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
The NASA Manned Spacecraft Center minimum-energy crewed Mars mission study (1968-69) post is coming along well. I got bogged down in the math for a while, until I realized that nearly all of it is approximations. They lacked data sufficient to know what would really work.
Now I am free and writing.
Now I am free and writing.
Reposted by David S. F. Portree
HiPOD: Ejecta Moving into Crater in Chryse Planitia
The objective of this observation is to examine what appears to be ejecta moving into a small crater. More resolution is needed to tell exactly what is going on here.
https://uahirise.org/hipod/ESP_076514_2070
#Mars #science #NASA
The objective of this observation is to examine what appears to be ejecta moving into a small crater. More resolution is needed to tell exactly what is going on here.
https://uahirise.org/hipod/ESP_076514_2070
#Mars #science #NASA
December 9, 2025 at 3:01 PM
HiPOD: Ejecta Moving into Crater in Chryse Planitia
The objective of this observation is to examine what appears to be ejecta moving into a small crater. More resolution is needed to tell exactly what is going on here.
https://uahirise.org/hipod/ESP_076514_2070
#Mars #science #NASA
The objective of this observation is to examine what appears to be ejecta moving into a small crater. More resolution is needed to tell exactly what is going on here.
https://uahirise.org/hipod/ESP_076514_2070
#Mars #science #NASA
Reposted by David S. F. Portree
From NASA: A new NASA study shows that the Sun has been waking up from a period of low activity. ☀️
Scientists track solar activity because it can affect spacecraft, astronaut safety, radio communications, GPS, and even power grids on Earth. go.nasa.gov/4gnZQyc
Scientists track solar activity because it can affect spacecraft, astronaut safety, radio communications, GPS, and even power grids on Earth. go.nasa.gov/4gnZQyc
NASA Analysis Shows Sun’s Activity Ramping Up
It looked like the Sun was heading toward a historic lull in activity. That trend flipped in 2008, according to new research.
go.nasa.gov
December 8, 2025 at 5:37 PM
From NASA: A new NASA study shows that the Sun has been waking up from a period of low activity. ☀️
Scientists track solar activity because it can affect spacecraft, astronaut safety, radio communications, GPS, and even power grids on Earth. go.nasa.gov/4gnZQyc
Scientists track solar activity because it can affect spacecraft, astronaut safety, radio communications, GPS, and even power grids on Earth. go.nasa.gov/4gnZQyc
Reposted by David S. F. Portree
Hubble image of Arp 184, also known as NGC 1961.
NGC 1961 is an extremely massive spiral galaxy. Its near side has a large spiral arm dotted with blue star clusters. Its far side lacks a similarly impressive arm.
Credit: ESA, NASA, J. Dalcanton, R. J. Foley, C. Kilpatrick
Source
NGC 1961 is an extremely massive spiral galaxy. Its near side has a large spiral arm dotted with blue star clusters. Its far side lacks a similarly impressive arm.
Credit: ESA, NASA, J. Dalcanton, R. J. Foley, C. Kilpatrick
Source
December 9, 2025 at 12:31 AM
Hubble image of Arp 184, also known as NGC 1961.
NGC 1961 is an extremely massive spiral galaxy. Its near side has a large spiral arm dotted with blue star clusters. Its far side lacks a similarly impressive arm.
Credit: ESA, NASA, J. Dalcanton, R. J. Foley, C. Kilpatrick
Source
NGC 1961 is an extremely massive spiral galaxy. Its near side has a large spiral arm dotted with blue star clusters. Its far side lacks a similarly impressive arm.
Credit: ESA, NASA, J. Dalcanton, R. J. Foley, C. Kilpatrick
Source
Reposted by David S. F. Portree
😻😻😻HAPPY BADGER NOISES!
CLEANSING THERMONUCLEAR FIRE IS CANCELED FOR THE EVENING!😻😻😻
CLEANSING THERMONUCLEAR FIRE IS CANCELED FOR THE EVENING!😻😻😻
December 8, 2025 at 5:19 AM
😻😻😻HAPPY BADGER NOISES!
CLEANSING THERMONUCLEAR FIRE IS CANCELED FOR THE EVENING!😻😻😻
CLEANSING THERMONUCLEAR FIRE IS CANCELED FOR THE EVENING!😻😻😻
Reposted by David S. F. Portree
Accountability for ICE is not a prediction....
It's a PROMISE.
It's a PROMISE.
December 8, 2025 at 8:52 PM
Accountability for ICE is not a prediction....
It's a PROMISE.
It's a PROMISE.
Reposted by David S. F. Portree
Some gorgeous new images came back from Curiosity on Mars... Just going to have to post these because I don't have the geology knowledge to describe what we're seeing here, or the right words to describe just how beautiful this landscape is... NASA/JPL-Caltech/MSSS/fredk/S Atkinson
December 8, 2025 at 9:07 PM
Some gorgeous new images came back from Curiosity on Mars... Just going to have to post these because I don't have the geology knowledge to describe what we're seeing here, or the right words to describe just how beautiful this landscape is... NASA/JPL-Caltech/MSSS/fredk/S Atkinson
Reposted by David S. F. Portree
There are FOUR CMEs that could impact Earth in the next few days!
M1.1 from AR 4299: 2025-12-10 8 UT (grazing impact)
M8.1 from AR 4299: 2025-12-09 5 UT (direct hit)
M2.4 from AR 4299: 2025-12-10 13 UT (direct hit)
X1.1 from AR 4298: Dec 11 at 10 UT (grazing impact)
M1.1 from AR 4299: 2025-12-10 8 UT (grazing impact)
M8.1 from AR 4299: 2025-12-09 5 UT (direct hit)
M2.4 from AR 4299: 2025-12-10 13 UT (direct hit)
X1.1 from AR 4298: Dec 11 at 10 UT (grazing impact)
December 8, 2025 at 6:06 PM
There are FOUR CMEs that could impact Earth in the next few days!
M1.1 from AR 4299: 2025-12-10 8 UT (grazing impact)
M8.1 from AR 4299: 2025-12-09 5 UT (direct hit)
M2.4 from AR 4299: 2025-12-10 13 UT (direct hit)
X1.1 from AR 4298: Dec 11 at 10 UT (grazing impact)
M1.1 from AR 4299: 2025-12-10 8 UT (grazing impact)
M8.1 from AR 4299: 2025-12-09 5 UT (direct hit)
M2.4 from AR 4299: 2025-12-10 13 UT (direct hit)
X1.1 from AR 4298: Dec 11 at 10 UT (grazing impact)
Reposted by David S. F. Portree
🔊 #NowPlaying on #BBCRadio3:
#ThroughTheNight
- Rachmaninov and Mahler at the 2023 BBC Proms
The BBC Philharmonic with Stephen Hough performing Rachmaninov's piano concerto no 1.
▶️ Relisten on BBCSounds
#ThroughTheNight
- Rachmaninov and Mahler at the 2023 BBC Proms
The BBC Philharmonic with Stephen Hough performing Rachmaninov's piano concerto no 1.
▶️ Relisten on BBCSounds
BBC Radio 3 - Through the Night, Rachmaninov and Mahler at the 2023 BBC Proms
The BBC Philharmonic with Stephen Hough performing Rachmaninov's piano concerto no 1.
www.bbc.co.uk
December 9, 2025 at 12:30 AM
🔊 #NowPlaying on #BBCRadio3:
#ThroughTheNight
- Rachmaninov and Mahler at the 2023 BBC Proms
The BBC Philharmonic with Stephen Hough performing Rachmaninov's piano concerto no 1.
▶️ Relisten on BBCSounds
#ThroughTheNight
- Rachmaninov and Mahler at the 2023 BBC Proms
The BBC Philharmonic with Stephen Hough performing Rachmaninov's piano concerto no 1.
▶️ Relisten on BBCSounds
Reposted by David S. F. Portree
🤖 A robot in the Netherlands controlled from the UK.
@esa.int's human-robot interactions team linked engineers at its ECSAT 🇬🇧 site to a robotic arm at ESTEC 🇳🇱.
🔗 www.esa.int/Space_in_Mem...
@esa.int's human-robot interactions team linked engineers at its ECSAT 🇬🇧 site to a robotic arm at ESTEC 🇳🇱.
🔗 www.esa.int/Space_in_Mem...
December 8, 2025 at 2:21 PM
🤖 A robot in the Netherlands controlled from the UK.
@esa.int's human-robot interactions team linked engineers at its ECSAT 🇬🇧 site to a robotic arm at ESTEC 🇳🇱.
🔗 www.esa.int/Space_in_Mem...
@esa.int's human-robot interactions team linked engineers at its ECSAT 🇬🇧 site to a robotic arm at ESTEC 🇳🇱.
🔗 www.esa.int/Space_in_Mem...
Reposted by David S. F. Portree
📡 Separated by the North Sea, connected by satellite.
🕹️ Engineers used the team's custom controller to move the robotic arm and grab samples.
🌕 Future Moon missions could use the same tech to explore safely from afar.
🕹️ Engineers used the team's custom controller to move the robotic arm and grab samples.
🌕 Future Moon missions could use the same tech to explore safely from afar.
December 8, 2025 at 2:22 PM
📡 Separated by the North Sea, connected by satellite.
🕹️ Engineers used the team's custom controller to move the robotic arm and grab samples.
🌕 Future Moon missions could use the same tech to explore safely from afar.
🕹️ Engineers used the team's custom controller to move the robotic arm and grab samples.
🌕 Future Moon missions could use the same tech to explore safely from afar.
Reposted by David S. F. Portree
🌌 Our human-robot interaction team is no stranger to long distances.
🛰️ This summer, NASA astronaut Jonny Kim operated @esa.int and @dlr-en.bsky.social robots from the International Space Station.
🔗 www.esa.int/ESA_Multimed...
🛰️ This summer, NASA astronaut Jonny Kim operated @esa.int and @dlr-en.bsky.social robots from the International Space Station.
🔗 www.esa.int/ESA_Multimed...
December 8, 2025 at 2:23 PM
🌌 Our human-robot interaction team is no stranger to long distances.
🛰️ This summer, NASA astronaut Jonny Kim operated @esa.int and @dlr-en.bsky.social robots from the International Space Station.
🔗 www.esa.int/ESA_Multimed...
🛰️ This summer, NASA astronaut Jonny Kim operated @esa.int and @dlr-en.bsky.social robots from the International Space Station.
🔗 www.esa.int/ESA_Multimed...
Reposted by David S. F. Portree
HiRISE 3D: Crater Exposing Layers in Icy Deposits
This crater intersects a viscous flow feature and later an ice-rich mantling deposit. The crater walls host unusually clear layering structures.
https://www.uahirise.org/anaglyph/ESP_090128_2175_ESP_089851_2175_RED
#Mars #NASA #science
This crater intersects a viscous flow feature and later an ice-rich mantling deposit. The crater walls host unusually clear layering structures.
https://www.uahirise.org/anaglyph/ESP_090128_2175_ESP_089851_2175_RED
#Mars #NASA #science
December 8, 2025 at 10:00 PM
HiRISE 3D: Crater Exposing Layers in Icy Deposits
This crater intersects a viscous flow feature and later an ice-rich mantling deposit. The crater walls host unusually clear layering structures.
https://www.uahirise.org/anaglyph/ESP_090128_2175_ESP_089851_2175_RED
#Mars #NASA #science
This crater intersects a viscous flow feature and later an ice-rich mantling deposit. The crater walls host unusually clear layering structures.
https://www.uahirise.org/anaglyph/ESP_090128_2175_ESP_089851_2175_RED
#Mars #NASA #science
Reposted by David S. F. Portree
HiPOD: Layering in Western Arabia Terra
This image provides a look at layered deposits that with a stereo pair with maximal vertical resolution, can give us some insight into bed thickness measurements.
https://uahirise.org/hipod/ESP_076447_1900
NASA/JPL-Caltech/University of Arizona
#Mars
This image provides a look at layered deposits that with a stereo pair with maximal vertical resolution, can give us some insight into bed thickness measurements.
https://uahirise.org/hipod/ESP_076447_1900
NASA/JPL-Caltech/University of Arizona
#Mars
December 8, 2025 at 7:01 PM
HiPOD: Layering in Western Arabia Terra
This image provides a look at layered deposits that with a stereo pair with maximal vertical resolution, can give us some insight into bed thickness measurements.
https://uahirise.org/hipod/ESP_076447_1900
NASA/JPL-Caltech/University of Arizona
#Mars
This image provides a look at layered deposits that with a stereo pair with maximal vertical resolution, can give us some insight into bed thickness measurements.
https://uahirise.org/hipod/ESP_076447_1900
NASA/JPL-Caltech/University of Arizona
#Mars
Reposted by David S. F. Portree
The Sun is firing on all cylinders as we now have an M1.84 flare peaking now from AR 4299. This region is in a good position to produce CMEs which could affect Earth. Let's see if it launched one with this latest event...
December 8, 2025 at 7:10 AM
The Sun is firing on all cylinders as we now have an M1.84 flare peaking now from AR 4299. This region is in a good position to produce CMEs which could affect Earth. Let's see if it launched one with this latest event...
Reposted by David S. F. Portree
Another unexpected major-flare player AR 4298 just fired off an impulsive X1.14 flare!
December 8, 2025 at 5:08 AM
Another unexpected major-flare player AR 4298 just fired off an impulsive X1.14 flare!
Reposted by David S. F. Portree
Difference imagery of the recent M2.4 and M2.0 flares. The CME associated with the M2.4 flare is pretty weak, unfortunately, but we'll see what the signature in coronagraphs look like. That will give us a better idea...
December 8, 2025 at 1:56 AM
Difference imagery of the recent M2.4 and M2.0 flares. The CME associated with the M2.4 flare is pretty weak, unfortunately, but we'll see what the signature in coronagraphs look like. That will give us a better idea...
Reposted by David S. F. Portree
who could have predicted that China would not hold up its end of the bargain? I mean, me, in print, and also anyone else with a working brain, but nevertheless.
1) Impose massive tariffs on China
2) China retaliates by ending its soybean imports
3) Cut deal w/ China so they'll buy our soybeans
4) China buys only 20%, so far, of what it agreed to purchase
5) Offer $12 billion to US farmers so they don't go bankrupt
www.wsj.com/politics/pol...
2) China retaliates by ending its soybean imports
3) Cut deal w/ China so they'll buy our soybeans
4) China buys only 20%, so far, of what it agreed to purchase
5) Offer $12 billion to US farmers so they don't go bankrupt
www.wsj.com/politics/pol...
Trump to Unveil $12 Billion Bailout for Farmers
The financial aid comes as the agriculture sector grapples with the fallout from the president’s tariffs.
www.wsj.com
December 8, 2025 at 3:00 PM
who could have predicted that China would not hold up its end of the bargain? I mean, me, in print, and also anyone else with a working brain, but nevertheless.
Reposted by David S. F. Portree
Like, follow, share to help support libraries!
December 8, 2025 at 3:02 PM
Like, follow, share to help support libraries!
Reposted by David S. F. Portree
Guten Morgen zusammen - wie gewohnt mit einem aktuellen Bild der Sonne per Satellit GOES-19. Credit: NOAA
December 8, 2025 at 5:21 AM
Guten Morgen zusammen - wie gewohnt mit einem aktuellen Bild der Sonne per Satellit GOES-19. Credit: NOAA
Reposted by David S. F. Portree
Nachtrag: Wie im ALT-Text erwähnt und gut zu erkennen, hat unser morgendliches Sonnenbild zufällig den Moment erwischt, als es in der ansonsten ruhigen Sonnenflecken-Region kurz aufgeblitzt hat. Hier dazu das Zeitraffer-Video der letzten Stunden: www.star.nesdis.noaa.gov/goes/SUVI_ba...
GOES-19 Solar Ultraviolet Imager (SUVI) - Fe131 Å - NOAA / NESDIS / STAR
Near real-time publication of GOES-East and GOES-West images from NOAA/NESDIS/STAR
www.star.nesdis.noaa.gov
December 8, 2025 at 5:32 AM
Nachtrag: Wie im ALT-Text erwähnt und gut zu erkennen, hat unser morgendliches Sonnenbild zufällig den Moment erwischt, als es in der ansonsten ruhigen Sonnenflecken-Region kurz aufgeblitzt hat. Hier dazu das Zeitraffer-Video der letzten Stunden: www.star.nesdis.noaa.gov/goes/SUVI_ba...
Reposted by David S. F. Portree
Perseverance landing Feb. 18, 2021 - From Simeon Schmauß (stim3on.bsky.social) - https://flic.kr/p/2qzpFQN
December 8, 2025 at 3:00 AM
Perseverance landing Feb. 18, 2021 - From Simeon Schmauß (stim3on.bsky.social) - https://flic.kr/p/2qzpFQN
Reposted by David S. F. Portree
Boom-boom! Two flares fire in quick succession now from AR 4299 (M2.4) and AR 4294 (M2.0). For AR 4294, this is its first M-flare in days as it nears the western limb. AR 4299 fired a CME with a likely Earth-directed component as it sits in the Earth-strike zone now.
December 8, 2025 at 12:56 AM
Boom-boom! Two flares fire in quick succession now from AR 4299 (M2.4) and AR 4294 (M2.0). For AR 4294, this is its first M-flare in days as it nears the western limb. AR 4299 fired a CME with a likely Earth-directed component as it sits in the Earth-strike zone now.
Reposted by David S. F. Portree
Just now: M2.4 + M2 solar flares from AR 4299 and AR 4294, respectively. There is a CME associated with the former that looks to have a substantial Earth-directed component! Great news for aurora chasers to mark a potentially THIRD Earth-directed CME hitting this week.
December 8, 2025 at 12:50 AM
Just now: M2.4 + M2 solar flares from AR 4299 and AR 4294, respectively. There is a CME associated with the former that looks to have a substantial Earth-directed component! Great news for aurora chasers to mark a potentially THIRD Earth-directed CME hitting this week.
Reposted by David S. F. Portree
For a top-level overview of what is happening, here is the official G3-watch bulletin from NOAA SWPC. Agencies are forecasting the CME to arrive early on Tuesday UT day, i.e., Monday night. CMEs can cause large geomagnetic storms, and there is a large CME headed towards us now.
December 7, 2025 at 7:53 PM
For a top-level overview of what is happening, here is the official G3-watch bulletin from NOAA SWPC. Agencies are forecasting the CME to arrive early on Tuesday UT day, i.e., Monday night. CMEs can cause large geomagnetic storms, and there is a large CME headed towards us now.
Reposted by David S. F. Portree
The #Geminid meteor shower reaches its peak on the night of December 13–14! Be sure to look up if you have clear skies 💫 #Geminids #astronomy #MeteorShowers #ShootingStars
December 8, 2025 at 1:02 AM
The #Geminid meteor shower reaches its peak on the night of December 13–14! Be sure to look up if you have clear skies 💫 #Geminids #astronomy #MeteorShowers #ShootingStars