxies and the rips in the universe called supermassive black holes which are thought to hold those galaxies together.
‘‘One of my research activities is how supermassive black holes regulate the growth of the galaxy around it.’’
She also spoke of the Hubble Space Telescope and how the further away it looked, the further back in time the light came from.
This meant some of the images showed light from near the ‘‘beginning of time’’.
‘‘Sometimes you . . . [think] this galaxy is sitting only 400 million years after the universe was formed, keeping in mind the universe was created more than 13 billion years ago.
‘‘So that’s the first 10% of the universe’s life. That seems a little mindbendy.’’
When the James Webb telescope became operational in 2021 it would be able to take images of the first galaxies and stars ever created, she said.
Prof Donahue is in New Zealand on holiday with her family.
One of the biggest findings in her field in recent years was the detection of gravitational waves, she said.
These were ripples in the fabric of the universe caused by the collision of massive objects, predicted by Albert Einstein 100 years ago.
‘‘That’s gigantic. That is the first solid indication that there’s this whole different way of looking at the universe and we’re just beginning.’’
Sometimes Prof Donahue did step back and take stock of the impacts of the findings in her field.
‘‘You do sometimes just think ‘wow’.’’