Lee-Waddell and her team discovered what they believe to be a new tidal dwarf galaxy. These galaxies are rare because they form from two larger “parent” galaxies.
“Normally when galaxies form they collapse from giant gas clouds, and for a long time this is the way people thought all galaxies were formed,” Lee-Waddell said. “We’re used to studying galaxies that merge and get bigger and now we’re seeing smaller ones.”
The theory is that the smaller tidal dwarf galaxies, such as the one that Lee-Waddell discovered, are created when material branches out of two proximate galaxies and spirals together without the presence of dark matter gravity.
It is difficult to confirm when a galaxy is in fact a tidal dwarf galaxy. Lee-Waddell said that since they were discovered in the 70’s there have only been two or three galaxies that have been definitively confirmed.
“The next step is to get more data, metallicity data,” Lee-Waddell said with a sigh.If the metallicity, or composition of the material in the galaxy, matches the two neighbouring parent galaxies then it is more likely to be a tidal dwarf galaxy. The finalization will come in due time — Lee-Waddell said it would take about two years to gather the metallicity data, accounting for booking telescope time and proper weather conditions.
Since the discovery, Lee-Waddell has been interviewed by national news outlets and has attended conferences around the continent. She was still excited to speakabout her galaxy, named AGC208457, and the future implications of this discovery.
Catherine Owsik: If the metallicity data shows that AGC208457 isn’t made up of the proper parent materials to make it a tidal dwarf galaxy, what could it be?
Karen Lee-Waddell: We wouldn’t know. It’s so unusual … if this galaxy formed with no dark matter we assume it pulled its stuff from its parents and it didn’t need extra gravity — but if it didn’t, and it has no dark matter [which would create gravity], then it’s really weird — and that kind of supports other theories of modified gravity and other hypotheses of what is
If it turns out to not be a tidal dwarf galaxy, would you continue to investigate its origins?
Yes, it would be really interesting. That would be a big support to the theory that all our science and physics is wrong.
How did you come to study astronomy?
When I was about six years old I was coming home in my sister’s car and she had a sunroof … it was night and she started telling me all these constellations, and by the time I was 10 I had telescopes … but I grew out of it and eventually wanted to become a lawyer.
Then in high school I was doing a law assignment, the most dull, boring law assignment, and I looked up and I saw my telescope. I grabbed it and went on the roof, and I never finished that law assignment. From there on it was always astronomy and physics.
Did you ever dream you would discover a galaxy?
No, I didn’t even think being an astronomer was plausible. I kind of wanted to be an astronaut and go into space, but observing is quite cool too because you actually see farther, and it’s a lot less rigorous.
I’m surprised, so even with military training [from previously studying at the Royal Military College] you don’t want to be an astronaut?
I might, that’s one of the reasons I joined the military. You know, to keep me in shape, the security clearances, and all that stuff. It’s always there. Most astronauts are like 40 years old anyways; it’s
I know the galaxy is named following a standard naming system – but if you could have named the galaxy anything, what would it be?
In my thesis it was named LW1 – or Lee-Waddell 1. So it incorporates Lee, because that’s my family’s name, and then my husband’s name Waddell.
So the “1” means it’s the first of many galaxies you will discover?
(Laughing) Well, yea.
What do you imagine the galaxy to be like?
It would be interesting because it’s a smaller galaxy which has really old and new stars … Everything is just really compact. So it would be like our galaxy but smaller and more dynamic.
Do you believe in alien life?
I believe that life can exist outside of Earth. Intelligent life, I hope there is, because that would be pretty cool. But I wouldn’t be afraid of them … if they’re smarter than us they’ll just drive by, but if they’re around the same level maybe they’ll come and talk.
By Catherine Owsik