David S. F. Portree
@dsfpspacefl1ght.bsky.social
history guy, science writer, educator, map librarian, archivist, 57 yrs a space exploration nut, ex-NASA, ex-US Geological Survey, now doing local history among the pines in Flagstaff AZ USA
Save NASA space science
https://spaceflighthistory.blogspot.com
Save NASA space science
https://spaceflighthistory.blogspot.com
Pinned
I realized that the minimum-energy crewed Mars mission post is the denouement of the crewed flyby planning story I've dug into these past 30 yrs. If I were to plug it into a new edition of my HUMANS TO MARS book, it would conclude what is in the 2001 edition chapter 4.
ntrs.nasa.gov/citations/20...
ntrs.nasa.gov/citations/20...
Reposted by David S. F. Portree
We love rock-et roll 🤘🚀
Last week, NASA's Artemis II rocket rolled to its launchpad.
At the top, Orion and @esa.int's European Service Module are ready to carry four astronauts on this historic Moon mission 🌙👨🚀
Last week, NASA's Artemis II rocket rolled to its launchpad.
At the top, Orion and @esa.int's European Service Module are ready to carry four astronauts on this historic Moon mission 🌙👨🚀
January 26, 2026 at 11:33 AM
We love rock-et roll 🤘🚀
Last week, NASA's Artemis II rocket rolled to its launchpad.
At the top, Orion and @esa.int's European Service Module are ready to carry four astronauts on this historic Moon mission 🌙👨🚀
Last week, NASA's Artemis II rocket rolled to its launchpad.
At the top, Orion and @esa.int's European Service Module are ready to carry four astronauts on this historic Moon mission 🌙👨🚀
Reposted by David S. F. Portree
The crew entered quarantine on Jan 23, and the SLS rocket is at Pad 39B. Can't wait to see humans orbit the Moon again! 🚀
Www.contactlight.de
Www.forallmankind.de
Www.contactlight.de
Www.forallmankind.de
January 26, 2026 at 1:02 PM
The crew entered quarantine on Jan 23, and the SLS rocket is at Pad 39B. Can't wait to see humans orbit the Moon again! 🚀
Www.contactlight.de
Www.forallmankind.de
Www.contactlight.de
Www.forallmankind.de
Reposted by David S. F. Portree
January 25, 2026 at 10:39 PM
Reposted by David S. F. Portree
1968: Lovell, Anders & Borman become the first to orbit the Moon and show humanity the “Earthrise.”
2026: Wiseman, Glover, Koch & Hansen follow their path with Artemis II.
Same Moon. New generation. Same courage. 🌕🚀
Www.contactlight.de
Www.forallmankind.de
2026: Wiseman, Glover, Koch & Hansen follow their path with Artemis II.
Same Moon. New generation. Same courage. 🌕🚀
Www.contactlight.de
Www.forallmankind.de
January 26, 2026 at 1:22 PM
1968: Lovell, Anders & Borman become the first to orbit the Moon and show humanity the “Earthrise.”
2026: Wiseman, Glover, Koch & Hansen follow their path with Artemis II.
Same Moon. New generation. Same courage. 🌕🚀
Www.contactlight.de
Www.forallmankind.de
2026: Wiseman, Glover, Koch & Hansen follow their path with Artemis II.
Same Moon. New generation. Same courage. 🌕🚀
Www.contactlight.de
Www.forallmankind.de
Reposted by David S. F. Portree
HiPOD: Wind Carved Rock
The distinctively fluted surface and elongated hills in this image in Medusae Fossae are caused by wind erosion of a soft fine-grained rock. Called yardangs, these features are aligned with the prevailing wind direction.
https://uahirise.org/hipod/ESP_046504_1785
#Mars
The distinctively fluted surface and elongated hills in this image in Medusae Fossae are caused by wind erosion of a soft fine-grained rock. Called yardangs, these features are aligned with the prevailing wind direction.
https://uahirise.org/hipod/ESP_046504_1785
#Mars
January 25, 2026 at 3:00 PM
HiPOD: Wind Carved Rock
The distinctively fluted surface and elongated hills in this image in Medusae Fossae are caused by wind erosion of a soft fine-grained rock. Called yardangs, these features are aligned with the prevailing wind direction.
https://uahirise.org/hipod/ESP_046504_1785
#Mars
The distinctively fluted surface and elongated hills in this image in Medusae Fossae are caused by wind erosion of a soft fine-grained rock. Called yardangs, these features are aligned with the prevailing wind direction.
https://uahirise.org/hipod/ESP_046504_1785
#Mars
Reposted by David S. F. Portree
Hallo zusammen - wie gewohnt mit einem aktuellen Bild der Sonne per Satellit GOES-19. Credit: NOAA
January 26, 2026 at 9:29 AM
Hallo zusammen - wie gewohnt mit einem aktuellen Bild der Sonne per Satellit GOES-19. Credit: NOAA
Reposted by David S. F. Portree
Chuck has finally read the room
January 25, 2026 at 12:03 AM
Chuck has finally read the room
Reposted by David S. F. Portree
LA doesn’t miss 🔥
Freeway overpass just now (405)
Freeway overpass just now (405)
January 25, 2026 at 12:03 AM
LA doesn’t miss 🔥
Freeway overpass just now (405)
Freeway overpass just now (405)
Reposted by David S. F. Portree
INBOX: Schumer announces Senate Democrats Will Not Advance Appropriations Bill If DHS Funding Is Included.
"Senate Democrats will not provide the votes to proceed to the appropriations bill if the DHS funding bill is included"
"Senate Democrats will not provide the votes to proceed to the appropriations bill if the DHS funding bill is included"
January 24, 2026 at 11:54 PM
INBOX: Schumer announces Senate Democrats Will Not Advance Appropriations Bill If DHS Funding Is Included.
"Senate Democrats will not provide the votes to proceed to the appropriations bill if the DHS funding bill is included"
"Senate Democrats will not provide the votes to proceed to the appropriations bill if the DHS funding bill is included"
Reposted by David S. F. Portree
Reposted by David S. F. Portree
Not one more cent for DHS and ICE. We have the power to end this.
January 24, 2026 at 10:51 PM
Not one more cent for DHS and ICE. We have the power to end this.
Reposted by David S. F. Portree
None of this even starts to get better until our news media starts acknowledging, in print and on TV, the simple objective fact, with video evidence to prove it, that the secretary of Homeland security flat out lied about what happened. There isn’t a “dispute” or “controversy.” She just lied.
January 24, 2026 at 11:21 PM
None of this even starts to get better until our news media starts acknowledging, in print and on TV, the simple objective fact, with video evidence to prove it, that the secretary of Homeland security flat out lied about what happened. There isn’t a “dispute” or “controversy.” She just lied.
Reposted by David S. F. Portree
Today in 1986, Voyager 2 made humanity's first and only encounter with Uranus, revealing its clouds, rings, and fascinating zoo of moons.
January 24, 2026 at 5:18 PM
Today in 1986, Voyager 2 made humanity's first and only encounter with Uranus, revealing its clouds, rings, and fascinating zoo of moons.
Reposted by David S. F. Portree
The Trump-Vance administration just used your taxes to pay for ICE agents to kill a 37-year-old nurse, who was only there because another ICE agent killed a 37-year-old mother of three, who was only there because ICE agents are kidnapping your neighbors
January 24, 2026 at 7:43 PM
The Trump-Vance administration just used your taxes to pay for ICE agents to kill a 37-year-old nurse, who was only there because another ICE agent killed a 37-year-old mother of three, who was only there because ICE agents are kidnapping your neighbors
Reposted by David S. F. Portree
The Nazi SA - Sturmabteilung, or Storm Troopers - were often recruited from the dregs of society: barely literate failures incapable of holding down a job and only fit for murder and terror. The scum of Germany. Hitler gave them free rein to vent their rage on their betters. Sound familiar, America?
January 24, 2026 at 5:42 PM
The Nazi SA - Sturmabteilung, or Storm Troopers - were often recruited from the dregs of society: barely literate failures incapable of holding down a job and only fit for murder and terror. The scum of Germany. Hitler gave them free rein to vent their rage on their betters. Sound familiar, America?
Reposted by David S. F. Portree
If only you were in a position of power to exercise some kind of leverage against the administration to make this happen.
ICE out of Minnesota NOW.
Breaking News: Federal law enforcement agents shot and killed a person in Minneapolis on Saturday morning, state and local officials said. Follow live updates.
January 24, 2026 at 8:52 PM
If only you were in a position of power to exercise some kind of leverage against the administration to make this happen.
Reposted by David S. F. Portree
shouting for the journalists in the back: IT’S NOT AN IMMIGRATION CRACKDOWN.
It’s a federal occupation of a city that didnt vote the right way. And the occupying force is there to enforce civil infractions, misdemeanors.
It’s a federal occupation of a city that didnt vote the right way. And the occupying force is there to enforce civil infractions, misdemeanors.
January 24, 2026 at 10:49 PM
shouting for the journalists in the back: IT’S NOT AN IMMIGRATION CRACKDOWN.
It’s a federal occupation of a city that didnt vote the right way. And the occupying force is there to enforce civil infractions, misdemeanors.
It’s a federal occupation of a city that didnt vote the right way. And the occupying force is there to enforce civil infractions, misdemeanors.
Reposted by David S. F. Portree
AOC: "This really isn't just about Democrats. This is about Democrats, Republicans, and independents. There has been this permission structure where we have all universally accepted that the GOP will simply just have no morals, or fall in line, and we have to challenge that logic and rhetoric."
January 24, 2026 at 10:57 PM
AOC: "This really isn't just about Democrats. This is about Democrats, Republicans, and independents. There has been this permission structure where we have all universally accepted that the GOP will simply just have no morals, or fall in line, and we have to challenge that logic and rhetoric."
Reposted by David S. F. Portree
If you're living somewhere outside the USA, one thing you can do is pressure your leaders to boycott World Cup and Olympic events here.
January 24, 2026 at 8:29 PM
If you're living somewhere outside the USA, one thing you can do is pressure your leaders to boycott World Cup and Olympic events here.
Reposted by David S. F. Portree
Titan bulb - From Val Klavans (valklavans.bsky.social) - https://flic.kr/p/cEoUyh
January 24, 2026 at 11:00 PM
Titan bulb - From Val Klavans (valklavans.bsky.social) - https://flic.kr/p/cEoUyh
Reposted by David S. F. Portree
gearing up now. fountains growing, massive amounts of lava flowing out.
not trying to distract you from events, but if you feel you need a break the earth is re-creating itself in spectacular fashion on live camera.
not trying to distract you from events, but if you feel you need a break the earth is re-creating itself in spectacular fashion on live camera.
kīlauea is doing things again. not fountaining (yet), but this was how the last really good episode started and that turned into massive (800ft) lava fountains
www.youtube.com/live/gXKuUyK...
www.youtube.com/live/gXKuUyK...
[V3cam] Kīlauea volcano, Hawaii (south Halemaʻumaʻu crater)
YouTube video by USGS
www.youtube.com
January 24, 2026 at 9:29 PM
gearing up now. fountains growing, massive amounts of lava flowing out.
not trying to distract you from events, but if you feel you need a break the earth is re-creating itself in spectacular fashion on live camera.
not trying to distract you from events, but if you feel you need a break the earth is re-creating itself in spectacular fashion on live camera.
Reposted by David S. F. Portree
Big Bear bald eagles Jackie and Shadow welcome first egg of 2026
Big Bear bald eagles Jackie and Shadow welcome first egg of 2026
Jackie and Shadow, the much-adored Big Bear-based bald eagle couple whose nest is watched by countless observers across the world, welcomed their first egg of 2026 on Friday! Friends of Big Bear V…
ktla.com
January 24, 2026 at 5:00 PM
Big Bear bald eagles Jackie and Shadow welcome first egg of 2026
Reposted by David S. F. Portree
👁️👁️
AOC on Noem's lies: "They are asking you to give up your belief in your own senses and instead hand over your belief to anything they say ... look at it for yourself and what you will see is an innocent man being executed in the street."
January 24, 2026 at 11:03 PM
👁️👁️
Reposted by David S. F. Portree
Why do we have to go through all this so one man can stay out of prison?
January 24, 2026 at 7:17 PM
Why do we have to go through all this so one man can stay out of prison?