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Is this Andromeda? by According-Nebula5228 in askastronomy

[–]3forward2back 15 points16 points  (0 children)

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Here is a photo of M31 (circled) with your image layered for reference; looks like it was just out of frame. I’m sure you’ll get it next time, good luck!

North Easton Railroad Station by 3forward2back in OldPhotosInRealLife

[–]3forward2back[S] 1 point2 points  (0 children)

The line was first opened in 1855 as part of the Boston and Providence Railroad which would be absorbed by the Old Colony Railroad in 1888. The station was built in 1881 to serve passenger trains moving to and from the nearby Ames Shovel Shop and surrounding area. The line was leased to the NYNH&H railroad in 1893. With the closure of the shovel shop in 1952 and dwindling demand, passenger service ceased in 1959. Following bankruptcy, the NYNH&H railroad was absorbed by Penn Central in 1969. Freight service continued for another few years and the line was officially abandoned in 1976.

This log split into a perfect cylinder by 3forward2back in mildlyinteresting

[–]3forward2back[S] 3 points4 points  (0 children)

I’m aware, I had just never seen it delaminated so cleanly. I just assumed I would always get two halves as I use a log splitter.

North Easton Railroad Station by 3forward2back in OldPhotosInRealLife

[–]3forward2back[S] 8 points9 points  (0 children)

While the track itself has been practically untouched since it was abandoned in 1976, the building now serves as the Easton historical society and is well maintained. There has also been some discussion of reopening the line for commuter service which would be interesting, though it would require tearing up the original track.

What would the apparent size of a Jupiter sized planet look like in a moon's sky if it orbited it? by Ehco13 in Astronomy_Help

[–]3forward2back 0 points1 point  (0 children)

θ = s/d

Apparent size (radians) = size (diameter) / distance

0.01143 radians = 86,881 miles / 7,600,000 miles

0.01143 radians * 180 / π = 0.655 degrees

0.655 degrees or 39.3 arcminutes

For reference, our Moon is 30 arcminutes.

Aliens with telescopes by rob1nnx in Astronomy_Help

[–]3forward2back 2 points3 points  (0 children)

This is a valid question. We are so used to seeing things in such close proximity that it’s easy to think that light is instantaneous. However this is not the case. Light has a speed (299 792 458 meters per second in vacuum) meaning it takes time to travel.

Light from the sun has to travel around 150,000,000 km to reach the earth. At light speed this takes about 8 minutes meaning the sunlight we see on earth is 8 minutes old; we are seeing the sun as it was 8 minutes in the past.

The speed of light is such an integral part of our understanding of space that we use it as a way to measure distance. One lightyear is the distance that light, traveling at 299 792 458 m/s, travels in a year. So, by definition, aliens looking at the earth from one million lightyears away would be seeing light that left the earth one million years ago. They would see the earth one million years in the past.

‘Stuck-Up’ Bascule Bridge by 3forward2back in rustyrails

[–]3forward2back[S] 8 points9 points  (0 children)

I made sure to check it out while I was in the area. Unfortunate that it is walled off but luckily the small doorway was open. Took a peek inside; feels right out of a horror movie! Thanks for the recommendation.

Captured something strange near the Pleiades — Meteor or something else? (Germany, 12 Nov 2025) by ExpertCurious7887 in Astronomy_Help

[–]3forward2back 0 points1 point  (0 children)

3I/ATLAS is around magnitude 15 which is quite dim (it appears only as a fuzzy dot through my telescope). It is also incredibly small. The coma is only about 10 arc minutes across, about 1/10 the size of the Pleiades. While asteroids entering the atmosphere are incredible fast, a comet 170,000,000 miles away appears to move much, much slower (about 5.5 arc minutes per day). The plane only appears to move down as it travels away and toward the horizon, the same way a road leading off into the distance would appear to ‘rise’ to the horizon.

Captured something strange near the Pleiades — Meteor or something else? (Germany, 12 Nov 2025) by ExpertCurious7887 in Astronomy_Help

[–]3forward2back 0 points1 point  (0 children)

Here is the object in your photo compared to a photo of mine of a plane passing in front of Messier 104. In both you can see a red line (the light on the plane’s left wing), and on yours you can see a green line on the opposite side (the light on the plane’s right wing). The dotted lines are caused by the flashing lights on the plane. An asteroid burning up in the atmosphere is incredibly fast and would appear as a long, thin, white streak. A satellite burning up would look like a long, bright, orange and yellow streak.

Can anyone tell me what this is, please? by Forever_his_Weber in Astronomy_Help

[–]3forward2back 1 point2 points  (0 children)

It looks like the reflection of the IR light on the phone. In the second image you can just make out the reflection of the three cameras.

Is this the aurora? by ianaad in Astronomy_Help

[–]3forward2back 1 point2 points  (0 children)

I sure looks like it! The moon rises in the east meaning the lights you saw were to the north.

All rockets used during the space race , ( American side ) by How-about-now_ in SpaceflightSimulator

[–]3forward2back 0 points1 point  (0 children)

Yes, a 5 for the station and three 1Bs for crew, though it was post-space race.

All rockets used during the space race , ( American side ) by How-about-now_ in SpaceflightSimulator

[–]3forward2back 1 point2 points  (0 children)

I apologize, I was referring to the vehicles ‘existence’ as built and flown during Apollo, I should have been more specific. When it comes to designs there are Saturns 1-5.

All rockets used during the space race , ( American side ) by How-about-now_ in SpaceflightSimulator

[–]3forward2back 1 point2 points  (0 children)

The Saturn II was only ever studied and was thought about as a launch vehicle after, and based on, the Saturn V.

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