In which direction is the sun travelling?
up vote
15
down vote
favorite
Relative to this simple drawing, can someone explain to me,
- in which direction is the sun and its solar system travelling,
- which star (irrespective of distance) is closest to that direction,
- and in which direction the milky way center is.
the-sun
edited Nov 30 at 23:22
RonJohn
1053
asked Nov 30 at 14:35
Alonda
787
migrated from space.stackexchange.com Nov 30 at 15:03
This question came from our site for spacecraft operators, scientists, engineers, and enthusiasts.
add a comment |
up vote
15
down vote
favorite
Relative to this simple drawing, can someone explain to me,
- in which direction is the sun and its solar system travelling,
- which star (irrespective of distance) is closest to that direction,
- and in which direction the milky way center is.
the-sun
edited Nov 30 at 23:22
RonJohn
1053
asked Nov 30 at 14:35
Alonda
787
migrated from space.stackexchange.com Nov 30 at 15:03
This question came from our site for spacecraft operators, scientists, engineers, and enthusiasts.
Closest to that direction is kind of a misnomer here... The sun's closest stellar neighbors are three stars in the Alpha Centauri system, moving at 18.6±1.64 km/s. We're moving at 19.1 km/s. But with expansion and other factors, I don't know, someone smarter can talk about "direction", which I'm assuming you mean "direction relative to the center of our galaxy".
– Magic Octopus Urn
Nov 30 at 15:27
@MagicOctopusUrn Expansion doesn't have any effect at such scales.
– RIanGillis
Dec 3 at 17:12
add a comment |
up vote
15
down vote
favorite
up vote
15
down vote
favorite
Relative to this simple drawing, can someone explain to me,
- in which direction is the sun and its solar system travelling,
- which star (irrespective of distance) is closest to that direction,
- and in which direction the milky way center is.
the-sun
edited Nov 30 at 23:22
RonJohn
1053
asked Nov 30 at 14:35
Alonda
787
Relative to this simple drawing, can someone explain to me,
- in which direction is the sun and its solar system travelling,
- which star (irrespective of distance) is closest to that direction,
- and in which direction the milky way center is.
the-sun
the-sun
edited Nov 30 at 23:22
RonJohn
1053
asked Nov 30 at 14:35
Alonda
787
edited Nov 30 at 23:22
RonJohn
1053
asked Nov 30 at 14:35
Alonda
787
edited Nov 30 at 23:22
RonJohn
1053
edited Nov 30 at 23:22
RonJohn
1053
edited Nov 30 at 23:22
RonJohn
1053
1053
asked Nov 30 at 14:35
Alonda
787
asked Nov 30 at 14:35
Alonda
787
asked Nov 30 at 14:35
Alonda
787
787
migrated from space.stackexchange.com Nov 30 at 15:03
This question came from our site for spacecraft operators, scientists, engineers, and enthusiasts.
migrated from space.stackexchange.com Nov 30 at 15:03
This question came from our site for spacecraft operators, scientists, engineers, and enthusiasts.
Closest to that direction is kind of a misnomer here... The sun's closest stellar neighbors are three stars in the Alpha Centauri system, moving at 18.6±1.64 km/s. We're moving at 19.1 km/s. But with expansion and other factors, I don't know, someone smarter can talk about "direction", which I'm assuming you mean "direction relative to the center of our galaxy".
– Magic Octopus Urn
Nov 30 at 15:27
@MagicOctopusUrn Expansion doesn't have any effect at such scales.
– RIanGillis
Dec 3 at 17:12
add a comment |
Closest to that direction is kind of a misnomer here... The sun's closest stellar neighbors are three stars in the Alpha Centauri system, moving at 18.6±1.64 km/s. We're moving at 19.1 km/s. But with expansion and other factors, I don't know, someone smarter can talk about "direction", which I'm assuming you mean "direction relative to the center of our galaxy".
– Magic Octopus Urn
Nov 30 at 15:27
@MagicOctopusUrn Expansion doesn't have any effect at such scales.
– RIanGillis
Dec 3 at 17:12
Closest to that direction is kind of a misnomer here... The sun's closest stellar neighbors are three stars in the Alpha Centauri system, moving at 18.6±1.64 km/s. We're moving at 19.1 km/s. But with expansion and other factors, I don't know, someone smarter can talk about "direction", which I'm assuming you mean "direction relative to the center of our galaxy".
– Magic Octopus Urn
Nov 30 at 15:27
Closest to that direction is kind of a misnomer here... The sun's closest stellar neighbors are three stars in the Alpha Centauri system, moving at 18.6±1.64 km/s. We're moving at 19.1 km/s. But with expansion and other factors, I don't know, someone smarter can talk about "direction", which I'm assuming you mean "direction relative to the center of our galaxy".
– Magic Octopus Urn
Nov 30 at 15:27
@MagicOctopusUrn Expansion doesn't have any effect at such scales.
– RIanGillis
Dec 3 at 17:12
@MagicOctopusUrn Expansion doesn't have any effect at such scales.
– RIanGillis
Dec 3 at 17:12
add a comment |
3 Answers
3
active
oldest
votes
up vote
9
down vote
accepted
The direction of solar motion is referred to as the solar apex. It is at around RA=18h28m and Dec=+30d in the constellation of Hercules (you can see a map on the page linked to). Note that this is the direction in which you would see the "star wars" effect of onrushing stars diverging from the apex point. i.e. It demonstrates the sun's motion with respect to the local stellar population.
On your 2-dimensional cartoon of the Earth's, the circle is the ecliptic plane and the Earth's northern hemisphere (at winter solstice) is tilted away from the Sun at an angle of 23 degrees. The celestial coordinate system defined above is geocentric and the Sun is at 18h -23d at the winter solstice. The apex point is therefore towards the Sun but 57 degrees above it.
Look at the map below (produced by Christian Ready), you can judge where the solar apex is with respect to the Sun and ecliptic plane (green line), which is roughly the path (drawn in your diagram) that the Earth takes around the Sun.
The very bright star Vega is reasonably close to the solar apex direction.
The Milky way centre is at RA=17h45m, Dec=-29d in the constellation of Sagittarius - i.e. almost where the Sun is in December. In Galactic coordinates (see Best approximation for Sun's trajectory around galactic center? ) the Sun moves at about 10 km/s towards the Galactic centre, about 5 km/s faster than the average circular speed (which is itself about 220 km/s) of local stars in the tangential direction and 7 km/s upwards out of the Galactic plane.
Thus the motion of the Sun with respect to the Galactic centre, as opposed to the local stellar population, is basically at $sim 230$ km/s towards a point that is slightly less than 90 degrees around the Galactic plane and slightly above it. This would be at 9h30m -50d in the constellation of Vela. I think that is into the page and down about 30 degrees in your cartoon.
answered Nov 30 at 16:04
Rob Jeffries
50.9k4101156
so, our direction of travel is "just" 60 degrees off from the center of the milky way? that means we are moving towards it? if our movement was split in two vectors, how fast are we moving towards the center vs perpendicular to it?
– Alonda
Nov 30 at 16:39
@Alonda You have misunderstood what the solar apex is. It shows the velocity relative to local stars. I have added to the answer
– Rob Jeffries
Nov 30 at 18:48
actually I realized that from reading the solar apex page. guess I didnt specify the question well enough. but your addition provided the exact answer I was after. my original question was much about which part of the sky is the "nose" of our solar system "spaceship", where we smash into new galactic debris.
– Alonda
Nov 30 at 18:59
1
@Alonda The orbit is not Keplerian and not elliptical. Roughly, the sun is on a circular orbit with epicycles in and out with a period of 150 Myr and up and down on a period of 70 Myr. Roughly, $sim 10$ km/s inwards for 50 Myr is 500pc. So nowhere near the GC at 8000pc.
– Rob Jeffries
Nov 30 at 20:05
1
"star wars" effect? What you describe sounds more similar to what is shown during warp travel in stark trek than star wars.
– Joshua
Dec 1 at 2:05
|
show 4 more comments
up vote
8
down vote
Relative to your drawing, the sun is moving north-ish:
The solar system is tilted about 60 degrees of the milky way plane, on which it's moving around like everyone else.
To know which star is closest, you'd have to define what "closest" mean. Are we setting a straight line and seeing if it hits any star? If a start is 50 light years away from that straight line and 100 light years away from the sun, is that closer than a start that's 5 light years away from line but 800 light years away from the sun?
The milky way center is to the right of the path the sun is moving on. But I don't know the location when earth is at winter solstice, and you didn't specify northern hemisphere's winter or southern hemisphere's. ;-)
answered Nov 30 at 23:31
msb
1893
1
the animation is a bit confusing. after rob jeffries answer i thought Sol was travelling 60deg off from earths north pole, the animation seems to show the opposite? by closest star I meant, if you had a laser pointer aimed at the direction of travel, which star or stars would be visually closest to the beam. it seems vega is a good answer for me.
– Alonda
Nov 30 at 23:45
My understanding is that the solar system is tilted 60 degrees from the milky way plane. I'm not sure relative to earth's north pole, since earth is also tilted itself relative to the solar system plane. But the animation doesn't show in which way earth is tilted either, so you can't say the animation is following or not the tilt relative to earth's north pole. ;)
– msb
Nov 30 at 23:56
1
I assume the planets orbit the sun counterclockwise... that would make the sun in the animation move in the direction of its south pole. unless my brain malfunctioned.
– Alonda
Dec 1 at 0:44
Oh! That's a good point. Not what I understood from your first comment, but I see what you mean now. Either the sun is travelling south, or the animation is wrong, then either the plane is tilted 60 degrees to the wrong side or the planets are rotating to the wrong side. Good catch! I'm at work now, I'll do a better research later and answer this properly. I'm quite curious about it too. :D Rob Jeffries's answer is very informative, but not straight to the point relative to your questions, hopefully I'll get the straight answers we want. ;)
– msb
Dec 1 at 0:49
add a comment |
up vote
4
down vote
1) and 2) The direction that the Sun is moving is known as the Solar Apex. This Wikipedia article shows a star map, so you can decide which star you want to say is closest. Solar Apex
3) The center of the Milky Way is toward the constellation of Sagittarius.
answered Nov 30 at 15:52
JohnHoltz
2,106138
add a comment |
Your Answer
StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "514"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fastronomy.stackexchange.com%2fquestions%2f28584%2fin-which-direction-is-the-sun-travelling%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
3 Answers
3
active
oldest
votes
3 Answers
3
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
9
down vote
accepted
The direction of solar motion is referred to as the solar apex. It is at around RA=18h28m and Dec=+30d in the constellation of Hercules (you can see a map on the page linked to). Note that this is the direction in which you would see the "star wars" effect of onrushing stars diverging from the apex point. i.e. It demonstrates the sun's motion with respect to the local stellar population.
On your 2-dimensional cartoon of the Earth's, the circle is the ecliptic plane and the Earth's northern hemisphere (at winter solstice) is tilted away from the Sun at an angle of 23 degrees. The celestial coordinate system defined above is geocentric and the Sun is at 18h -23d at the winter solstice. The apex point is therefore towards the Sun but 57 degrees above it.
Look at the map below (produced by Christian Ready), you can judge where the solar apex is with respect to the Sun and ecliptic plane (green line), which is roughly the path (drawn in your diagram) that the Earth takes around the Sun.
The very bright star Vega is reasonably close to the solar apex direction.
The Milky way centre is at RA=17h45m, Dec=-29d in the constellation of Sagittarius - i.e. almost where the Sun is in December. In Galactic coordinates (see Best approximation for Sun's trajectory around galactic center? ) the Sun moves at about 10 km/s towards the Galactic centre, about 5 km/s faster than the average circular speed (which is itself about 220 km/s) of local stars in the tangential direction and 7 km/s upwards out of the Galactic plane.
Thus the motion of the Sun with respect to the Galactic centre, as opposed to the local stellar population, is basically at $sim 230$ km/s towards a point that is slightly less than 90 degrees around the Galactic plane and slightly above it. This would be at 9h30m -50d in the constellation of Vela. I think that is into the page and down about 30 degrees in your cartoon.
answered Nov 30 at 16:04
Rob Jeffries
50.9k4101156
so, our direction of travel is "just" 60 degrees off from the center of the milky way? that means we are moving towards it? if our movement was split in two vectors, how fast are we moving towards the center vs perpendicular to it?
– Alonda
Nov 30 at 16:39
@Alonda You have misunderstood what the solar apex is. It shows the velocity relative to local stars. I have added to the answer
– Rob Jeffries
Nov 30 at 18:48
actually I realized that from reading the solar apex page. guess I didnt specify the question well enough. but your addition provided the exact answer I was after. my original question was much about which part of the sky is the "nose" of our solar system "spaceship", where we smash into new galactic debris.
– Alonda
Nov 30 at 18:59
1
@Alonda The orbit is not Keplerian and not elliptical. Roughly, the sun is on a circular orbit with epicycles in and out with a period of 150 Myr and up and down on a period of 70 Myr. Roughly, $sim 10$ km/s inwards for 50 Myr is 500pc. So nowhere near the GC at 8000pc.
– Rob Jeffries
Nov 30 at 20:05
1
"star wars" effect? What you describe sounds more similar to what is shown during warp travel in stark trek than star wars.
– Joshua
Dec 1 at 2:05
|
show 4 more comments
up vote
9
down vote
accepted
The direction of solar motion is referred to as the solar apex. It is at around RA=18h28m and Dec=+30d in the constellation of Hercules (you can see a map on the page linked to). Note that this is the direction in which you would see the "star wars" effect of onrushing stars diverging from the apex point. i.e. It demonstrates the sun's motion with respect to the local stellar population.
On your 2-dimensional cartoon of the Earth's, the circle is the ecliptic plane and the Earth's northern hemisphere (at winter solstice) is tilted away from the Sun at an angle of 23 degrees. The celestial coordinate system defined above is geocentric and the Sun is at 18h -23d at the winter solstice. The apex point is therefore towards the Sun but 57 degrees above it.
Look at the map below (produced by Christian Ready), you can judge where the solar apex is with respect to the Sun and ecliptic plane (green line), which is roughly the path (drawn in your diagram) that the Earth takes around the Sun.
The very bright star Vega is reasonably close to the solar apex direction.
The Milky way centre is at RA=17h45m, Dec=-29d in the constellation of Sagittarius - i.e. almost where the Sun is in December. In Galactic coordinates (see Best approximation for Sun's trajectory around galactic center? ) the Sun moves at about 10 km/s towards the Galactic centre, about 5 km/s faster than the average circular speed (which is itself about 220 km/s) of local stars in the tangential direction and 7 km/s upwards out of the Galactic plane.
Thus the motion of the Sun with respect to the Galactic centre, as opposed to the local stellar population, is basically at $sim 230$ km/s towards a point that is slightly less than 90 degrees around the Galactic plane and slightly above it. This would be at 9h30m -50d in the constellation of Vela. I think that is into the page and down about 30 degrees in your cartoon.
answered Nov 30 at 16:04
Rob Jeffries
50.9k4101156
so, our direction of travel is "just" 60 degrees off from the center of the milky way? that means we are moving towards it? if our movement was split in two vectors, how fast are we moving towards the center vs perpendicular to it?
– Alonda
Nov 30 at 16:39
@Alonda You have misunderstood what the solar apex is. It shows the velocity relative to local stars. I have added to the answer
– Rob Jeffries
Nov 30 at 18:48
actually I realized that from reading the solar apex page. guess I didnt specify the question well enough. but your addition provided the exact answer I was after. my original question was much about which part of the sky is the "nose" of our solar system "spaceship", where we smash into new galactic debris.
– Alonda
Nov 30 at 18:59
1
@Alonda The orbit is not Keplerian and not elliptical. Roughly, the sun is on a circular orbit with epicycles in and out with a period of 150 Myr and up and down on a period of 70 Myr. Roughly, $sim 10$ km/s inwards for 50 Myr is 500pc. So nowhere near the GC at 8000pc.
– Rob Jeffries
Nov 30 at 20:05
1
"star wars" effect? What you describe sounds more similar to what is shown during warp travel in stark trek than star wars.
– Joshua
Dec 1 at 2:05
|
show 4 more comments
up vote
9
down vote
accepted
up vote
9
down vote
accepted
The direction of solar motion is referred to as the solar apex. It is at around RA=18h28m and Dec=+30d in the constellation of Hercules (you can see a map on the page linked to). Note that this is the direction in which you would see the "star wars" effect of onrushing stars diverging from the apex point. i.e. It demonstrates the sun's motion with respect to the local stellar population.
On your 2-dimensional cartoon of the Earth's, the circle is the ecliptic plane and the Earth's northern hemisphere (at winter solstice) is tilted away from the Sun at an angle of 23 degrees. The celestial coordinate system defined above is geocentric and the Sun is at 18h -23d at the winter solstice. The apex point is therefore towards the Sun but 57 degrees above it.
Look at the map below (produced by Christian Ready), you can judge where the solar apex is with respect to the Sun and ecliptic plane (green line), which is roughly the path (drawn in your diagram) that the Earth takes around the Sun.
The very bright star Vega is reasonably close to the solar apex direction.
The Milky way centre is at RA=17h45m, Dec=-29d in the constellation of Sagittarius - i.e. almost where the Sun is in December. In Galactic coordinates (see Best approximation for Sun's trajectory around galactic center? ) the Sun moves at about 10 km/s towards the Galactic centre, about 5 km/s faster than the average circular speed (which is itself about 220 km/s) of local stars in the tangential direction and 7 km/s upwards out of the Galactic plane.
Thus the motion of the Sun with respect to the Galactic centre, as opposed to the local stellar population, is basically at $sim 230$ km/s towards a point that is slightly less than 90 degrees around the Galactic plane and slightly above it. This would be at 9h30m -50d in the constellation of Vela. I think that is into the page and down about 30 degrees in your cartoon.
answered Nov 30 at 16:04
Rob Jeffries
50.9k4101156
The direction of solar motion is referred to as the solar apex. It is at around RA=18h28m and Dec=+30d in the constellation of Hercules (you can see a map on the page linked to). Note that this is the direction in which you would see the "star wars" effect of onrushing stars diverging from the apex point. i.e. It demonstrates the sun's motion with respect to the local stellar population.
On your 2-dimensional cartoon of the Earth's, the circle is the ecliptic plane and the Earth's northern hemisphere (at winter solstice) is tilted away from the Sun at an angle of 23 degrees. The celestial coordinate system defined above is geocentric and the Sun is at 18h -23d at the winter solstice. The apex point is therefore towards the Sun but 57 degrees above it.
Look at the map below (produced by Christian Ready), you can judge where the solar apex is with respect to the Sun and ecliptic plane (green line), which is roughly the path (drawn in your diagram) that the Earth takes around the Sun.
The very bright star Vega is reasonably close to the solar apex direction.
The Milky way centre is at RA=17h45m, Dec=-29d in the constellation of Sagittarius - i.e. almost where the Sun is in December. In Galactic coordinates (see Best approximation for Sun's trajectory around galactic center? ) the Sun moves at about 10 km/s towards the Galactic centre, about 5 km/s faster than the average circular speed (which is itself about 220 km/s) of local stars in the tangential direction and 7 km/s upwards out of the Galactic plane.
Thus the motion of the Sun with respect to the Galactic centre, as opposed to the local stellar population, is basically at $sim 230$ km/s towards a point that is slightly less than 90 degrees around the Galactic plane and slightly above it. This would be at 9h30m -50d in the constellation of Vela. I think that is into the page and down about 30 degrees in your cartoon.
answered Nov 30 at 16:04
Rob Jeffries
50.9k4101156
edited Dec 1 at 7:43
answered Nov 30 at 16:04
Rob Jeffries
50.9k4101156
answered Nov 30 at 16:04
Rob Jeffries
50.9k4101156
answered Nov 30 at 16:04
Rob Jeffries
50.9k4101156
50.9k4101156
so, our direction of travel is "just" 60 degrees off from the center of the milky way? that means we are moving towards it? if our movement was split in two vectors, how fast are we moving towards the center vs perpendicular to it?
– Alonda
Nov 30 at 16:39
@Alonda You have misunderstood what the solar apex is. It shows the velocity relative to local stars. I have added to the answer
– Rob Jeffries
Nov 30 at 18:48
actually I realized that from reading the solar apex page. guess I didnt specify the question well enough. but your addition provided the exact answer I was after. my original question was much about which part of the sky is the "nose" of our solar system "spaceship", where we smash into new galactic debris.
– Alonda
Nov 30 at 18:59
1
@Alonda The orbit is not Keplerian and not elliptical. Roughly, the sun is on a circular orbit with epicycles in and out with a period of 150 Myr and up and down on a period of 70 Myr. Roughly, $sim 10$ km/s inwards for 50 Myr is 500pc. So nowhere near the GC at 8000pc.
– Rob Jeffries
Nov 30 at 20:05
1
"star wars" effect? What you describe sounds more similar to what is shown during warp travel in stark trek than star wars.
– Joshua
Dec 1 at 2:05
|
show 4 more comments
so, our direction of travel is "just" 60 degrees off from the center of the milky way? that means we are moving towards it? if our movement was split in two vectors, how fast are we moving towards the center vs perpendicular to it?
– Alonda
Nov 30 at 16:39
@Alonda You have misunderstood what the solar apex is. It shows the velocity relative to local stars. I have added to the answer
– Rob Jeffries
Nov 30 at 18:48
actually I realized that from reading the solar apex page. guess I didnt specify the question well enough. but your addition provided the exact answer I was after. my original question was much about which part of the sky is the "nose" of our solar system "spaceship", where we smash into new galactic debris.
– Alonda
Nov 30 at 18:59
1
@Alonda The orbit is not Keplerian and not elliptical. Roughly, the sun is on a circular orbit with epicycles in and out with a period of 150 Myr and up and down on a period of 70 Myr. Roughly, $sim 10$ km/s inwards for 50 Myr is 500pc. So nowhere near the GC at 8000pc.
– Rob Jeffries
Nov 30 at 20:05
1
"star wars" effect? What you describe sounds more similar to what is shown during warp travel in stark trek than star wars.
– Joshua
Dec 1 at 2:05
so, our direction of travel is "just" 60 degrees off from the center of the milky way? that means we are moving towards it? if our movement was split in two vectors, how fast are we moving towards the center vs perpendicular to it?
– Alonda
Nov 30 at 16:39
so, our direction of travel is "just" 60 degrees off from the center of the milky way? that means we are moving towards it? if our movement was split in two vectors, how fast are we moving towards the center vs perpendicular to it?
– Alonda
Nov 30 at 16:39
@Alonda You have misunderstood what the solar apex is. It shows the velocity relative to local stars. I have added to the answer
– Rob Jeffries
Nov 30 at 18:48
@Alonda You have misunderstood what the solar apex is. It shows the velocity relative to local stars. I have added to the answer
– Rob Jeffries
Nov 30 at 18:48
actually I realized that from reading the solar apex page. guess I didnt specify the question well enough. but your addition provided the exact answer I was after. my original question was much about which part of the sky is the "nose" of our solar system "spaceship", where we smash into new galactic debris.
– Alonda
Nov 30 at 18:59
actually I realized that from reading the solar apex page. guess I didnt specify the question well enough. but your addition provided the exact answer I was after. my original question was much about which part of the sky is the "nose" of our solar system "spaceship", where we smash into new galactic debris.
– Alonda
Nov 30 at 18:59
1
1
@Alonda The orbit is not Keplerian and not elliptical. Roughly, the sun is on a circular orbit with epicycles in and out with a period of 150 Myr and up and down on a period of 70 Myr. Roughly, $sim 10$ km/s inwards for 50 Myr is 500pc. So nowhere near the GC at 8000pc.
– Rob Jeffries
Nov 30 at 20:05
@Alonda The orbit is not Keplerian and not elliptical. Roughly, the sun is on a circular orbit with epicycles in and out with a period of 150 Myr and up and down on a period of 70 Myr. Roughly, $sim 10$ km/s inwards for 50 Myr is 500pc. So nowhere near the GC at 8000pc.
– Rob Jeffries
Nov 30 at 20:05
1
1
"star wars" effect? What you describe sounds more similar to what is shown during warp travel in stark trek than star wars.
– Joshua
Dec 1 at 2:05
"star wars" effect? What you describe sounds more similar to what is shown during warp travel in stark trek than star wars.
– Joshua
Dec 1 at 2:05
|
show 4 more comments
up vote
8
down vote
Relative to your drawing, the sun is moving north-ish:
The solar system is tilted about 60 degrees of the milky way plane, on which it's moving around like everyone else.
To know which star is closest, you'd have to define what "closest" mean. Are we setting a straight line and seeing if it hits any star? If a start is 50 light years away from that straight line and 100 light years away from the sun, is that closer than a start that's 5 light years away from line but 800 light years away from the sun?
The milky way center is to the right of the path the sun is moving on. But I don't know the location when earth is at winter solstice, and you didn't specify northern hemisphere's winter or southern hemisphere's. ;-)
answered Nov 30 at 23:31
msb
1893
1
the animation is a bit confusing. after rob jeffries answer i thought Sol was travelling 60deg off from earths north pole, the animation seems to show the opposite? by closest star I meant, if you had a laser pointer aimed at the direction of travel, which star or stars would be visually closest to the beam. it seems vega is a good answer for me.
– Alonda
Nov 30 at 23:45
My understanding is that the solar system is tilted 60 degrees from the milky way plane. I'm not sure relative to earth's north pole, since earth is also tilted itself relative to the solar system plane. But the animation doesn't show in which way earth is tilted either, so you can't say the animation is following or not the tilt relative to earth's north pole. ;)
– msb
Nov 30 at 23:56
1
I assume the planets orbit the sun counterclockwise... that would make the sun in the animation move in the direction of its south pole. unless my brain malfunctioned.
– Alonda
Dec 1 at 0:44
Oh! That's a good point. Not what I understood from your first comment, but I see what you mean now. Either the sun is travelling south, or the animation is wrong, then either the plane is tilted 60 degrees to the wrong side or the planets are rotating to the wrong side. Good catch! I'm at work now, I'll do a better research later and answer this properly. I'm quite curious about it too. :D Rob Jeffries's answer is very informative, but not straight to the point relative to your questions, hopefully I'll get the straight answers we want. ;)
– msb
Dec 1 at 0:49
add a comment |
up vote
8
down vote
Relative to your drawing, the sun is moving north-ish:
The solar system is tilted about 60 degrees of the milky way plane, on which it's moving around like everyone else.
To know which star is closest, you'd have to define what "closest" mean. Are we setting a straight line and seeing if it hits any star? If a start is 50 light years away from that straight line and 100 light years away from the sun, is that closer than a start that's 5 light years away from line but 800 light years away from the sun?
The milky way center is to the right of the path the sun is moving on. But I don't know the location when earth is at winter solstice, and you didn't specify northern hemisphere's winter or southern hemisphere's. ;-)
answered Nov 30 at 23:31
msb
1893
1
the animation is a bit confusing. after rob jeffries answer i thought Sol was travelling 60deg off from earths north pole, the animation seems to show the opposite? by closest star I meant, if you had a laser pointer aimed at the direction of travel, which star or stars would be visually closest to the beam. it seems vega is a good answer for me.
– Alonda
Nov 30 at 23:45
My understanding is that the solar system is tilted 60 degrees from the milky way plane. I'm not sure relative to earth's north pole, since earth is also tilted itself relative to the solar system plane. But the animation doesn't show in which way earth is tilted either, so you can't say the animation is following or not the tilt relative to earth's north pole. ;)
– msb
Nov 30 at 23:56
1
I assume the planets orbit the sun counterclockwise... that would make the sun in the animation move in the direction of its south pole. unless my brain malfunctioned.
– Alonda
Dec 1 at 0:44
Oh! That's a good point. Not what I understood from your first comment, but I see what you mean now. Either the sun is travelling south, or the animation is wrong, then either the plane is tilted 60 degrees to the wrong side or the planets are rotating to the wrong side. Good catch! I'm at work now, I'll do a better research later and answer this properly. I'm quite curious about it too. :D Rob Jeffries's answer is very informative, but not straight to the point relative to your questions, hopefully I'll get the straight answers we want. ;)
– msb
Dec 1 at 0:49
add a comment |
up vote
8
down vote
up vote
8
down vote
Relative to your drawing, the sun is moving north-ish:
The solar system is tilted about 60 degrees of the milky way plane, on which it's moving around like everyone else.
To know which star is closest, you'd have to define what "closest" mean. Are we setting a straight line and seeing if it hits any star? If a start is 50 light years away from that straight line and 100 light years away from the sun, is that closer than a start that's 5 light years away from line but 800 light years away from the sun?
The milky way center is to the right of the path the sun is moving on. But I don't know the location when earth is at winter solstice, and you didn't specify northern hemisphere's winter or southern hemisphere's. ;-)
answered Nov 30 at 23:31
msb
1893
Relative to your drawing, the sun is moving north-ish:
The solar system is tilted about 60 degrees of the milky way plane, on which it's moving around like everyone else.
To know which star is closest, you'd have to define what "closest" mean. Are we setting a straight line and seeing if it hits any star? If a start is 50 light years away from that straight line and 100 light years away from the sun, is that closer than a start that's 5 light years away from line but 800 light years away from the sun?
The milky way center is to the right of the path the sun is moving on. But I don't know the location when earth is at winter solstice, and you didn't specify northern hemisphere's winter or southern hemisphere's. ;-)
answered Nov 30 at 23:31
msb
1893
answered Nov 30 at 23:31
msb
1893
answered Nov 30 at 23:31
msb
1893
answered Nov 30 at 23:31
msb
1893
1893
1
the animation is a bit confusing. after rob jeffries answer i thought Sol was travelling 60deg off from earths north pole, the animation seems to show the opposite? by closest star I meant, if you had a laser pointer aimed at the direction of travel, which star or stars would be visually closest to the beam. it seems vega is a good answer for me.
– Alonda
Nov 30 at 23:45
My understanding is that the solar system is tilted 60 degrees from the milky way plane. I'm not sure relative to earth's north pole, since earth is also tilted itself relative to the solar system plane. But the animation doesn't show in which way earth is tilted either, so you can't say the animation is following or not the tilt relative to earth's north pole. ;)
– msb
Nov 30 at 23:56
1
I assume the planets orbit the sun counterclockwise... that would make the sun in the animation move in the direction of its south pole. unless my brain malfunctioned.
– Alonda
Dec 1 at 0:44
Oh! That's a good point. Not what I understood from your first comment, but I see what you mean now. Either the sun is travelling south, or the animation is wrong, then either the plane is tilted 60 degrees to the wrong side or the planets are rotating to the wrong side. Good catch! I'm at work now, I'll do a better research later and answer this properly. I'm quite curious about it too. :D Rob Jeffries's answer is very informative, but not straight to the point relative to your questions, hopefully I'll get the straight answers we want. ;)
– msb
Dec 1 at 0:49
add a comment |
1
the animation is a bit confusing. after rob jeffries answer i thought Sol was travelling 60deg off from earths north pole, the animation seems to show the opposite? by closest star I meant, if you had a laser pointer aimed at the direction of travel, which star or stars would be visually closest to the beam. it seems vega is a good answer for me.
– Alonda
Nov 30 at 23:45
My understanding is that the solar system is tilted 60 degrees from the milky way plane. I'm not sure relative to earth's north pole, since earth is also tilted itself relative to the solar system plane. But the animation doesn't show in which way earth is tilted either, so you can't say the animation is following or not the tilt relative to earth's north pole. ;)
– msb
Nov 30 at 23:56
1
I assume the planets orbit the sun counterclockwise... that would make the sun in the animation move in the direction of its south pole. unless my brain malfunctioned.
– Alonda
Dec 1 at 0:44
Oh! That's a good point. Not what I understood from your first comment, but I see what you mean now. Either the sun is travelling south, or the animation is wrong, then either the plane is tilted 60 degrees to the wrong side or the planets are rotating to the wrong side. Good catch! I'm at work now, I'll do a better research later and answer this properly. I'm quite curious about it too. :D Rob Jeffries's answer is very informative, but not straight to the point relative to your questions, hopefully I'll get the straight answers we want. ;)
– msb
Dec 1 at 0:49
1
1
the animation is a bit confusing. after rob jeffries answer i thought Sol was travelling 60deg off from earths north pole, the animation seems to show the opposite? by closest star I meant, if you had a laser pointer aimed at the direction of travel, which star or stars would be visually closest to the beam. it seems vega is a good answer for me.
– Alonda
Nov 30 at 23:45
the animation is a bit confusing. after rob jeffries answer i thought Sol was travelling 60deg off from earths north pole, the animation seems to show the opposite? by closest star I meant, if you had a laser pointer aimed at the direction of travel, which star or stars would be visually closest to the beam. it seems vega is a good answer for me.
– Alonda
Nov 30 at 23:45
My understanding is that the solar system is tilted 60 degrees from the milky way plane. I'm not sure relative to earth's north pole, since earth is also tilted itself relative to the solar system plane. But the animation doesn't show in which way earth is tilted either, so you can't say the animation is following or not the tilt relative to earth's north pole. ;)
– msb
Nov 30 at 23:56
My understanding is that the solar system is tilted 60 degrees from the milky way plane. I'm not sure relative to earth's north pole, since earth is also tilted itself relative to the solar system plane. But the animation doesn't show in which way earth is tilted either, so you can't say the animation is following or not the tilt relative to earth's north pole. ;)
– msb
Nov 30 at 23:56
1
1
I assume the planets orbit the sun counterclockwise... that would make the sun in the animation move in the direction of its south pole. unless my brain malfunctioned.
– Alonda
Dec 1 at 0:44
I assume the planets orbit the sun counterclockwise... that would make the sun in the animation move in the direction of its south pole. unless my brain malfunctioned.
– Alonda
Dec 1 at 0:44
Oh! That's a good point. Not what I understood from your first comment, but I see what you mean now. Either the sun is travelling south, or the animation is wrong, then either the plane is tilted 60 degrees to the wrong side or the planets are rotating to the wrong side. Good catch! I'm at work now, I'll do a better research later and answer this properly. I'm quite curious about it too. :D Rob Jeffries's answer is very informative, but not straight to the point relative to your questions, hopefully I'll get the straight answers we want. ;)
– msb
Dec 1 at 0:49
Oh! That's a good point. Not what I understood from your first comment, but I see what you mean now. Either the sun is travelling south, or the animation is wrong, then either the plane is tilted 60 degrees to the wrong side or the planets are rotating to the wrong side. Good catch! I'm at work now, I'll do a better research later and answer this properly. I'm quite curious about it too. :D Rob Jeffries's answer is very informative, but not straight to the point relative to your questions, hopefully I'll get the straight answers we want. ;)
– msb
Dec 1 at 0:49
add a comment |
up vote
4
down vote
1) and 2) The direction that the Sun is moving is known as the Solar Apex. This Wikipedia article shows a star map, so you can decide which star you want to say is closest. Solar Apex
3) The center of the Milky Way is toward the constellation of Sagittarius.
answered Nov 30 at 15:52
JohnHoltz
2,106138
add a comment |
up vote
4
down vote
1) and 2) The direction that the Sun is moving is known as the Solar Apex. This Wikipedia article shows a star map, so you can decide which star you want to say is closest. Solar Apex
3) The center of the Milky Way is toward the constellation of Sagittarius.
answered Nov 30 at 15:52
JohnHoltz
2,106138
add a comment |
up vote
4
down vote
up vote
4
down vote
1) and 2) The direction that the Sun is moving is known as the Solar Apex. This Wikipedia article shows a star map, so you can decide which star you want to say is closest. Solar Apex
3) The center of the Milky Way is toward the constellation of Sagittarius.
answered Nov 30 at 15:52
JohnHoltz
2,106138
1) and 2) The direction that the Sun is moving is known as the Solar Apex. This Wikipedia article shows a star map, so you can decide which star you want to say is closest. Solar Apex
3) The center of the Milky Way is toward the constellation of Sagittarius.
answered Nov 30 at 15:52
JohnHoltz
2,106138
answered Nov 30 at 15:52
JohnHoltz
2,106138
answered Nov 30 at 15:52
JohnHoltz
2,106138
answered Nov 30 at 15:52
JohnHoltz
2,106138
2,106138
add a comment |
add a comment |
Thanks for contributing an answer to Astronomy Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Some of your past answers have not been well-received, and you're in danger of being blocked from answering.
Please pay close attention to the following guidance:
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fastronomy.stackexchange.com%2fquestions%2f28584%2fin-which-direction-is-the-sun-travelling%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Closest to that direction is kind of a misnomer here... The sun's closest stellar neighbors are three stars in the Alpha Centauri system, moving at 18.6±1.64 km/s. We're moving at 19.1 km/s. But with expansion and other factors, I don't know, someone smarter can talk about "direction", which I'm assuming you mean "direction relative to the center of our galaxy".
– Magic Octopus Urn
Nov 30 at 15:27
@MagicOctopusUrn Expansion doesn't have any effect at such scales.
– RIanGillis
Dec 3 at 17:12