Danny Milisavljevic's Avatar

Danny Milisavljevic

@danmil.bsky.social

Associate Professor of Physics and Astronomy at Purdue University. Excitable Explorer of the Universe.

718 Followers  |  842 Following  |  111 Posts  |  Joined: 25.08.2023  |  1.7601

Latest posts by danmil.bsky.social on Bluesky


Supernova 1987A is located in the centre of the image amidst a backdrop of red, blue, and orange stars. A bright pink and red ring around the central region of the exploded star is composed of material ejected by the star about 20 000 years before the actual explosion took place. The supernova is surrounded by red and orange gaseous clouds. The color of these clouds represents the glow of hydrogen gas.

Supernova 1987A is located in the centre of the image amidst a backdrop of red, blue, and orange stars. A bright pink and red ring around the central region of the exploded star is composed of material ejected by the star about 20 000 years before the actual explosion took place. The supernova is surrounded by red and orange gaseous clouds. The color of these clouds represents the glow of hydrogen gas.

Light from supernova 1987A reached Earth #OTD in 1987.

The Hubble space telescope captured this spectacular image for the 30 year anniversary in 2017. ๐Ÿงช ๐Ÿ”ญ โš›๏ธ

Credits: NASA, ESA, R. Kirshner (Harvard-Smithsonian CfA, Gordon and Betty Moore Foundation), M. Mutchler and R. Avila (STScI)

23.02.2026 14:52 โ€” ๐Ÿ‘ 133    ๐Ÿ” 41    ๐Ÿ’ฌ 3    ๐Ÿ“Œ 3

This brings back many memories!

13.02.2026 23:46 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

My wife says this is what I look like cooking in the kitchen.

08.02.2026 18:19 โ€” ๐Ÿ‘ 2    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

The ice breaker question I often ask at nerdy parties is this:

What code or latex editor do you use?

My answer: vi for most editing. Emacs for lengthy code and most latex documents.

Answers involving web browsers are hard to accept. I love when someone brings up something random like nano.

14.12.2025 12:10 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0

This hits hard!!! I recently edited a latex file offline using emacs, and it was so much swifter and less cumbersome than Overleaf. Itโ€™s unfortunate that many students know only write using online tools.

14.12.2025 12:00 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

I hear the same concerns from undergraduates.

07.12.2025 15:36 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0
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Satellite megaconstellations will threaten space-based astronomy - Nature Rapidly growing satellite constellations pose a substantial threat to astronomical observations, with projections indicating that future space telescopes will have more than 96% of their exposures aff...

You can access the article for free here:

www.nature.com/articles/s41...

(Sorry for the previous link which is broken!)

03.12.2025 21:05 โ€” ๐Ÿ‘ 79    ๐Ÿ” 39    ๐Ÿ’ฌ 2    ๐Ÿ“Œ 3

I love me mine! ๐ŸŒŒโ˜‚๏ธ

01.12.2025 16:20 โ€” ๐Ÿ‘ 2    ๐Ÿ” 1    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

Sad to realize that 80% of people in North America canโ€™t see the Milky Way at night.

We need these protected Dark Sky escapes to connect with the Universe.

25.11.2025 01:05 โ€” ๐Ÿ‘ 4    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

I haven't seen research though I'd guess it exists, but handwriting letters *extensively* - as in 18th & 19th centuries- seems to produce a critical mass of great writers & thinkers. Jefferson's correspondence with Adams, for example. Maybe it's quill pens, which slow down writing to thinking speed.

21.11.2025 13:53 โ€” ๐Ÿ‘ 10    ๐Ÿ” 2    ๐Ÿ’ฌ 2    ๐Ÿ“Œ 0

Yes to this also! Everyone has different strategies to learn.

Iโ€™m reminded of a saying from my dad:
โ€œIf you do nothing, you know nothing.โ€

I can read all about, e.g., basketball, but unless Iโ€™m on the court practicing shots, Iโ€™m not going to improve my game.

21.11.2025 13:48 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

I remember the โ€œold fashioned library searchโ€

21.11.2025 13:08 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0

Same reason why I tell students to consider writing notes instead of typing them in class: numerous studies show that actively synthesizing information (a necessity from slower writing) is superior to more extensive but passive notetaking when it comes time to recall and interpret content.

21.11.2025 13:06 โ€” ๐Ÿ‘ 36    ๐Ÿ” 0    ๐Ÿ’ฌ 3    ๐Ÿ“Œ 0
Preview
Webb First to Show 4 Dust Shells 'Spiraling' Apep, Limits Long Orbit - NASA Science NASAโ€™s James Webb Space Telescope has delivered a first of its kind: a crisp mid-infrared image of a system of four serpentine spirals of dust, one expanding

Very excited to share the NASA/ESA/STScI press release of our team's work on Apep! It's a terrific writeup, complete with a brand new beautiful visualisation of the nebula geometry.
1/? โš›๏ธ๐Ÿ”ญ๐Ÿงช
science.nasa.gov/missions/web...

19.11.2025 22:07 โ€” ๐Ÿ‘ 549    ๐Ÿ” 128    ๐Ÿ’ฌ 9    ๐Ÿ“Œ 22
Snapshot of a part of Euclid VIS detectors, almost saturated with cosmic ray hits.

Snapshot of a part of Euclid VIS detectors, almost saturated with cosmic ray hits.

Those were beautiful #aurorae in the past days. A solar storm brought a lot of protons to Earth. Not only to Earth but also to #ESAEuclid โ€“ but does #Euclid notice? Oh yes.

www.euclid-ec.org/here-comes-t...

#ESA #Sun #SpaceWeather #space

15.11.2025 15:52 โ€” ๐Ÿ‘ 79    ๐Ÿ” 32    ๐Ÿ’ฌ 3    ๐Ÿ“Œ 6

How did I not know this?!

07.11.2025 22:50 โ€” ๐Ÿ‘ 4    ๐Ÿ” 1    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0
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Astronomers have spotted the largest and most distant flare ever observed from a supermassive black hole.

Nicknamed โ€œSuperman,โ€ the flare originated 10 billion light-years from Earth, and at its peak, the light emitted shone with the brightness of 10 trillion suns. https://cnn.it/3WFwNNN

07.11.2025 01:04 โ€” ๐Ÿ‘ 174    ๐Ÿ” 47    ๐Ÿ’ฌ 8    ๐Ÿ“Œ 16

Another title for this article could be: โ€œSuperman Outshines Scary Barbieโ€

www.cnn.com/2025/11/06/s...

07.11.2025 01:22 โ€” ๐Ÿ‘ 13    ๐Ÿ” 10    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
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An Extremely Luminous Flare Recorded from a Supermassive Black Hole Since their discovery more than 60 years ago, accreting supermassive black holes in active galactic nuclei (AGN) were recognized as highly variable sources, requiring an extremely compact, dynamic env...

Excellent, exciting new paper by M. Graham et al. who find the newest record holder for most energetic flare from a supermassive black hole, nicknamed โ€œSupermanโ€. The previous record holder was โ€œScary Barbie,โ€ first reported by our group at Purdue in Subrayan et al. 2023.

arxiv.org/abs/2511.02178

07.11.2025 01:08 โ€” ๐Ÿ‘ 6    ๐Ÿ” 1    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 2
Figure showing the proposal counts for Cycle 5, tracking above Cycle 4 by a few hundred.

Figure showing the proposal counts for Cycle 5, tracking above Cycle 4 by a few hundred.

So, we are tracking well above Cycle 4. Figure by @mpudoka.bsky.social and Yongda Zhu. ๐Ÿ”ญ

15.10.2025 20:16 โ€” ๐Ÿ‘ 41    ๐Ÿ” 7    ๐Ÿ’ฌ 4    ๐Ÿ“Œ 4

I thought loopnet was only a place to find office and warehouse space!

16.10.2025 01:20 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
Amateur image of NGC 7531 (left). DESI Legacy Imaging Survey image of NGC 7531 (right). Sky-subtracted image of NGC 7531 as
processed by Gnuastroโ€™s NoiseChisel program was used as a basis for photometry measurements. Features are labelled: (a): main shell; (b): faint
outer shell; c: counter plume.

Amateur image of NGC 7531 (left). DESI Legacy Imaging Survey image of NGC 7531 (right). Sky-subtracted image of NGC 7531 as processed by Gnuastroโ€™s NoiseChisel program was used as a basis for photometry measurements. Features are labelled: (a): main shell; (b): faint outer shell; c: counter plume.

Michelle's first paper discusses the Pearl in the Shell, a study of an ultra compact dwarf and a debris cloud around a nearby spiral galaxy. The study combines data from professional and amatCheck it out in our latest episode! arxiv.org/abs/2509.14038 ๐Ÿ”ญ โ˜„๏ธ

29.09.2025 08:36 โ€” ๐Ÿ‘ 24    ๐Ÿ” 4    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 1

Excellent morning read. Thanks for sharing!

28.09.2025 13:02 โ€” ๐Ÿ‘ 2    ๐Ÿ” 1    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

I love this photo!!! ๐Ÿ˜ Itโ€™s amazing. Thank you for sharing!

25.09.2025 19:23 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
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Wilbur, this morning!

25.09.2025 13:06 โ€” ๐Ÿ‘ 2    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
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Happy Miniature Schnauzer Day!

I asked Google โ€œWhatโ€™s your favorite dog?โ€ and it came back with Miniature Schnauzerโ€”like our Wilbur.

A+ to whoever trained this LLM. ๐Ÿง‘โ€๐Ÿ’ป๐Ÿพ

Does your smart assistant agree?

25.09.2025 13:03 โ€” ๐Ÿ‘ 2    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
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Wilbur hopes you get well soon!

21.09.2025 14:59 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
Three canvas-like prints of star clusters and neabulae on a dark purple wall.

Three canvas-like prints of star clusters and neabulae on a dark purple wall.

A canvas print of Cas A on a dark purple wall.

A canvas print of Cas A on a dark purple wall.

A placard for the Cas A canvas. Of importantance to this post, it shows credit to Danny Milisavljevic (of course, among others).

A placard for the Cas A canvas. Of importantance to this post, it shows credit to Danny Milisavljevic (of course, among others).

was v excited to see work by @danmil.bsky.social (+ many others!) featured at the @amnh.org today !!

18.09.2025 21:38 โ€” ๐Ÿ‘ 20    ๐Ÿ” 2    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0
JWST captured this sparkling scene of star birth in Pismis 24, a young star cluster about 5,500 light-years from Earth in the constellation Scorpius. This region is one of the best places to explore the properties of hot young stars and how they evolve.

JWST captured this sparkling scene of star birth in Pismis 24, a young star cluster about 5,500 light-years from Earth in the constellation Scorpius. This region is one of the best places to explore the properties of hot young stars and how they evolve.

This new JWST image is one of the most spectacular yet from the space telescope.

Giant, newborn stars here are carving away surrounding gas & dust. The bright pair at center is two of the most massive stars known. The dark spire is 50 trillion kilometers tall! ๐Ÿงช๐Ÿ”ญ

webbtelescope.org/contents/new...

04.09.2025 21:40 โ€” ๐Ÿ‘ 147    ๐Ÿ” 44    ๐Ÿ’ฌ 5    ๐Ÿ“Œ 2
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Rainer Weiss, Who Gave a Nod to Einstein and the Big Bang, Dies at 92

Obituary in NY Times

www.nytimes.com/2025/08/26/s...

27.08.2025 10:55 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

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