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7 votes
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New evidence found for Planet 9
36 votes -
ESA satellites to test razor-sharp formation flying
9 votes -
This super-Earth is the first planet confirmed to have a permanent dark side
29 votes -
Astronomers unveil strong magnetic fields spiraling at the edge of Milky Way’s central black hole
10 votes -
US astronomers fight to save X-ray telescope as NASA dishes out budget cuts
14 votes -
Solar viewer for the upcoming eclipse
21 votes -
NASA’s x-ray telescope faces a long goodbye
12 votes -
Webb & Hubble confirm Universe’s expansion rate
22 votes -
TRAPPIST-1 caught stripping atmosphere of possibly habitable exoplanet
12 votes -
The Greenwich meridian's forgotten rival
4 votes -
How do supermassive black holes get supermassive?
13 votes -
Zoozve
20 votes -
Astronomers accidentally discover dark primordial galaxy without stars
25 votes -
Uncovering the forgotten female astronomers of Yerkes Observatory
15 votes -
Astronomers make rare exoplanet discovery, and a giant leap in detecting Earth-like bodies
15 votes -
Don't look so blue, Neptune: New study (re)reveals Neptune's blue hue to be very pale and similar to Uranus, unlike edited Voyager 2 images
17 votes -
2023's most spectacular photos from the James Webb Telescope
31 votes -
A six-planet system in perfect synchrony has been found in the Milky Way
55 votes -
The strange clouds of alien worlds
6 votes -
The achievement of gender parity in a large astrophysics research centre
7 votes -
The brightest gamma-ray burst ever recorded rattled Earth's atmosphere
18 votes -
First images of ESA-telescope 'Euclid'
22 votes -
What would happen if the Earth had rings?
4 votes -
A giant European telescope rises as US rivals await rescue
8 votes -
NASA's Webb makes first detection of heavy element from star merger
15 votes -
Occultation of the Sun by Lunar Mountains - Oct. 14th, 2023
6 votes -
Any amatuer (or professional) astrophotographers capture the annular solar eclipse today?
I was only able to see ~70% coverage in my area, and was hoping to see some posts here on Tildes about the eclipse. I'd love to see anyone's work they managed to capture today.
20 votes -
Humans have been predicting eclipses for thousands of years, but it’s harder than you might think
11 votes -
James Webb telescope makes 'JuMBO' discovery of planet-like objects in Orion
12 votes -
Search for gravitational waves associated with fast radio bursts detected by CHIME/FRB during the LIGO–Virgo observing run O3a
7 votes -
'Noctalgia' is a feature of the modern age for humans, animals suffer from the loss of dark skies too
16 votes -
NASA’s Webb finds carbon source on surface of Jupiter’s moon Europa
24 votes -
Confirming very bright galaxies in the early universe, while also disproving the identification of what would have been the most distant galaxy ever found
9 votes -
Planet K2-18 b has an ocean and atmosphere that could support life
24 votes -
How to see a newly-discovered green comet this week, before it vanishes for 400 years
11 votes -
Searching for dark matter with the world's most sensitive radio
8 votes -
In photos: The rise of the super blue moon spectacle
15 votes -
XRISM will be launching Sunday, Aug 27 at 8:26pm, EDT (Aug 28, 0:26:22 UTC)
6 votes -
How a Harvard professor became the world’s leading alien hunter
12 votes -
Where did the term blue moon come from, and how rare is the ‘super blue moon’ later this month?
6 votes -
Cyberattack shutters major NSF-funded telescopes for more than two weeks
18 votes -
Clouds on Neptune perform a surprise disappearing act
15 votes -
Closing down an icon: Although Arecibo Observatory is slated to become an education center, astronomers hope research might one day return to the site
13 votes -
Tiny meteorites are everywhere - here's how to find them
7 votes -
The Ring Nebula comes into focus, and it's astounding
33 votes -
Researchers find ancient high-energy impacts could have fueled Venus’s volcanism
12 votes -
Two-faced star seems to have one hydrogen side and one helium side
17 votes -
We could see the glint off giant cities on alien worlds, suggests paper
11 votes -
A new, thin-lensed telescope design could far surpass James Webb – goodbye mirrors, hello diffractive lenses
15 votes -
Turns out, our solar system is the rarest planetary system out there
53 votes -
How I discovered the Hummingbird Nebula
9 votes -
New 3D visualization by NASA highlights 5,000 galaxies revealed by Webb
14 votes -
Harvard professor Avi Loeb has found fragments of a meteoroid that he believes could be from a spacecraft from another civilization or some technological gadget
33 votes -
Dr. Angela Collier, theoretical physicist, discusses aliens, crackpots, and Avi Loeb
18 votes -
Black hole ripples could help pin down expansion of universe
6 votes -
We're back at the Royal Astronomical Society to look at some awesome antique moon globes
9 votes -
Astronomer here! AMA!
I'm here on the invitation of someone else, and not sure what this new website is all about yet/ the space stuff seems pretty scant, so anyone got a question about space they need answering? For...
I'm here on the invitation of someone else, and not sure what this new website is all about yet/ the space stuff seems pretty scant, so anyone got a question about space they need answering?
For those who don't know me from the certain other website, I am a radio astronomer currently at the Center for Astrophysics | Harvard & Smithsonian. Known under this user account on a certain other website for comments that begin with "astronomer here!"
122 votes -
Seven amazing accomplishments the James Webb Telescope achieved in its first year
44 votes -
What is a blue moon and when is the next one?
12 votes -
Can you set a clock using a light sensor to detect sunrise and sunset?
While pondering an off-grid microcontroller project, I got to wondering: A light sensor can obviously detect day vs night. So it could be used as a very cheap way to set a device's clock - but how...
While pondering an off-grid microcontroller project, I got to wondering: A light sensor can obviously detect day vs night. So it could be used as a very cheap way to set a device's clock - but how accurately? To within an hour? A few minutes? How would you do it?
Questions that arose from this include:
- Should it detect dawn/dusk (light <-> dark transition), or noon/midnight (brighest/darkest time) ?
- How do dawn/dusk times relate to clock time? Does it depend on lat/long?
- If using dawn/dusk, what light level threshold to use?
- The same threshold for dawn & dusk, or different ones?
- Better to detect a darker threshold (start of dawn, end of dusk) or a lighter one?
- Some days will be lighter/darker than others, so how to manage averaging of times?
- How accurate could it be made?
My naïve first stab at this would be: Pick a light threshold. Record the dawn/dusk times according to that threshold. Average them, call that "noon", and gradually tweak the clock time over several days to bring it into line with the sensed/calculated "noon" - but a searching for graphs of sunrise/sunset times quickly showed that the midpoint of sunrise & sunset is not noon.
Googling threw up lots of results for sensor lights combining a clock and a photocell, but I couldn't find anything about using the photocell to set the clock. So does anyone know if this has been tried before? Is it a non-starter for some reason?
Edit:
Perhaps it's worth sharing the project I had in mind, which is a rain alarm so I can rush out and get the washing in from the line when it starts to rain. I was thinking how annoying it would be if I left it switched on and it rained in the middle of the night and the alarm woke me up. So I decided should automatically avoid triggering during the sleeping hours of night (say 10pm to 8am). My first thought was a photocell so it wouldn't trigger when it's dark. Then I remembered that it gets light at 3am at the moment, which wouldn't work. So it needs a clock. How to set the clock:
- Manually - Needs a user interface with buttons and a display. Seems overkill just for a clock.
- Serial port - Clunky to plug a laptop in just to set the clock.
- WiFi - Needs a username and password or WPS, and an ESP32 or similar - again seems overkill just to get the time.
- GPS - also overkill and expensive.
19 votes -
Any astrophotographers here? Share some nebula and galaxy shots!
12 votes -
Quasar hunting in amateur astrophotography
I'm not sure how big the astrophotography community, if any, is on ~tildes but I'd figure I'd open a topic up and see! Astrophotography is one of my hobbies, and it was brought to my attention...
I'm not sure how big the astrophotography community, if any, is on ~tildes but I'd figure I'd open a topic up and see! Astrophotography is one of my hobbies, and it was brought to my attention (see link for two quasars near the M3 globular cluster) that it's actually pretty easy to photograph quasars. The same are visible in my attempt at photographing M3. Anyway, my question here is does anybody know of any particular interesting or distant quasars to photograph? I assume most will just be "dots" but it still sounds like fun since they're among the most distant objects you can see. I assume most quasars would be broad spectrum, so no filters are really needed, but I'm also curious if there's any bright yet redshifted objects you'd need infrared to capture.
My setup is an Astro-Tech AT80EDT 80mm Refractor f/6. I just got the f/0.8 reducer which I'm excited to take for a spin. It's a chonky piece of glass. My camera is a ZWO ASI585MC which does decent enough for deep sky.
Edit: To add, using something like http://simbad.u-strasbg.fr/simbad/ is great for finding interesting objects once I've already taken a photo, but it's less helpful to plan my shots.
13 votes -
Planet that shouldn't exist found
13 votes -
Life in the cosmos: JWST hints at lower number of habitable planets
36 votes -
Key building block for life found at Saturn's moon Enceladus
9 votes -
APOD - Astronomy Picture of the Day
20 votes -
NASA’s Webb proves galaxies transformed the early universe
10 votes -
Webb adds another ringed world with new image of Uranus
8 votes -
Black holes are accelerating the expansion of the Universe, say cosmologists
9 votes -
Webb telescope spots super old, massive galaxies that shouldn’t exist
16 votes -
“What If?” Eleven serious answers to slightly crazy science questions
3 votes -
The James Webb space telescope is finding too many early galaxies
14 votes -
A software glitch forced the Webb Space Telescope into safe mode. The $10 billion observatory didn’t collect many images in December, due to a now-resolved software issue.
16 votes -
Construction begins on Australia’s Square Kilometre Array telescope
10 votes -
Astronomer incorrectly suspended from Twitter by automatic moderation
6 votes -
Brightest-ever space explosion reveals possible hints of dark matter
11 votes -
Sofia, the historic airplane-borne telescope, lands for the last time
5 votes -
Finnish radio telescope aims to protect satellites from solar storms – Metsahovi Radio Observatory has been tracking the Sun's solar cycles for decades
3 votes -
Frank Drake, creator of the Drake equation and Project Ozma, dies at 92
9 votes -
One great article about every planet in the solar system
4 votes -
New photos of Jupiter by the JWST
22 votes -
Webb telescope reveals unpredicted bounty of bright galaxies in early universe
10 votes -
Top scientist admits 'space telescope image' was actually a slice of chorizo
23 votes -
Webb: The world is about to be new again
24 votes -
First image from the James Webb Space Telescope
@NASA: It's here-the deepest, sharpest infrared view of the universe to date: Webb's First Deep Field.Previewed by @POTUS on July 11, it shows galaxies once invisible to us. The full set of @NASAWebb's first full-color images & data will be revealed July 12: https://t.co/63zxpNDi4I pic.twitter.com/zAr7YoFZ8C
36 votes -
There are more galaxies in the Universe than even Carl Sagan ever imagined
10 votes -
James Webb Space Telescope - MIRI’s sharper view hints at new possibilities for science
9 votes -
Autopsy of Adam & Eve: Looking at a selection of paper instruments from the 15th-17th century, at the Royal Society
3 votes -
Bygone visions of cosmic neighbors
3 votes -
Depth of field
5 votes -
James Webb: 'Fully focused' telescope beats expectations
13 votes -
International Astronomical Union establishes centre to coordinate response to satellite constellations
5 votes -
What might the new Webb telescope discover?
15 votes -
What picture did Nasa take on my birthday? How to find your Hubble Telescope photo using the APOD calendar.
8 votes -
Where is Webb?
31 votes -
The James Webb Space Telescope has fully opened its mirror and completed its deployment
31 votes -
Webb telescope successfully unfurls its tennis court-size sunshield in space
26 votes -
NASA says Webb’s excess fuel likely to extend its lifetime expectations
19 votes -
Detailed footage finally reveals what triggers lightning
12 votes