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Andrew Fraknoi

@fraknoi

Semi-retired astronomer, college professor, lead author of a free, open-source textbook (OpenStax Astronomy), and science fiction writer with 8 stories published so far. See fraknoi.com

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23.11.2024
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Latest posts by Andrew Fraknoi @fraknoi

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Heads Up: Lunar Eclipse March 3
Total #lunareclipse coming early morning of March 3. Very democratic, everyone in N America can see. My explanatory sheet in everyday language: bit.ly/2026eclipse
#astronomy #astroed #science #scienceed #amateurastronomy #sky #eclipses #space #outerspace

18.02.2026 18:07 πŸ‘ 21 πŸ” 6 πŸ’¬ 1 πŸ“Œ 0
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Winter Solstice Arrives on Sunday Dec 21 We explain the reason for the seasons and what it means to have winter solstice.

Sunday is the Winter Solstice, the shortest day and longest night of the year. Why does our planet have seasons, when other planets like Venus and Jupiter do not? I posted a full explanation at: www.fraknoi.com/.../winter-s...
#astronomy #astroed #sky #scienceteaching #scienceeducation #science

19.12.2025 19:08 πŸ‘ 4 πŸ” 4 πŸ’¬ 0 πŸ“Œ 0
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The Lurker - The Worlds Within By Andrew Fraknoi Janice is asleep when I see the alien artifact. We are circling a small carbon-rich asteroid, evaluating whether its resources would be worth staking a claim, when I glimpse the unus...

Nice surprise. The editor of Worlds Within magazine nominated my science-fiction story "The Lurker" for a Pushcart Prize. It's about a probe from another civilization waiting on an asteroid; at: theworldswithin.net/the-lurker/
#sciencefiction #SETI #astroedu #science&fiction #science #astronomy

07.12.2025 17:53 πŸ‘ 11 πŸ” 3 πŸ’¬ 1 πŸ“Œ 0
The 2025 Andrew Fraknoi Award for Outstanding Support of the Astronomical Society of the Pacific and its work on science education goes to Dr. Connie Walker of the National Optical Astronomy Observatories (now known as NOIRLab)

The 2025 Andrew Fraknoi Award for Outstanding Support of the Astronomical Society of the Pacific and its work on science education goes to Dr. Connie Walker of the National Optical Astronomy Observatories (now known as NOIRLab)

Sat night, the #astrosociety of the Pacific gave the 2025 Fraknoi Award for extraordinary support of the Society's educational work to Connie Walker of #NOIRLab For more on her work see: bit.ly/2025fraknoia...
#astronomy #astroedu @conniewalker.bsky.social #lightpollution #scienceawards

10.11.2025 19:35 πŸ‘ 11 πŸ” 0 πŸ’¬ 1 πŸ“Œ 0
The course on atomic science is for everyone.  It will use historical anecdotes, analogies from everyday life, thought experiments, and touches of humor.

The course on atomic science is for everyone. It will use historical anecdotes, analogies from everyday life, thought experiments, and touches of humor.

Teaching a fun, illustrated Zoom course on atomic science for poets (meaning everyone.) Tuesdays Oct & Nov through the SF State OLLI program. For details & how to register: bit.ly/atomscourse
#science #physics #atomic #scienceeducation #astroedu #onlinecourses #Zoomcourses #sciencefiction #quantum

20.09.2025 17:29 πŸ‘ 11 πŸ” 7 πŸ’¬ 0 πŸ“Œ 0
In the cartoon, the man says, "I can't believe that summer, and civilization, are almost over."

In the cartoon, the man says, "I can't believe that summer, and civilization, are almost over."

This wonderful cartoon was sent out today in an email from The New Yorker magazine. All teachers will especially appreciate this.
#cartoons #teaching #astroedu #education #teachers #politicalcartoons #humor

19.08.2025 20:17 πŸ‘ 55 πŸ” 18 πŸ’¬ 1 πŸ“Œ 1
This graphic showing a rocket reads "science fiction."  I am an astronomer writing scientifically reasonable science fiction stories, with eleven published so far.

This graphic showing a rocket reads "science fiction." I am an astronomer writing scientifically reasonable science fiction stories, with eleven published so far.

My latest astronomical #sciencefiction story (my 11th) was recently published. It's a new twist on doomsday & advanced #extraterrestrials - "In Conversation with the Downloaded Me." It's at: bit.ly/downloadedme
A list of all my published stories: bit.ly/sfbyfraknoi
#astroedu #hardsf #space #scifi

11.08.2025 16:54 πŸ‘ 12 πŸ” 1 πŸ’¬ 1 πŸ“Œ 0
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ASP2025 Virtual Symposium: Eyes on the Cosmos - Embracing the Future Join us August 21, 2025 to explore the evolving relationship between humanity and the universe.

The 136-year old Astronomical Society of the Pacific is holding an exciting one-day nontechnical symposium on the future of #astronomy Aug. 21. Great speakers, time for breakout groups. See: bit.ly/ASP2025SYMP (Early bird pricing ends 7/31)
#astroedu #space #telescopes #amateurastronomy #science

29.07.2025 18:59 πŸ‘ 11 πŸ” 1 πŸ’¬ 0 πŸ“Œ 0
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ASP2025 Virtual Symposium: Eyes on the Cosmos - Embracing the Future Join us August 21, 2025 to explore the evolving relationship between humanity and the universe.

πŸš€ Register now for #ASP2025 #Virtual #Symposium: Eyes on the Cosmos -- Embracing the Future (Aug 21)!

Save with early bird registration by July 31.

Explore 4 themes: Questioning, Investigating, Adapting & Connecting.

Explore discoveries, strategies & shared sky stories. πŸ”­πŸ§ͺ

πŸ”—: bit.ly/ASP2025SYMP

23.07.2025 02:41 πŸ‘ 7 πŸ” 1 πŸ’¬ 0 πŸ“Œ 1

I agree, it does seem to be saying something like that!

24.07.2025 06:22 πŸ‘ 1 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0
The dark nebula with catalog number LDN43 resembles a flying bat.  It is a cloud of dense gas and dust inside which new stars are forming, accounting for the lighter regions that paint the features of the bat. Image credit: Mark Hanson and Mike Selby.

The dark nebula with catalog number LDN43 resembles a flying bat. It is a cloud of dense gas and dust inside which new stars are forming, accounting for the lighter regions that paint the features of the bat. Image credit: Mark Hanson and Mike Selby.

This uncanny image shows LDN43, the cosmic bat nebula -- a region of dark dust & dense gas, where new stars are forming. The nebula is 1400 lightyears away and about 12 lightyears across. #astronomy #astroedu #astrophotos #space #spacephotos #spaceimages #astrophotography #nebula #spacepictures

22.07.2025 20:53 πŸ‘ 318 πŸ” 51 πŸ’¬ 14 πŸ“Œ 5
This long time-exposure of the Gemini North Telescope dome on the 14,000 foot peak of Maunakea in Hawaii show the stars making circular trails around the north pole of the sky and the Pole Star Polaris. Some of the guide-star laser beams that help astronomers keep track of dancing of the Earth's atmosphere are also seen coming from the dome.

This long time-exposure of the Gemini North Telescope dome on the 14,000 foot peak of Maunakea in Hawaii show the stars making circular trails around the north pole of the sky and the Pole Star Polaris. Some of the guide-star laser beams that help astronomers keep track of dancing of the Earth's atmosphere are also seen coming from the dome.

Beautiful image from Gemini Observatory: the dome of their telescope on Maunkea peak, Hawaii. In this time exposure, see the stars circle the north pole of the sky as our planet rotates. Laser beams that probe atmospheric distortion add interest. #astronomy #astroedu #astrophotos #spacephotos #sky

16.07.2025 00:41 πŸ‘ 117 πŸ” 18 πŸ’¬ 3 πŸ“Œ 0
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Friday will be the #summersolstice -- the longest day and shortest night for the Northern Hemisphere. For the full story of how an ancient cosmic accident is responsible for our seasons, see: www.fraknoi.com/seasons/frid...
#astronomy #astroedu #space #science #seasons #sky #solstice

17.06.2025 17:09 πŸ‘ 9 πŸ” 4 πŸ’¬ 0 πŸ“Œ 1
The Tarantula Nebula: a composite image produced by Rob Gendler from data provided by the European Southern Observatory and the Hubble Space Telescope.  It is a star-forming nebula -- a region of gas and dust, lit up by the light of newly-born stars inside.

The Tarantula Nebula: a composite image produced by Rob Gendler from data provided by the European Southern Observatory and the Hubble Space Telescope. It is a star-forming nebula -- a region of gas and dust, lit up by the light of newly-born stars inside.

Amazing star-forming region, the Tarantula #Nebula, 160,000 lightyears away & 600 lightyears wide. Another great composite image produced by noted amateur astronomer #RobGendler. Massive, luminous baby stars help it to glow.
#astronomy #astroedu #space #spacephotos #astroimaging #sciencephotos

04.06.2025 22:26 πŸ‘ 112 πŸ” 18 πŸ’¬ 0 πŸ“Œ 1
Cartoon from an old New Yorker magazine shows two aliens in a flying saucer.  One says to the other: "I hope my address to the American Astronomical Society will bring us the credibility we've been seeking." The American Astronomical Society is the professional organization of astronomer in the U.S.

Cartoon from an old New Yorker magazine shows two aliens in a flying saucer. One says to the other: "I hope my address to the American Astronomical Society will bring us the credibility we've been seeking." The American Astronomical Society is the professional organization of astronomer in the U.S.

This coming weekend the summer meeting of the American Astronomical Society #AAS starts. If the administration's budget is passed by Congress, the science of #astronomy will be decimated in the U.S.
#astroedu #sciencefunding #UFOs #extraterrestrials #cartoons #sciencecartoons #astronomycartoons

02.06.2025 17:14 πŸ‘ 16 πŸ” 2 πŸ’¬ 0 πŸ“Œ 0
This is the illustration for my science-fiction story the Lurker.  It’s about the possibility that advanced civilizations among the stars might send automated probes to our solar system (and others); probes that wait - lurking quietly – to detect some sign of intelligent life.  I tried to imagine how some hapless explorers in the future might accidentally trigger one of these probes.

This is the illustration for my science-fiction story the Lurker. It’s about the possibility that advanced civilizations among the stars might send automated probes to our solar system (and others); probes that wait - lurking quietly – to detect some sign of intelligent life. I tried to imagine how some hapless explorers in the future might accidentally trigger one of these probes.

My latest #sciencefiction story "The Lurker" is just out in "The Worlds Within" online magazine: theworldswithin.net/the-lurker/ Just as we send probes to other planets, might advanced aliens not send AI probes to our system? Please check it out.
#astronomy #astroedu #SETI #scifi #extraterrestrials

24.05.2025 18:06 πŸ‘ 10 πŸ” 1 πŸ’¬ 0 πŸ“Œ 0
Eclipse sequence, showing how a total eclipse of the Sun happens, by Rick Fienberg (astronomer, astro-photographer, and veteran eclipse chaser.)  Here the Moon exactly covers the Sun, blotting out its entire body, and allowing its faint atmosphere to become visible.

Eclipse sequence, showing how a total eclipse of the Sun happens, by Rick Fienberg (astronomer, astro-photographer, and veteran eclipse chaser.) Here the Moon exactly covers the Sun, blotting out its entire body, and allowing its faint atmosphere to become visible.

My latest (short) science-fiction story "Eclipsed" was published today. It's about how rare total eclipses might be, not just in the solar system, but the universe. See: bit.ly/eclipsedsfst...
#astronomy #astroedu #scifi #sciencefiction #hardsf #hardsciencefiction #eclipses #eclipsechasing

20.05.2025 02:08 πŸ‘ 17 πŸ” 4 πŸ’¬ 1 πŸ“Œ 0
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For those who enjoy #StarTrek and fine art, this is a T-shirt you can buy. (I am not involved with the company, just amused.)

#astronomy #astroedu #sciencefiction #art #scifi #VanGogh #sciencehumor #astroart #scienceandart

15.05.2025 18:05 πŸ‘ 32 πŸ” 3 πŸ’¬ 2 πŸ“Œ 1
This colorful region of glowing gas, often called the Veil Nebula, is part of the large, old supernova remnant called the Cygnus Loop.  A massive star exploded some 10-20 thousand years ago and the remnant is still glowing in places.  Astronomers have determined that  oxygen, sulfur, and hydrogen atoms are contributing to the glow.

This colorful region of glowing gas, often called the Veil Nebula, is part of the large, old supernova remnant called the Cygnus Loop. A massive star exploded some 10-20 thousand years ago and the remnant is still glowing in places. Astronomers have determined that oxygen, sulfur, and hydrogen atoms are contributing to the glow.

We see the Veil Nebula, a small part of a vast ancient remnant of an exploded star, still glowing with colorful emissions from hydrogen, oxygen, and sulfur atoms.
#astronomy #astroedu #astrophotography #space #spaceimages #spacephotos #astroimages #NASA #sciencephotos

13.05.2025 23:14 πŸ‘ 63 πŸ” 11 πŸ’¬ 2 πŸ“Œ 3

She was born in England, but seeing no chance to get a PhD there, moved to the U.S., where she stayed.

11.05.2025 05:20 πŸ‘ 2 πŸ” 0 πŸ’¬ 1 πŸ“Œ 0
Cecilia Payne, born in England, got her PhD in the U.S., showing the then controversial result that the vast majority of each star is composed of the simplest elements hydrogen and helium.  This contradicted the widely held notion that the Sun and the Earth should have roughly the same composition.  As a woman, she was not allowed to hold a professorship at Harvard for many year during her long career there.

Cecilia Payne, born in England, got her PhD in the U.S., showing the then controversial result that the vast majority of each star is composed of the simplest elements hydrogen and helium. This contradicted the widely held notion that the Sun and the Earth should have roughly the same composition. As a woman, she was not allowed to hold a professorship at Harvard for many year during her long career there.

Today is the birthday (in 1900) of Cecilia Payne, the astronomer who wrote what some historians call the most important PhD thesis in astronomy -- showing that stars were made mostly of hydrogen and helium.
#astronomy #astroedu #astronomyhistory #historyofscience #womenastronomers #womeninscience

10.05.2025 18:23 πŸ‘ 45 πŸ” 15 πŸ’¬ 2 πŸ“Œ 0

I meant to type @debrafischer.bsky.social in the message, not #debrafischer (Still getting used to how BlueSky works.

05.05.2025 20:18 πŸ‘ 1 πŸ” 0 πŸ’¬ 2 πŸ“Œ 0
Support U.S. Science!
Support U.S. Science! YouTube video by Astronomers for Planet Earth

#Astro4Earth and #debrafischer just posted a 1-min public video: huge cuts in proposed US budget for #NSF and #NASA & about the beauty and value of astronomy, at: www.youtube.com/watch?v=jZsQ... Please share if you resonate with it.
#astronomy #astroedu #space #science #sciencebudget #budgetcuts

05.05.2025 20:15 πŸ‘ 19 πŸ” 5 πŸ’¬ 1 πŸ“Œ 1
WR8, a Wolf-Rayet Star. These are massive stars losing their outer layers forcefully toward the end of their lives. The blue is the ejected material, the reddish glow comes from glowing gas and dust lying behind or front of the star, but not connected with it.

WR8, a Wolf-Rayet Star. These are massive stars losing their outer layers forcefully toward the end of their lives. The blue is the ejected material, the reddish glow comes from glowing gas and dust lying behind or front of the star, but not connected with it.

Beautiful image by Robert Fesen & collaborators showing a Wolf-Rayet star (WR8) -- a massive star violently letting go its outer layer (blue) against a background of glowing gas.
#astronomy #astroedu #astrophotography #space #spacephotography #astroimages #sciencephotos #spacephotos #astrophotos

02.05.2025 17:23 πŸ‘ 90 πŸ” 13 πŸ’¬ 0 πŸ“Œ 0
The Ring Nebula, a "planetary" nebula (misnomer), probably better called a death-shroud nebula.  This material, shown in a photo that combines visible-light and infrared images, is emitted in several steps from a dying star, in the process of becoming a dense white dwarf. The hot star excites that material that "lifted off" and makes it glow.

The Ring Nebula, a "planetary" nebula (misnomer), probably better called a death-shroud nebula. This material, shown in a photo that combines visible-light and infrared images, is emitted in several steps from a dying star, in the process of becoming a dense white dwarf. The hot star excites that material that "lifted off" and makes it glow.

Complex, beautiful image, assembled by Rob Gendler, from several visible-light & Infrared telescopes, shows the Ring Nebula, with its many shells of material emitted by a dying star.
#astronomy #astroedu #space #spacephotos #astroimaging #stars #sciencephotos #astrophotography #spaceimages

01.05.2025 00:20 πŸ‘ 172 πŸ” 40 πŸ’¬ 6 πŸ“Œ 2

YES. Why didn't I think of that?

25.04.2025 06:43 πŸ‘ 4 πŸ” 0 πŸ’¬ 1 πŸ“Œ 0
Planetary nebula NGC 2899 glows from the energy of the hot white dwarf star in the center.  The cavity in the expelled gas resembles the shape of a moth.  The shape may be the result of the fact that the dying star that gave rise to the nebula orbits around a companion star in the center.  The whole nebula is more than 2 lightyears across.

Planetary nebula NGC 2899 glows from the energy of the hot white dwarf star in the center. The cavity in the expelled gas resembles the shape of a moth. The shape may be the result of the fact that the dying star that gave rise to the nebula orbits around a companion star in the center. The whole nebula is more than 2 lightyears across.

Beautiful new #HubbleTelescope image of the "death-shroud nebula" with catalog designation #NGC2899. The central star is giving off its outer layers in dying. What does the cavity in the gas look like to you?
#astronomy #astroedu #space #spacephotos #astroimaging #astronomyphotos #sciencephotos

24.04.2025 19:42 πŸ‘ 97 πŸ” 22 πŸ’¬ 5 πŸ“Œ 0
Sign in the window of a book store indicating that stories about what it's like after the apocalypse have been moved to "current affairs."

Sign in the window of a book store indicating that stories about what it's like after the apocalypse have been moved to "current affairs."

Sign in a bookstore window, appropriate for the day after Earth Day. (Now that I am a published science-fiction writer, I pay special attention to such signs.)
#climatechange #science #sciencehumor #apocalypse #globalwarming #sciencefiction #bookstores

23.04.2025 19:59 πŸ‘ 9 πŸ” 2 πŸ’¬ 1 πŸ“Œ 0
Listing of the meteor showers of 2025. ZHR tell you how many meteors you might see under IDEAL conditions.  The star ratings are based on whether moonlight is likely to interfere with your viewing faint meteors.

Listing of the meteor showers of 2025. ZHR tell you how many meteors you might see under IDEAL conditions. The star ratings are based on whether moonlight is likely to interfere with your viewing faint meteors.

Tonight and tomorrow night are peak times to see the #Lyrids #meteorshower -- a time when more shooting stars are visible if you go to a dark, open site and are patient. The chart shows you the main showers of 2025 and rates them.
#astronomy #astroedu #sky #amateurastronomy #darksky #space #meteors

21.04.2025 18:57 πŸ‘ 8 πŸ” 2 πŸ’¬ 0 πŸ“Œ 0

I agree. We live in a wondrous universe.

21.04.2025 02:24 πŸ‘ 0 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0