Kevin Hainline
@kevinhainline.bsky.social
Enthusiastic Astronomer. Professor at the University of Arizona. I use telescopes to find things. (He/him)
this is from a paper I'm putting together of a 300 K brown dwarf and it's kind of insane how similar it is
November 11, 2025 at 12:59 AM
this is from a paper I'm putting together of a 300 K brown dwarf and it's kind of insane how similar it is
I want to fit this cocoa price chart and determine the effective temperature of this obvious Y dwarf, I might see phosphine absorption halfway through 2024
November 11, 2025 at 12:56 AM
I want to fit this cocoa price chart and determine the effective temperature of this obvious Y dwarf, I might see phosphine absorption halfway through 2024
Oh wow, it’s exciting (and intimidating!) to be on such a big stage for this talk!
October 28, 2025 at 7:35 PM
Oh wow, it’s exciting (and intimidating!) to be on such a big stage for this talk!
I'm a life-long Star Trek fan. Here's me, as a child, dressed as Data, wearing a costume my mom sewed, with my little brother. And here's me also, a few years ago, talking with John de Lancie (Q!) on stage at an event, giddy to be so close to someone so omnipotent.
October 27, 2025 at 4:44 AM
I'm a life-long Star Trek fan. Here's me, as a child, dressed as Data, wearing a costume my mom sewed, with my little brother. And here's me also, a few years ago, talking with John de Lancie (Q!) on stage at an event, giddy to be so close to someone so omnipotent.
we have steely dan at home
October 13, 2025 at 3:25 AM
we have steely dan at home
Finally, with our sample and some from the literature, we can look at the number of these very cold brown dwarfs in a given volume of space as a function of both temperature and height above the galaxy. This will help people with modeling the mass of the galaxy, and the distribution of stars!
October 2, 2025 at 2:59 AM
Finally, with our sample and some from the literature, we can look at the number of these very cold brown dwarfs in a given volume of space as a function of both temperature and height above the galaxy. This will help people with modeling the mass of the galaxy, and the distribution of stars!
We also see more proper motions for these brown dwarf candidates, where they are observed to move between images taken many years apart, which lends support to our claim that these aren't ultra distant galaxies, but much closer brown dwarfs.
October 2, 2025 at 2:59 AM
We also see more proper motions for these brown dwarf candidates, where they are observed to move between images taken many years apart, which lends support to our claim that these aren't ultra distant galaxies, but much closer brown dwarfs.
One interesting result from fitting these sources is that it looks like the brown dwarf atmospheric metallicity seems to decline for sources that are farther from the Milky Way disk, as we might expect, since these brown dwarfs are likely older, forming at earlier times. This is super neat!
October 2, 2025 at 2:59 AM
One interesting result from fitting these sources is that it looks like the brown dwarf atmospheric metallicity seems to decline for sources that are farther from the Milky Way disk, as we might expect, since these brown dwarfs are likely older, forming at earlier times. This is super neat!
Our fits are from a new fitting code I wrote with (my (former graduate student!) Jake Helton, Near Infrared Fitting for T- and Y-dwarfs, or NIFTY. It's Bayesian, and designed to fit NIRCam and MIRI data for brown dwarf candidates found in photometric data. It's here:
github.com/kevinhainlin...
github.com/kevinhainlin...
October 2, 2025 at 2:59 AM
Our fits are from a new fitting code I wrote with (my (former graduate student!) Jake Helton, Near Infrared Fitting for T- and Y-dwarfs, or NIFTY. It's Bayesian, and designed to fit NIRCam and MIRI data for brown dwarf candidates found in photometric data. It's here:
github.com/kevinhainlin...
github.com/kevinhainlin...
We find these cold brown dwarfs all over the place in the survey. Some of them are so cold that their surface is about the same as what Tucson can get to in the summer. This object, JADES-GS-BD-5, which we observe with NIRCam and MIRI, has a temperature of 322 K, or only 120° Fahrenheit (49° C)!
October 2, 2025 at 2:59 AM
We find these cold brown dwarfs all over the place in the survey. Some of them are so cold that their surface is about the same as what Tucson can get to in the summer. This object, JADES-GS-BD-5, which we observe with NIRCam and MIRI, has a temperature of 322 K, or only 120° Fahrenheit (49° C)!
I've taken quite an interest in finding these sources, since, with the depth of JWST NIRCam observations, you can find some really faint sources, many of which are stupendously cold. And a number are very distant - thousands of light years from the Earth, outside of the disk of the Milky Way.
October 2, 2025 at 2:59 AM
I've taken quite an interest in finding these sources, since, with the depth of JWST NIRCam observations, you can find some really faint sources, many of which are stupendously cold. And a number are very distant - thousands of light years from the Earth, outside of the disk of the Milky Way.
See, it turns out that when you have incredibly deep infrared observations of hundreds of thousands of distant galaxies, sneaking around in these data are these super cold "failed stars," known as brown dwarfs, which are the link between stars and planets.
October 2, 2025 at 2:59 AM
See, it turns out that when you have incredibly deep infrared observations of hundreds of thousands of distant galaxies, sneaking around in these data are these super cold "failed stars," known as brown dwarfs, which are the link between stars and planets.
it's a slow process but we can get it done
maps.app.goo.gl/w8N21QRLemP8...
maps.app.goo.gl/w8N21QRLemP8...
October 1, 2025 at 4:52 PM
it's a slow process but we can get it done
maps.app.goo.gl/w8N21QRLemP8...
maps.app.goo.gl/w8N21QRLemP8...
Today is my birthday, *and* it's a Pythagorean triple, 9 / 16 / 25. This sort of thing really got a lot of Greek mathematicians excited, until they had to reckon with what would happen to the length (c) if (a) and (b) were 1, that awful irrational square root of two.
September 16, 2025 at 6:14 PM
Today is my birthday, *and* it's a Pythagorean triple, 9 / 16 / 25. This sort of thing really got a lot of Greek mathematicians excited, until they had to reckon with what would happen to the length (c) if (a) and (b) were 1, that awful irrational square root of two.
A text from my father after they sat down to watch the video:
September 12, 2025 at 4:25 AM
A text from my father after they sat down to watch the video:
Last night, the Steward Observatory summer softball team (The "StrOHs") won the league championship game, 12-2. I've been playing summer softball through some good and a *lot* of bad years. It felt pretty damn great to win last night, capping a fun season. This was the StrOH's *first* championship!
August 6, 2025 at 7:40 PM
Last night, the Steward Observatory summer softball team (The "StrOHs") won the league championship game, 12-2. I've been playing summer softball through some good and a *lot* of bad years. It felt pretty damn great to win last night, capping a fun season. This was the StrOH's *first* championship!
My wife, before the pandemic, went on an American tour with them, playing keyboard and singing while they performed their poetry. I had a chance to travel with the tour for a brief few spots, and meet Andrea, their partner Megan, and their dogs.
July 14, 2025 at 5:17 PM
My wife, before the pandemic, went on an American tour with them, playing keyboard and singing while they performed their poetry. I had a chance to travel with the tour for a brief few spots, and meet Andrea, their partner Megan, and their dogs.
The poet Andrea Gibson passed away. They were an incredible writer, live performer, and their work had a huge impact on people around the world. I do a lot of these astronomy shows, and often I think about how I can soften the science, how I can make it something more like what I saw from Andrea.
July 14, 2025 at 5:17 PM
The poet Andrea Gibson passed away. They were an incredible writer, live performer, and their work had a huge impact on people around the world. I do a lot of these astronomy shows, and often I think about how I can soften the science, how I can make it something more like what I saw from Andrea.
Here's Dr. Helton, wearing the cap, and the (also Basquait-inspired) crown, complete with a pom-pom galaxy overdensity on top.
June 30, 2025 at 11:36 PM
Here's Dr. Helton, wearing the cap, and the (also Basquait-inspired) crown, complete with a pom-pom galaxy overdensity on top.
My grad student Jake Helton defended his PhD successfully today. I'm so excited for him to head on to Penn State for a postdoctoral appointment in the fall. At UofA, grad students are awarded crowns and capes for their PhD, and here's the elaborate History of the Universe cape I painted for him.
June 30, 2025 at 11:36 PM
My grad student Jake Helton defended his PhD successfully today. I'm so excited for him to head on to Penn State for a postdoctoral appointment in the fall. At UofA, grad students are awarded crowns and capes for their PhD, and here's the elaborate History of the Universe cape I painted for him.
the employee just stood at the window holding the empty cup upside down, looking very distraught. I got a picture of the carnage below
June 26, 2025 at 2:10 AM
the employee just stood at the window holding the empty cup upside down, looking very distraught. I got a picture of the carnage below
I made this diagram along with Stefano Carniani last year, and I think that JWST will see a similar early rise of rapid record breaking, maybe with a turnover at around z = 15 or 16. Who knows! It's fun to be watching history being made live over the last few years.
May 22, 2025 at 3:40 AM
I made this diagram along with Stefano Carniani last year, and I think that JWST will see a similar early rise of rapid record breaking, maybe with a turnover at around z = 15 or 16. Who knows! It's fun to be watching history being made live over the last few years.
had to paint them all individually, they were a very time intensive project to be eaten
May 18, 2025 at 9:08 PM
had to paint them all individually, they were a very time intensive project to be eaten
these are wonderful. Once I made ones a similar size, but they were marshmallows! Yum yum.
May 18, 2025 at 8:36 PM
these are wonderful. Once I made ones a similar size, but they were marshmallows! Yum yum.
It makes me pretty emotional, tbh, to play a part in someone’s academic journey. It’s very funny that we have these big moments like this in academia (even in the midst of extreme turmoil in the sciences) and we’re dressed like medieval dorks
May 17, 2025 at 3:34 PM
It makes me pretty emotional, tbh, to play a part in someone’s academic journey. It’s very funny that we have these big moments like this in academia (even in the midst of extreme turmoil in the sciences) and we’re dressed like medieval dorks