Questions tagged [the-sun]

Questions regarding the Sun, or Sol in Latin, the star at the center of the solar system Earth is in.

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2 votes
3 answers
8k views

What is the gravitational acceleration of the Sun?

What is the gravitational acceleration of the Sun? I've seen numbers such as 274 m/s2, but that doesn't make sense to me seeing that relatively weak sources of spacecraft thrust such as Electric ...
2 votes
3 answers
202 views

Disposing of Obsolete Satellites by Propelling to the Sun

I'm not scientifically adept, so bear with me. Would it be feasible to retain enough fuel on new satellites/space stations, etc., that we could dispose of them when obsolete by sending them to the ...
5 votes
3 answers
973 views

Is disabling glare common in space?

I'd like to know if astronauts have been under the effect of Disabling Glare, how easily this could accidentally happen and how long can last if this happen?
0 votes
0 answers
130 views

Why is the Sun influence a mere perturbation to the Moon NRHO (the orbit the Gateway should be put in the context of project Artemis)?

An article of the relevant literature Heliocentric Escape and Lunar Impact from Near Rectilinear Halo Orbits asserts: "As the spacecraft departs the immediate vicinity of the NRHO, the effects of ...
4 votes
1 answer
193 views

Strange swirls on the latest image from SOHO

Earlier today, I was looking at the latest image from SOHO and noticed some odd swirly lines at the bottom left of the image. They no longer appear on the site, but I saved the image before they were ...
13 votes
3 answers
3k views

Does NASA have spacecraft that are specifically made for orbiting around the Sun?

Does NASA have projects with spacecraft which are specifically made for orbiting somewhere around the Sun? If yes, what can they be used for?
7 votes
1 answer
2k views

For an object in a geostationary orbit to have the same apparent diameter as the sun, how big would it have to be?

I know this is just a maths question, but sorry I can't work it out :p Suppose you wanted to make something like Mr Burns' sun blocker: But in orbit, not attached to ...
1 vote
1 answer
145 views

Distance between Sun and Earth using JPL horizons

Using the JPL Horizons app at https://ssd.jpl.nasa.gov/horizons/app.html#/ would someone help to calculate the distance between the Sun and the Earth say 1 May 2023 00:00 UT? I used the following for ...
0 votes
0 answers
143 views

What exactly is PDCSAP flux used in kepler missions?

I am having trouble finding a good explanation for what PDCSAP flux is. One place it's mentioned is here. What exactly is PDCSAP flux is in relation to something like the apparent magnitude of a star?
4 votes
2 answers
440 views

Icy Hot Astronauts [duplicate]

According to the specifications of the Apollo 13 lunar module where the astronauts were during their emergency return to Earth, the walls were about the thickness of a coke can so how were they able ...
1 vote
1 answer
300 views

If JWST can look into 13 billion years past then why it cannot check sun formation which happened only 4.603 billion years ago?

If JWST can look into past then why it cannot find how the sun formed 4.603 billion years back? I heard that JWST will process infrared light waves to make them more clear to the human eye but not it ...
5 votes
1 answer
1k views

How far is the solar system's center of mass from the sun? [duplicate]

We often say that the planets orbit the sun. But, in reality, they orbit the solar system's collective center of mass. How far is that point from the center of the sun?
2 votes
1 answer
186 views

GMAT Sun Ephemeris Output

I need the sun's position vector for an analysis, conducted in Matlab. Thus, I let output the ephemeris files for the spacecrafts and additionally I would like to do the same with the sun. A Report ...
9 votes
3 answers
555 views

What would happen to an astronaut on the surface of Mars if a Carrington-event-like superflare hit the red planet?

If a coronal mass ejection with the intensity of the Carrington event1 or more hit Mars, what would happen to an astronaut on its surface who is too far from their base to return to in time? Assuming ...
12 votes
1 answer
192 views

What are the moving particles that can be seen by the Parker Solar Probe?

There ate two images below from the Parker Probe, one of Venus and the second from the Sun. The second one is a screenshot from a recent video (Youtube of Parker imagery while in solar corona). In ...
0 votes
0 answers
64 views

Since we humans are't able to process any dimensions like 4D and 5D, the distance between stars and galexies appers to be too far away [duplicate]

For exmaple a living oraganism of 2D world is unable to perseive a 3D world. Similary, do humans have such limitations to perseive the further dimensions that 3D, that could results in wrong ...
1 vote
6 answers
8k views

Is it possible to stand still in space?

I am wondering to know if it's possible to stand still (no movement at all with respect to the Sun) in space. Can it be possible? I am thinking that when we move upwards from Earth's surface an ...
2 votes
1 answer
156 views

PIR application as a sun sensor

Is there any history or merit to using a PIR (Pyroelectric ("Passive") InfraRed Sensor) as a sun sensor for determining the attitude or position of a Satellite?
5 votes
2 answers
1k views

Orbital Mechanics and Launching into the Sun

Astronomy.com's Here's why we can't just rocket nuclear waste into the sun is an excellent explanation of the delta-V required to launch from Earth orbit into the Sun (30 km/s) vs. to escape from the ...
6 votes
2 answers
541 views

Which spacecraft will be the first for which the Sun would become the second brightest object in the sky?

Which spacecraft will be the first for which the Sun would become the second brightest object in the sky? When that will happen and how far? What would be the most efficient direction to fly in ...
5 votes
1 answer
492 views

How do solar flares and coronal mass ejections create proton storms?

Wikipedia has this to say about solar particle events: A solar particle event (SPE), or "proton storm," occurs when particles (mostly protons) emitted by the Sun become accelerated to very high ...
6 votes
3 answers
495 views

How can a solar storm be predicted?

Satellites like DSCOVR are used to predict solar storms. How does that work? If the satellite is orbiting L1 and "watches" the sun, how can the signal be back on earth before a storm arrives? How ...
15 votes
3 answers
739 views

Will or could the Parker Solar Probe do science at Venus?

Solar Probe Plus will flyby Venus 7 times(!) during 6 years in order to enter its "low" Solar orbit. Will it carry any instrument useful for studying Venus, for example seasonal changes? Would its ...
2 votes
1 answer
405 views

Does the Moon's orbit intersect the Earth's orbit around the Sun?

I know that the Moon's orbital plane makes an angle of 5 degrees with the Earth's orbital plane or the ecliptic. Also, the Moon's orbit intersects the Earth's orbital plane at two nodes - ascending ...
3 votes
2 answers
530 views

Journey to the center of the Sun (best trajectory)

Let's assume there is unlimitedly rich eccentric person living nowadays, who has been just diagnosed with a kind of terminal cancer (estimates are 3 years left) and their last wish is to jump into a ...
-4 votes
1 answer
552 views

The rotation speed of the sun's equator in degrees per second [closed]

I'm just looking for a °/s speed of the suns equator. I'm coding a sun in unreal engine, so I'm looking for its equator speed. I've seen two incorrect posts using different speeds per day, and I'm too ...
2 votes
0 answers
183 views

Would Mars become habitable to life if the sun starts to expand into a red giant? [closed]

If the sun expands then the distance between the sun and mars would become shorter. Thus more heat would reach Mars and perhaps the polar icecaps would melt. Could this lead to a thicker atmosphere ...
1 vote
2 answers
210 views

Does Perseverance have a gnomon on it?

Though How many sundials, Sun compasses and gnomons are there on solar system bodies? is as yet unanswered, Wikipedia's https://en.wikipedia.org/wiki/MarsDial currently tells us that only the ...
1 vote
0 answers
86 views

Will ESA's Solar Orbiter crash into Venus? If so, why?

The BBC News article European SolO probe ready to take on audacious mission links to the ESA video shown below and contains this 5 minute audio interview with NASA deputy project scientist on the ...
6 votes
2 answers
281 views

How deep into the corona could the Parker Solar Probe go without being damaged?

An answer to the question Has any object launched from Earth gone into the Sun? says The probe will repeatedly touch the outer corona until mission end in 2025, with the closest approach being 3.83 ...
2 votes
0 answers
313 views

How to convert body coordinate from Sun reference frame to Earth reference frame?

I have the coordinates of a celestial body w.r.t. Sun , expressed as (x,y,z), at a given time. I need to move this coordinates into a reference frame centered on Earth center, but after reading dozens ...
4 votes
2 answers
191 views

How much energy from the Sun could we get if we use Jupiter or the Earth as an atmospheric lens?

How much energy (watts) from sunlight could arrive to the focal point if we use Jupiter or the Earth as an atmospheric lens by using refraction? How far the focal point would have to be placed for ...
5 votes
1 answer
635 views

How efficient and fast would seven Caplan thrusters be at pushing the Sun and would it be worth building more than one?

I was thinking about stellar engines. One type of stellar engine is the Caplan thruster, which concentrates the star's light onto the star's surface to create beams of solar wind, which are collected ...
4 votes
1 answer
359 views

When the magnetic poles of the Sun flip (once in 11 years), is the Earth hit by more galactic cosmic rays?

The Sun protects us from cosmic rays from beyond the solar system. Every 11 years, the Sun's poles reverse. Solar cosmic rays are greatest during the reversal. During the reversal, are we hit by more ...
23 votes
7 answers
10k views

Do you need 0 km/s velocity to crash into the sun?

I was reading a popular thread about the delta-v required to escape the solar system compared to the delta-v required to crash into the sun. I get it: the earth itself already has a high speed (29.7km/...
4 votes
1 answer
153 views

Could the magnetosphere of Mercury protect humans?

In theory, we built a space station orbiting Mercury like the ISS on Earth. Will the magnetosphere of Mercury similarly protect humans from this radiation (despite being close to the sun)?
4 votes
3 answers
6k views

What dangers are astronauts exposed to when facing the sun?

In this live stream, we have an astronaut facing the sun (we've seen his hands actually): I thought people doing an EVA should avoid the sun at all cost, but here he's facing it. From what kind of ...
73 votes
5 answers
25k views

Why is it easier to escape the solar system than get to Mercury or the Sun?

It has been mentioned several times on this site that it is "easier" (less delta-v, and hence less fuel) to reach the escape velocity of the solar system, than to reach the planet Mercury or ...
4 votes
2 answers
616 views

Was solar newbie Solar Orbiter able to get "closer" to the Sun than Parker Solar Probe so quickly?

The NASA News headline ESA/NASA's Solar Orbiter Returns First Data, Snaps Closest Pictures of the Sun caught my eye because Solar Orbiter (2020-010A) was launched just five months ago whereas Parker ...
3 votes
0 answers
81 views

How does the Solar Orbiter take images so close to the sun without melting its camera?

The EUI on the NASA/ESA Solar Orbiter recently captured the closest ever images of the sun. How is that made possible without destroying the imager?
12 votes
4 answers
6k views

Did any spacecraft ever use the Sun's gravity for acceleration?

Space probes often use planets to accelerate onto a trajectory towards their goal(s) without having to consume too much fuel. But the fastest acceleration would be made through the Sun's gravity if ...
2 votes
2 answers
485 views

Lighting an area of the Earth Surface from LEO

What does the math look like to calculate the size of an object in LEO that when angled off the sun, would illuminate a given portion of the Earth's surface? For example, if I wanted to "light up" a ...
2 votes
1 answer
730 views

How strong is Sun magnetic field on Moon surface? And on Mars?

I wan to calculate the voltage difference generated by sun EM Field on a wire placed on Moon or Mars surface, but I can't find consistent data about solar EM Field. I found different values: The ...
2 votes
2 answers
147 views

Why did ESA's Solar Orbiter mission's target inclination drop from 34 to 25°?

Wikipedia says that: During the planned 7-year mission the orbital inclination will be raised to about 25° But the information below shows that originally the target final inclination was much ...
2 votes
1 answer
153 views

Space and Newton laws

I've read some articles which explain that we can't totally rely on Newtonian gravity concepts for understanding the motion of objects in space. My question is how the use of relativity helps us to ...
18 votes
6 answers
5k views

Could an Apollo crew have been killed by Solar radiation?

The Sun throws lots of high speed protons around. Especially during its sudden and short intensive "events". Much of that is blocked by Earth's magnetosphere and atmosphere. But astronauts work ...
8 votes
3 answers
1k views

What is the Lux value of the Sun and Earth in Low Earth Orbit (altitude=400 km)?

I'm the Attitude Control System team lead on a cube satellite project, and we're trying to use cheap lux sensors to determine the body sun vector (vector adding the lux from each sensor). I want to ...
6 votes
2 answers
600 views

Is the Heliosphere as elliptical as this graphic suggests?

I noticed the following graphic being used in an article discussing the Voyager probes. It also appears on Wikipedia's Heliosphere page: The same page states that: On a broader scale, the motion ...
1 vote
2 answers
2k views

Nuking the Sun?

We know that according to Wikipedia on Nuclear fusion: The Sun is a main-sequence star, and thus generates its energy by nuclear fusion of hydrogen nuclei into helium. In its core, the Sun fuses ...
2 votes
2 answers
70 views

What is ESA's Solar Orbiter's target inclination?

The BBC News article European SolO probe ready to take on audacious mission links to the ESA video shown below and contains this 5 minute audio interview with NASA deputy project scientist on the ...