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A star/black hole pair near Earth reminds me of the set up if Greg Egan's Diaspora , a delightful far-future transhumanist hard sf novel people here would enjoy.
(Diaspora is a much more appealing story, at least for me, and probably my fave of his novels, but Incandescence does something unique: a discovery fiction of people figuring out elements of general relativity before newtonian mechanics.)
Can anyone elaborate why it is important to put the name of the mission in the designation of the object? There are more important attributes that which could be encoded in the name, are there not?
Earlier quoted context omitted.
But then we wouldn't be seeing it at a distance of 1560 ly right now.
In principle it could be approaching us at near the speed of light (for example, if it was hit by something big going near the speed of light from the other direction a few days after the presently observed light was emitted) and we would never know it until it's just about too late. The same, of course, could be said for any other celestial body, currently observed or otherwise.
But why bother with this black hole? If you want to go that route, why not just imagine that there could be a 100-solar-mass something headed directly at us at 0.9 c, and it will show up tomorrow?
From the press release: > The distance between star and companion is about the same as the average Earth-Sun distance So quite close.
Earlier quoted context omitted.
But then we wouldn't be seeing it at a distance of 1560 ly right now.
In principle it could be approaching us at near the speed of light (for example, if it was hit by something big going near the speed of light from the other direction a few days after the presently observed light was emitted) and we would never know it until it's just about too late. The same, of course, could be said for any other celestial body, currently observed or otherwise.
The reason we wouldn't be able to know until it's too late is due to the nature of light and the speed at which information can travel.
When we observe celestial objects like stars or black holes, we do so by detecting the light they emit or the effects they have on nearby objects. The speed of light is approximately 299,792 kilometers per second (km/s) in a vacuum. This speed is the fastest anything can travel, including information.
In the hypothetical scenario presented in the comments, if a black hole or any celestial body was approaching Earth at near the speed of light, the light (or information) about its approach would be traveling towards us at almost the same speed as the object itself. This means that by the time we receive and process the information about its approach, the object would already be dangerously close to us.
In simpler terms, imagine you and a friend are racing towards a finish line, and your friend is just slightly slower than you. If you start the race at the same time, you'll reach the finish line almost simultaneously. In this analogy, you represent the light (information) and your friend represents the celestial object. Since the information about the approaching object is only slightly ahead of the object itself, we wouldn't have much time to react or prepare once we become aware of the threat.
In the case of the black hole discussed in the comments, if it were moving towards us at near the speed of light, we wouldn't know it until it was almost upon us, making it too late to effectively respond or take any meaningful action to protect ourselves.
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Human comment: Near light speeds are a fascinating topic, that even though I claim basic understanding it always defies intuition.
Can anyone elaborate why it is important to put the name of the mission in the designation of the object? There are more important attributes that which could be encoded in the name, are there not?
Maybe something interesting is in these links:
https://en.wikipedia.org/wiki/Astronomical_naming_convention...
> The black hole is actually quite special. It is different from all other known black holes, and its existence is difficult to explain with standard binary evolution models. Given this and the difficulty in spotting dormant black holes, it will be interesting to see if these black holes are suprisingly common. Similar to the way gravitational microlensing led astronomers to find far more low-mass planets than they e…
If you are looking if something is "surprising" then it is not surprising, by very definition. We know BHs should be pretty common. Earlier generations of stars were composed of larger and more short lived stars (due to their low metallicity) that should mostly end up as black holes. As to detecting gravitational microlensing it is not as easy as it sounds. A black hole remnant of a star will be microlensing the ligh…
Earlier quoted context omitted.
Your reaction should be "astronomy fun fact, that will have no direct effects on anyone's life." This black hole is so dim and distant that it required a super powerful telescope to even notice it exists. It will have no effect on life on earth, except by adding to scientific understanding of the cosmos. Moreover, black holes aren't death machines or anything. This black hole puts out much less light and energy than…
A lot of people seem to have the impression that black holes are like vacuum cleaners, sucking up anything that comes near. If the Sun were replaced with a black hole of equal mass, apart from the heat and light going out, we wouldn't notice anything. All the planets would still orbit more-or-less the same.