# Tag Info

18

NEOs are mostly found as dots in images taken by various telescopes, often those of amateurs (as in not paid, nothing about skill or equipment). By taken repeated images days apart moving dots can be picked out against the static background stars and an orbit plotted. Then that orbit is matched against known objects, and used to either add a new object to ...

13

Definitely - it could be ejected. But Earth would only play a minor role. Starman now counts as a Near Earth Object, being any object crossing Earth's orbit. Any such object is occasionally in Earth's vicinity, when they cross our orbit while we are nearby. The orbits of such objects have now been modeled over time periods of millions of years. From ...

11

It would take vastly more $\Delta V$ to get it to a low-Earth orbit. The targets selected are close enough to Earth's orbit about the Sun that it only takes around $200\,\mathrm{m/s}$ to get it into a distant retrograde orbit about the Moon. To get the thing to a low Earth orbit would be around $3\,\mathrm{km/s}$. The tyranny of the rocket equation makes ...

6

Asteroid 2010 TK7 is called an Earth Trojan. But it's orbit isn't as long lived as the Jupiter Trojans. According to Wikipedia: 2010 TK7's orbit has a chaotic character, making long-range predictions difficult. Prior to A.D. 500, it may have been oscillating about the L5 Lagrangian point (60 degrees behind Earth), before jumping to L4 via L3. Short-term ...

6

OSIRIS-REx is packed all full of good stuff. I'll throw together a quick list of the scanning ones you're interested in. Also of note is that the entire spacecraft will be making that scanning motion shown in the gif, so as the asteroid rotates, all of these instruments will be able to have full coverage of it. OSIRIS-REx Visible and Infrared Spectrometer ...

6

That's a one trillion dollars question! Proximity of near-Earth flybys of asteroids is largely irrelevant when it comes to feasibility of matching their orbit and rendezvousing with them, what is more important is their hyperbolic excess velocity with respect to Earth, and how much delta-v is needed to do that. There are many Athen, Apollo and Amor groups of ...

5

Dangerous asteroids are those that can hit the Earth, and are large enough to cause substantial damage. There are currently no such known asteroids. (2020-02-21) There are two ways an asteroid could end up as considered dangerous: We discover it. There may be an asteroid bound for Earth at this moment, we just haven't seen it yet. This is fairly straight ...

5

The real issue here is how much rocket propellant you have to spend to get to the location in question. In one way, asteroids are easier to get to due to the fact that landing on the Moon takes a lot of velocity change. On the other hand, an asteroid flying through the Earth-Moon system is going really fast, so catching up with it is going to take a lot of ...

5

Safety of our blue planet. Eventually, gravity anomalies would cause even a perfectly orbited object (a moonlet?) to preces and hit the body it orbits around. Since orbiting an asteroid means reducing large fraction of its momentum to bring it closer to celestials it naturally orbits (NASA's plans involve capturing a near-Earth asteroid, or NEO, as part of ...

5

To add to the other answers, Wikipedia has another page listing objects at Lagrangian points, and for Sun–Earth L4 (SEL4) it currently lists: Asteroid 2010 TK7 is the first discovered "tadpole" orbit companion to Earth, orbiting L4 with a mean distance of about one astronomical unit. STEREO A (Solar TErrestrial RElations Observatory – Ahead) made ...

4

The threat posed by such near-Earth objects can be illustrated by the most famous extinction-level asteroid, the one responsible for the Chixclub crater of the Yucatán Peninsula. This bolide, at least 10 km wide, is almost universally credited with the demise of the dinosaurs. Defensive measures against such objects entirely depends upon finding it in time ...

4

Your encounter must by definition occur somewhere around the MOID line, if you do not consider to significantly change the trajectory. A solution can be obtained using Keplerian analysis, but that is only an approximation, due to the hard-to-restrict three body nature of the problem. If I understand your question correctly, you want a higher degree of ...

3

There are estimated to be around 1 million Near Earth Objects (NEOs) of around in the same size as 2017 VL2, of which around 1% are known (see Rusty's Planetary Defense 6-part series). It's only much larger asteroids which are better tracked: we're estimated to know well over 90% of the NEOs larger than 1 km, and are aiming to get up to 90% of the 140 m+ ...

3

We want to find NEOs that are inside Earth's orbit, like Atens, and telescopes don't like looking close to the Sun. So the more inside the orbit of the Earth you can get, the more new NEOs you will find without having to look at the Sun. Ideally you'd like a NEOCAM near the orbit of Venus. Then you'd be able to catch 'em all. But at E-S L1, you'll find most ...

3

Possibly the earliest documented mini-moon was the one associated with the 1913 Great Meteor Procession. After 2006 RH120, that you mentioned, another was identified on October 3, 2015 and designated WT1190F. It impacted Earth on November 13, 2015. It was probably space debris, and not natural. There's only one other potential candidate that I know of so ...

3

The trick isn't to mine them when they are close, necessarily. Asteroids are cheaper to get to than the Moon because the Moon has quite a bit of gravity. If you aim correctly, you can avoid all of the loss of rocket fuel associated with gravity. Where it is doesn't matter that much (So long as it is in a nearby orbit. The bottom line is, an Asteroid mining ...

2

There is a large amount of dust, and one known asteroid. From Wikipedia: The Sun–Earth L4 and L5 points lie 60° ahead of and 60° behind the Earth as it orbits the Sun. The regions around these points contain interplanetary dust and at least one asteroid, 2010 TK7, detected October 2010 by WISE and announced July 2011. The Earth–Moon L4 and L5 ...

2

Multiple reasons exist. Weapon of Mass Destruction Any large body in orbit is a potential weapon of mass destruction. Drop a 20-ton rock from orbit, and it may not survive, but if you do it right, it creates a crater some 100m across. While NASA is not planning on using deadfall ortillery, the possibility is a political issue. Ownership and access ...

2

These objects aren't of particular interest at the moment, as we would have a hard enough time reaching Near Earth asteroids. However, they offer some potential benefits in the future, namely: They could provide orbital resources for Mars for fuel and such. They could assist in transforming Mars (Impacts could provide useful resources, for instance.) ...

2

WT1190F orbited the Earth during the time it was observed. There were a number of varying observations that were made over it's lifetime. Wikipedia shows the lifetime at 3 different years, each with a wildly different orbit. Due to frequent passes by the Moon, as well as the Yarkovsky effect and pertubations of solar radiation, even a small difference could ...

1

Wikipedia covers this. The 1 in 1410 probability comes from Long-term impact risk for (101955) 1999 RQ36 in 2009 which notes... The analysis of impact possibilities so far in the future is strongly dependent on the action of the Yarkovsky effect, which raises new challenges in the careful assessment of longer term impact hazards. With better ...

1

Monostatic just means the transmitter and receiver are in the same place (DSS-14), as opposed to bistatic radar where they are separate (DSS-13 transmitter, Green Bank receiver). No klystron means they don't have a functioning radar transmitter. DSS-13 will be used as the transmitter, while Green Bank will receive the radar echo. Monostatic radar requires a ...

1

In theory, a smaller telescope can see a dim object by just looking longer than a larger one. There are issues of noise and stability that limit this, but for small factors it works. So their plan seems to be to break up a large-telescope observing plan into plans for longer observations with multiple smaller telescopes. This (somehow) saves lots of cost. ...

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According to this paper, it is unlikely: Hanno Reis, Daniel Tamayo, David Vokrouhlicky. The random walk of cars and their collision probabilities with planets. arXiv:1802.04718: By running a large ensemble of simulations with slightly perturbed initial conditions, we estimate the probability of a collision with Earth and Venus over the next one million ...

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The error IndexError: tuple index out of range is simply because I mistyped the two indexes in the error message in that source file. Python is zero-indexes so I ought to have typed: IOError('cannot get {0} because {1}'.format(url, e)) Instead, as you can see, I seem to have produced the utterly wrong: IOError('cannot get {1} because {2}'.format(url, e)) ...

1

Asteroid TX 68 2013 will pass near the earth on March 5 , 2016

1

Although the universe does revolve around me, I'm assuming you meant the barycentric celestial reference system :) HORIZONS will give you these elements if you use these settings:

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A practical way to deflect large asteroids could be kinetic impact with a smaller asteroid. That smaller asteroid would in turn be deflected to collide with the larger asteroid using either a spacecraft that landed on it and used e.g. ion thrusters, or it could be done via a kinetic impact using a yet smaller asteroid. In the latter case, the accuracy of ...

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