2026 April 05 - NGC 3310: A Starburst Spiral Galaxy

0:00Greetings and welcome to the Astronomy picture of the day podcast. Today's picture is titled NGC3310, a starburst spiral galaxy. So what do we see here? Well, here we see a spiral galaxy and it may not look as grand as some of the spirals we occasionally look at. But it does have distinct spiral arms coming out from the center, as well as blue stars showing star formation, as well as red hydrogen regions, all the telltale signs that were used to looking at as star forming regions. Now it's called a starburst spiral galaxy, meaning that it is undergoing a burst of star formation. And that can occur for several regions, but generally it has to do with the collision with another galaxy. So another galaxy passed too close to this one, passed through this galaxy, or just came too close enough to trigger excess star formation.

1:03Its gravitational field would cause gas and dust clouds to collapse. Now that happens all the time in a spiral galaxy, but when you have that extra gravitational force from another galaxy, that will do it as well. That will enhance the star formation and make it much stronger than it otherwise would be. So what we think happened here was maybe 100 million years or so ago, this galaxy collided with a smaller galaxy. Now you'd wonder maybe in 100 million years why you'd still see evidence of this, and that's because galactic time frames are very long. Collisions can take hundreds of millions of years, and the star formation left behind can last even longer. And that's partially because when star formation starts, it could trigger the process throughout the spiral galaxy. So one part of the galaxy can start it, and the shock waves from those stars that formed can continue the process.

2:05So we can go on long after the collision is done. Now we can also see some of the distortion around this also likely tied to that collision, that would distort some of the stars and distort the spiral arms within the galaxy. So galaxies do this through collisions. They very often will collide with one another, because they are relatively large compared to the distances between them. And that means that they will pass close together and will interact. And that includes our own Milky Way, which is in the process of consuming smaller galaxies which orbit it, and which is on a collision course with the Andromeda galaxy. So in another few billion years, we will be on a collision with the Andromeda galaxy, which will definitely change both of our two galaxies, eventually believe to merge them into one single larger galaxy. So that was our picture of the day,

3:06titled NGC3310, a starburst spiral galaxy. We'll be back again tomorrow for the next picture, previewed to be horse head high. So we'll see what that is about tomorrow. And until then, have a great day everyone, and I will see you in class.