Cees Bassa
@cbassa.bsky.social
Astronomer at ASTRON in the Netherlands, working with the LOFAR low frequency radio telescope.
Reposted by Cees Bassa
It's cleared up in Sydney and I can see the shadow creeping across the Moon! 🥳🌚🔭
Lunar eclipse fans, there's a total lunar eclipse this weekend! All of Australia (and a bunch of other countries) will be able to see all the best bits. The eclipse will be in the evening of Sunday the 7th or the morning of Monday the 8th of September 🧪🔭🌝
www.abc.net.au/news/science...
www.abc.net.au/news/science...
When and where can I see Monday's total lunar eclipse from Australia?
A total lunar eclipse, also known as a "blood moon", will be visible across all of Australia next week. Here's what you need to know to get the best view and snap the best photo.
www.abc.net.au
September 7, 2025 at 4:38 PM
It's cleared up in Sydney and I can see the shadow creeping across the Moon! 🥳🌚🔭
Reposted by Cees Bassa
💥Greater (partial) success for #amateurradio and #amsat satellite operators in dispute with AST Spacemobile over commercial use of the 430-440 MHz amateur radio band for TT&C! 💥 In its reference Attachment to the recent grant, dated August 29, 2025, the FCC imposes clear limits ⬇️
September 6, 2025 at 12:41 PM
💥Greater (partial) success for #amateurradio and #amsat satellite operators in dispute with AST Spacemobile over commercial use of the 430-440 MHz amateur radio band for TT&C! 💥 In its reference Attachment to the recent grant, dated August 29, 2025, the FCC imposes clear limits ⬇️
Reposted by Cees Bassa
NOAA-15 was decommissioned today at 15:26 UTC, with its AVHRR/3 Instrument still in better state than the last 2 remaining on MetOp-B & C.
It wouldn't be so disappointing if this wasn't done for the wrong reasons... Makes you wonder what happened to NOAA.
It wouldn't be so disappointing if this wasn't done for the wrong reasons... Makes you wonder what happened to NOAA.
August 19, 2025 at 4:39 PM
NOAA-15 was decommissioned today at 15:26 UTC, with its AVHRR/3 Instrument still in better state than the last 2 remaining on MetOp-B & C.
It wouldn't be so disappointing if this wasn't done for the wrong reasons... Makes you wonder what happened to NOAA.
It wouldn't be so disappointing if this wasn't done for the wrong reasons... Makes you wonder what happened to NOAA.
Reposted by Cees Bassa
#skao2025 Federico Di Vruno on impact of satellites on #RadioAstronomy from intended emissions (strong enough to saturate receivers) & unintended electromagnetic radiation (originating from on satellite electronics). In future 🛰️ constellations could impact 25% of our observing time! 🔭📡🧪
June 16, 2025 at 9:53 AM
#skao2025 Federico Di Vruno on impact of satellites on #RadioAstronomy from intended emissions (strong enough to saturate receivers) & unintended electromagnetic radiation (originating from on satellite electronics). In future 🛰️ constellations could impact 25% of our observing time! 🔭📡🧪
Reposted by Cees Bassa
New paper day! In 'Near-future rocket launches could slow ozone recovery', we show that scaling up use of launch vehicles 🚀 has a point where the healing of the ozone layer is affected 🧪🛰️
Open access, free to read & share
Open access, free to read & share
Near-future rocket launches could slow ozone recovery
npj Climate and Atmospheric Science - Near-future rocket launches could slow ozone recovery
rdcu.be
June 10, 2025 at 1:31 AM
New paper day! In 'Near-future rocket launches could slow ozone recovery', we show that scaling up use of launch vehicles 🚀 has a point where the healing of the ozone layer is affected 🧪🛰️
Open access, free to read & share
Open access, free to read & share
Reposted by Cees Bassa
Here, strf was used by the UVSQSat-NG team :
- at the beginning of the mission to optimize the preliminary TLEs so that the university could establish the most reliable communication possible,
- for monitoring purposes since refined TLEs have become available...
Thank you for the great work!
- at the beginning of the mission to optimize the preliminary TLEs so that the university could establish the most reliable communication possible,
- for monitoring purposes since refined TLEs have become available...
Thank you for the great work!
June 7, 2025 at 5:01 PM
Here, strf was used by the UVSQSat-NG team :
- at the beginning of the mission to optimize the preliminary TLEs so that the university could establish the most reliable communication possible,
- for monitoring purposes since refined TLEs have become available...
Thank you for the great work!
- at the beginning of the mission to optimize the preliminary TLEs so that the university could establish the most reliable communication possible,
- for monitoring purposes since refined TLEs have become available...
Thank you for the great work!
Reposted by Cees Bassa
Unfortunately the surface of the Moon is also quite hard.
June 5, 2025 at 7:35 PM
Unfortunately the surface of the Moon is also quite hard.
Reposted by Cees Bassa
We lost HAKUTO-R M2 signal suddenly
June 5, 2025 at 7:18 PM
We lost HAKUTO-R M2 signal suddenly
Reposted by Cees Bassa
We have lost signal of Hakuto-R M2 Resilience! We saw the signal and its Lunar reflection close to each other before LOS, indicating that it was very close to the surface when the signal disappeared. Space is hard!
June 5, 2025 at 7:19 PM
We have lost signal of Hakuto-R M2 Resilience! We saw the signal and its Lunar reflection close to each other before LOS, indicating that it was very close to the surface when the signal disappeared. Space is hard!
Reposted by Cees Bassa
We are now tracking the landing attempt of #Hakuto-R Mission 2 #Resilience. Check our livestream at www.youtube.com/live/C7-MQ2U...
Livestream CAMRAS Radiotelescoop
YouTube video by CAMRAS Radiotelescoop
www.youtube.com
June 5, 2025 at 6:36 PM
We are now tracking the landing attempt of #Hakuto-R Mission 2 #Resilience. Check our livestream at www.youtube.com/live/C7-MQ2U...
Reposted by Cees Bassa
On the occasion of the @unesco.org International Day of Light, we created a 'light painting' using the Dwingeloo Telescope by mounting a light bulb at the focus for half an hour. #lightday2025 @idlofficial.bsky.social
May 16, 2025 at 6:55 AM
On the occasion of the @unesco.org International Day of Light, we created a 'light painting' using the Dwingeloo Telescope by mounting a light bulb at the focus for half an hour. #lightday2025 @idlofficial.bsky.social
Reposted by Cees Bassa
And Magritte fans 😀
May 9, 2025 at 7:29 PM
And Magritte fans 😀
Two days too late and perhaps only funny for those speaking Dutch. (H/T Gemma Janssen.)
May 9, 2025 at 7:14 PM
Two days too late and perhaps only funny for those speaking Dutch. (H/T Gemma Janssen.)
Reposted by Cees Bassa
Maybe the upper stage failure ended up tumbling the spacecraft fast enough to break it up?
April 30, 2025 at 9:35 PM
Maybe the upper stage failure ended up tumbling the spacecraft fast enough to break it up?
Reposted by Cees Bassa
Following up on @marcolangbroek.bsky.social 's post on the upcoming Venera capsule reentry, I've done a writeup describing my own analysis of this object, which I first got interested in a quarter century ago!
planet4589.org/space/debris...
planet4589.org/space/debris...
Probe No. 670 was boosted to solar orbit and named Venera-8 ("Venus-8"). It was launched on 1972 Mar 27 and successfully landed on Venus on 1972 Jul 22, surviving for 50 minutes on the surface.
planet4589.org
April 30, 2025 at 7:30 PM
Following up on @marcolangbroek.bsky.social 's post on the upcoming Venera capsule reentry, I've done a writeup describing my own analysis of this object, which I first got interested in a quarter century ago!
planet4589.org/space/debris...
planet4589.org/space/debris...
Reposted by Cees Bassa
Time for some science again... We are finding new pulsars with CHIME by stacking data over multiple days to boost sensitivity. As always, a huge effort by multiple postdocs, students and programmers.
arxiv.org/abs/2504.16293
arxiv.org/abs/2504.16293
CHIME All-sky Multiday Pulsar Stacking Search (CHAMPSS): System Overview and First Discoveries
We describe the CHIME All-sky Multiday Pulsar Stacking Search (CHAMPSS) project. This novel radio pulsar survey revisits the full Northern Sky daily, offering unprecedented opportunity to detect highl...
arxiv.org
April 29, 2025 at 6:18 PM
Time for some science again... We are finding new pulsars with CHIME by stacking data over multiple days to boost sensitivity. As always, a huge effort by multiple postdocs, students and programmers.
arxiv.org/abs/2504.16293
arxiv.org/abs/2504.16293
Reposted by Cees Bassa
After fixing this mistake, the frequency difference is on the order of 1 Hz. This is about 0.7 ppb, so it is within the accuracy that we could expect for the GPSDO at Bochum. So mystery solved!
April 25, 2025 at 7:40 AM
After fixing this mistake, the frequency difference is on the order of 1 Hz. This is about 0.7 ppb, so it is within the accuracy that we could expect for the GPSDO at Bochum. So mystery solved!
Reposted by Cees Bassa
Great work! This is why we put our IQ on the web :)
One remark on why Dwingeloo is less sensitive: we have a relay in front of the first LNA, because Dwingeloo also transmits in experiments like this one. Apart from that, we may also need a better LNA.
One remark on why Dwingeloo is less sensitive: we have a relay in front of the first LNA, because Dwingeloo also transmits in experiments like this one. Apart from that, we may also need a better LNA.
April 20, 2025 at 8:21 PM
Great work! This is why we put our IQ on the web :)
One remark on why Dwingeloo is less sensitive: we have a relay in front of the first LNA, because Dwingeloo also transmits in experiments like this one. Apart from that, we may also need a better LNA.
One remark on why Dwingeloo is less sensitive: we have a relay in front of the first LNA, because Dwingeloo also transmits in experiments like this one. Apart from that, we may also need a better LNA.
Reposted by Cees Bassa
The signal can be detected both in the Dwingeloo and Stockert 25 m radio telescopes, but the performance of Dwingeloo is poorer. The observed Doppler spread is on the order of ±0.75 Hz, which is a bit less than the spread model I made.
Read more: destevez.net/2025/04/anal...
Read more: destevez.net/2025/04/anal...
April 20, 2025 at 9:04 AM
The signal can be detected both in the Dwingeloo and Stockert 25 m radio telescopes, but the performance of Dwingeloo is poorer. The observed Doppler spread is on the order of ±0.75 Hz, which is a bit less than the spread model I made.
Read more: destevez.net/2025/04/anal...
Read more: destevez.net/2025/04/anal...
Reposted by Cees Bassa
New blog post: Analysis of the CAMRAS Venus radar experiment. A deep dive into the Earth-Venus-Earth L-band radar experiment done in March by @radiotelescoop.bsky.social, Astropeiler Stockert, the Deep Space Exploration Society, and Open Research Institute. 🧵
April 20, 2025 at 9:04 AM
New blog post: Analysis of the CAMRAS Venus radar experiment. A deep dive into the Earth-Venus-Earth L-band radar experiment done in March by @radiotelescoop.bsky.social, Astropeiler Stockert, the Deep Space Exploration Society, and Open Research Institute. 🧵
Reposted by Cees Bassa
Oh dear ... "Mr Eclipse" Fred Espenak just wrote this on a mailing list and on facebook.com/fred.espenak.... The eclipse scene has lost so many of its greatest in the last three years, Jay Pasachof, Serge Kouchmy, Glenn Schneider, and now its towering figure will leave us. :-(
April 16, 2025 at 12:43 AM
Oh dear ... "Mr Eclipse" Fred Espenak just wrote this on a mailing list and on facebook.com/fred.espenak.... The eclipse scene has lost so many of its greatest in the last three years, Jay Pasachof, Serge Kouchmy, Glenn Schneider, and now its towering figure will leave us. :-(
A bit late, but here is some additional analysis of the Earth-Venus-Earth radar experiments with @radiotelescoop.bsky.social from March 22nd, 2025. It takes the 4 recordings at the Dwingeloo and Stockert telescopes and searches in Doppler frequency and Doppler rates for the radar reflections.
April 10, 2025 at 7:26 PM
A bit late, but here is some additional analysis of the Earth-Venus-Earth radar experiments with @radiotelescoop.bsky.social from March 22nd, 2025. It takes the 4 recordings at the Dwingeloo and Stockert telescopes and searches in Doppler frequency and Doppler rates for the radar reflections.
Reposted by Cees Bassa
Just catching up on this excellent #RadioAstronomy work by ProAm group using the Dwingeloo Telescope. 🔭📡
They managed to fire a signal at Venus, and catch the reflection back on two antennas here on Earth!
There is *lots* of nice working coming from this group! 👏👏👏
Blog + link to script below
They managed to fire a signal at Venus, and catch the reflection back on two antennas here on Earth!
There is *lots* of nice working coming from this group! 👏👏👏
Blog + link to script below
We used the historic Dwingeloo telescope to bounce a signal off the surface of Venus, and receive its echo! This marks only the second time that amateurs have achieved an 'EVE' (Earth-Venus-Earth) bounce. Venus was about 40 million kilometers from Earth.
www.camras.nl/en/blog/2025...
www.camras.nl/en/blog/2025...
April 2, 2025 at 3:28 AM
Just catching up on this excellent #RadioAstronomy work by ProAm group using the Dwingeloo Telescope. 🔭📡
They managed to fire a signal at Venus, and catch the reflection back on two antennas here on Earth!
There is *lots* of nice working coming from this group! 👏👏👏
Blog + link to script below
They managed to fire a signal at Venus, and catch the reflection back on two antennas here on Earth!
There is *lots* of nice working coming from this group! 👏👏👏
Blog + link to script below