All Questions
Tagged with backyard-astronomy or amateur-observing
133 questions
42
votes
2
answers
7k
views
Where can I find the positions of the planets, stars, moons, artificial satellites, etc. and visualize them?
What resources are available to find the positions of planets, stars,
moons, artificial satellites, asteroids, and other heavenly bodies?
user21
28
votes
2
answers
157k
views
How much magnification is needed to see the planets of solar system?
I have a 3inch Newtonian reflector telescope with 300 mm focal length. I can use highest magnification of 75x using a 4mm eyepiece. But in 75x I can't see the details of Jupiter what was expected. ...
- 501
21
votes
2
answers
1k
views
How will Starlink affect observational astronomy?
I have recently found that people around the world have been posting observations of a line of moving objects in the sky which is very likely to be a part of Starlink satellite constellation, such ...
- 381
7
votes
2
answers
728
views
How will planets behave in the night sky as seen by Mars colonists?
Certainly among the first colonists on Mars there will be a few people interested in Astronomy enough to enjoy the night sky.
For them, familliar Mars will be missing and there will be a new, ...
- 30.7k
2
votes
1
answer
637
views
Can an average person see stars from the bottom of a well or through cardboard tubes? Definitive answer required!
A debate about seeing stars or planet during the day below this answer to the Aviation SE question At what altitude might a pilot be able to see at least the brightest stars during the day? seems ...
- 30.7k
25
votes
4
answers
4k
views
Are there any double stars that I can actually see orbit each other?
If I had a nice amateur telescope†, are there any multiple star systems that I could observe over a few years or a few decades and actually see the movement of one or both of them over time?
My short ...
- 30.7k
3
votes
1
answer
1k
views
Automated (and hopefully free) systems I can subscribe to sending email or SMS text message when the T Coronae Borealis Nova becomes visible?
My earlier question about predicted potentially observable events Has a gravitational microlensing event ever been predicted? If so, has it been observed? is limited to microlensing.
Now I have just ...
- 30.7k
3
votes
2
answers
242
views
When would we detect a tiny meter size natural satellite in a geostationary orbits?
A natural, tiny (meters-size, maybe 10.000kg mass) natural satellite could be trapped in a geostationary orbit. I wondered for quite some time:
When and how are we able to detect these satellites?
I ...
- 285
13
votes
2
answers
6k
views
What is that donut-shaped object I see in my telescope? [duplicate]
I was looking through my telescope for the first time and came across this weird star. I think its a celestial donut but im not sure.
- 149
6
votes
1
answer
529
views
Requirements to resolve position of Jovian Whistlers up to magnitude of Red Spot with amateur radio equipment?
Can I sense a bright star pointing an eight foot antenna towards it? is a while ago, but the discussion about this question I found very interesting. Please forgive me that I am not an expert in ...
- 5,657
5
votes
1
answer
596
views
How bright is the Crab Pulsar's 30 Hz modulation in visible light? What color is it?
This answer to Has great eyesight been necessary for astronomers? mentions Astronomer Jocelyn Bell Burnell's recounting of a likely first visual observation of a pulsar. This can be found for example ...
- 30.7k
1
vote
2
answers
99
views
Binocular highlights from Tasmania next few weeks?
My friends are visiting southern Australia and Tasmania for the next few weeks.
I am lobbying them to bring my Nikon 8x42 binoculars so they can appreciate the Milky Way and possibly see a few other ...
- 30.7k
23
votes
4
answers
6k
views
How would the night sky look from inside a globular cluster?
When the weather is clear, we can look at the stars. And we normally would see several thousands of them, they all being more than a $\textrm{pc}$ away from us.
Now, there are globular clusters, ...
- 2,749
14
votes
1
answer
2k
views
Apparent size of M31
I am trying to understand something I read on wikipedia about M31.
Wikipedia says that M31 appears more than six times as wide as the full Moon.
But I remember that when I watched it naked eye it ...
- 617
11
votes
1
answer
3k
views
How big a dish do I need for radio astronomy?
I've recently become interested in the idea of building my own small-scale radio telescope. A quick online search finds a few instructions on how to build this using a satellite dish. These suggest a ...
- 843
9
votes
3
answers
16k
views
Why haven't I seen the Moon?
It has been some time since I've seen the Moon. What are the conditions that might affect whether or not the Moon is visible within a 24-hour period?
Please take into consideration any notable ...
- 101
8
votes
2
answers
671
views
How could I see Andromeda as large as in this picture?
In this question an image is shown (repeated below) which gives an idea of the "true" angular extent of the Andromeda galaxy in our sky.
When I see Andromeda it is usually a bit of a smudge ...
- 163k
8
votes
1
answer
325
views
Does this amateur observation hold a record even including robotic searches for supernovae?
The new paper in Nature A surge of light at the birth of a supernova (doi:10.1038/nature25151) describes the fortuitous capture of a supernova "Shock Breakout" - the earliest rise in brightness of a ...
- 30.7k
7
votes
3
answers
26k
views
Why does Venus flicker?
I was watching Venus with the naked eye yesterday at about 7 pm and I noticed that it was flickering, almost like a star.
I have always learned that planets don't flicker to the naked eye, only stars ...
- 390
5
votes
1
answer
577
views
How big will Apophis appear?
How big will Apophis appear in the sky at its closest point of approach in 2029? Will it compare to the moon? How long will it linger as it passes?
5
votes
4
answers
716
views
How can Mercury's sodium tail be imaged?
I recently learned that Mercury has a sodium tail. Can this sodium tail be imaged with a ground based telescope? Is so, what is the minimum setup required to be able to take a picture of it? Do you ...
- 17.7k
4
votes
2
answers
3k
views
Why does this large Newtonian telescope's front cover have two or three holes in it?
The Michael Bernardo video How to use an Equatorial Mount for Beginners shows a large Newtonian telescope on an equatorial mount.
The cover of the telescope's large aperture shows what looks like ...
- 30.7k
3
votes
1
answer
174
views
Why could I so easily see and photograph such a bright totally eclipsed Moon from a bright city road? (May 26, 2021 total lunar eclipse)
Due to scheduling and geometry I could only snap last night's lunar eclipse with an older model cell phone on a pedestrian overpass of a brightly lit city street, but surprisingly the Moon was quite ...
- 30.7k
3
votes
2
answers
600
views
Astromaster Celestron 130 EQ
I brought a new Astromaster 130 EQ and collimated it using a laser. However, whenever I try to observe moon I get a perfect picture but with other planets I see only a bright glowing ball which ...
- 31
18
votes
4
answers
7k
views
Jupiter FM - What are practical and inexpensive ways for the amateur detection of signals from Jupiter, especially of the transit of her moons?
What modifications to a standard AM/FM or shortwave radio are needed in order to be able to detect radio-wave signals emitted from Jupiter?
Would it be possible to detect the transit of the major ...
user8
16
votes
3
answers
2k
views
Was lunar libration first observed or first predicted? In either case, who was the responsible party?
How old is the idea of the far side of the Moon? got me thinking that as soon as we see the moon librate we have to come to terms with there being even more of it we can't see.
The Moon's libration is ...
- 30.7k
10
votes
1
answer
402
views
Can one build a distributed radio telescope?
I understand some radio telescopes are built as arrays of receivers. Could one build an array from a heterogeneous set of receivers in scattered locations? Suppose a large number of persons each ...
- 203
9
votes
2
answers
3k
views
What kind of things I could "see" with an amateur radio telescope?
There are apparently not many reasonably priced radio telescopes available for the amateur users. I only could find a SPIDER 230C 2.3 meter diameter compact radio telescope, which costs ~10 k€. ...
- 394
7
votes
1
answer
1k
views
What radio frequency ranges are most beneficial for astronomy?
I cannot get the idea of citizen radio astronomy out of my head, and choosing an antenna (design) heavily depends on the desired frequency range.
The Arecibo telescope as my gold standard operated 300 ...
- 5,657
7
votes
1
answer
1k
views
Why don't we use amateur astronomers' telescopes to create a huge interferometer?
Some telescopes in space have been proposed to function as an interferometer.
Being placed several hundreds or thousands of kilometers apart they could actual image exoplanets directly. To my ...
- 173
7
votes
2
answers
37k
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What are the advantages and disadvantages of a 2-inch eyepiece versus a 1.25-inch eyepiece?
I'm considering picking up some new eyepieces for my telescope and am interested in comparing 2-inch and 1.25-inch eyepieces. Are there any disadvantages to 2-inch eyepieces? Are 2-inch eyepieces only ...
- 261
6
votes
0
answers
382
views
What would go into the design of a simple sky quality meter, used to measure night sky brightness?
@MCG's answer mentions several methods to classify night sky quality or brightness, and goes on to say:
Additionally, you could always purchase a SQM (Sky quality meter) which is a small, portable ...
- 30.7k
6
votes
0
answers
260
views
Viewing "Diamond Fuji"
Diamond Fuji is a phenomenon in which the (typically) setting sun is positioned directly atop Mt Fuji. Some relatively detailed predictions for viewing times at a nearby park are available here.
I ...
- 161
6
votes
1
answer
383
views
Watching the Mercury transit with improvised devices
I have learned that it is not possible to watch the upcoming Mercury transit with the plain eye (using special filter glasses).
Is it possible to watch the transit with improvised devices (like a ...
- 666
5
votes
3
answers
666
views
What is it about the layout of the three gratings in a Bahtinov mask that makes its indicate focus in this way?
The question Lucky imaging with Celestron 14 - is this result reasonable? includes a beautiful example of a focus test using a Bahtinov mask and the image below from Deep Sky Watch's Home Made ...
- 30.7k
4
votes
0
answers
67
views
Is it possible to use something besides emulsion to directly record the image of a nighttime object using a telescope?
The following questions have got me thinking.
Is it possible to use Photolithography for telescope image sensor?
Fresnel lenses for a makeshift Galilei telescope?
Has anyone ever tried to make a ...
- 30.7k
4
votes
1
answer
2k
views
What have I encountered here?
Consider:
I tried Google Lens to tell the answer, but it is not giving a true answer.
I am using the Android app Stellarium.
- 51
4
votes
1
answer
425
views
How to make a 65 cm lens with a 20 cm hole in it for a Hamiltonian telescope?
This answer to What (the heck) is a Hamiltonian telescope? Is this one? confirms that the telescope in the question linked there is indeed as described and that the first lens is a full 65 cm aperture ...
- 30.7k
4
votes
1
answer
890
views
Under what situations can an aperture mask improve the resolution of a small/medium amateur telescope? Is this demonstrable mathematically?
@antlersoft's answer describes some of the challenges to seeing any details in the small disk of Mars in small amateur telescopes. In the case of reflecting telescopes, it mentions the use of either ...
- 30.7k
3
votes
1
answer
479
views
Why is this telescope so short? How hard is it to make such a fast primary?
The recently discovered object C/2019 Q4 (Borisov) is in the news because it might have an eccentricity greater than one, which means it might be from outside the solar system, though not necessarily.
...
- 30.7k
3
votes
0
answers
105
views
Unknown moving light in sky [duplicate]
On July 13, 2018, while camping in Southwest Oregon, a bright light appeared in the sky at sunset. It was much brighter than Jupiter, also visible. It was moving slowly, west to east. I estimate it ...
- 41
3
votes
1
answer
424
views
Not getting quality images in telescope
I have a Newtonian telescope (Celestron 130 eq) with 5.2 inch (~132 mm) aperture with 650 mm focal length, Spherical mirror. And having 4mm, 10mm, 12.5mm, 20mm,20mm (erecting eyepiece), a 3x and 1.5x ...
- 2,646
2
votes
1
answer
2k
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How to calculate B-V colour index value percentage difference
I need to calculate a percentage difference of a B-V colour index between its estimated and actual value. So I tried doing this by difference between values/actual value x 100. However as B-V values ...
- 123
2
votes
1
answer
489
views
What exactly is a Hamiltonian telescope? Is this one?
This comment on the current answer to Why is this telescope so short? How hard is it to make such a fast primary? says
In this forum topic Borisov appears to call it an f/1.5 Hamiltonian.
Wikipedia'...
- 30.7k
2
votes
1
answer
101
views
Why are Delta Aquariids "for the southern hemisphere" while the Perseids are "for the north"?
In the video How to spot Comet NEOWISE, plus the largest 3D map of the Universe | Night Sky News July 20 after 05:28 Dr. Becky (Smethurst, Oxford astrophysicist) ...
- 30.7k
2
votes
1
answer
158
views
Are there home-brew photometers for amateur observing of variable stars and are they widely used?
Comments on Why do these photometric observations of Betelgeuse look “quantized” in 0.1 magnitude steps? suggest that these are visual estimates, mostly (but not all) to 0.1 magnitude resolution.
Are ...
- 30.7k
1
vote
1
answer
2k
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Choosing an eyepiece for planet viewing
I have a Celestron Astromaster 130EQ which came with a 10mm and 20mm lens. I can not see mars, Jupiter, or Saturn as expected, I only see white dots. What lens should I buy to view these planets.
- 11
48
votes
3
answers
16k
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If Earth is tilted, why is Polaris always above the same spot?
Why is Polaris, the North Star, always above (or near) the North Pole? If Earth is tilted, Polaris' path should be in winter 23 degrees away from its path in summer, or not?
- 379
42
votes
2
answers
1k
views
How do I calculate the inclination of an object with an amateur telescope?
Suppose I would like to calculate the inclination of a satellite from the ecliptic. Would it be possible to do this with an amateur telescope? How would I go about doing so?
Note: A good answer ...
- 6,360
26
votes
4
answers
9k
views
What would happen if someone had a telescope and watched Betelgeuse when it goes supernova?
Would that person go blind?
Neutrino detectors and the abundance of Neutrinos would detect the upcoming visible show about 3 hours before any visible signs, so there would be time to point certain ...
- 24.2k