It would be disappointing, to say the least, to travel ten million kilometers only to find it's space flotsam.
1) the orbit is locked into a very odd figure-8 pattern that does not seem realistic to be either an artificial satellite launched from Earth or a natural satellite of Earth or asteroid. Taking into consideration [all of the] gravitation and solar forces on the object, this orbital pattern is about as strange as has ever been seen.
2) The mass of the object is very low, and indicates that it is NOT natural "space rock" material, very small for its total volume and size.
further complicatiing things is that the orbit of this unknown object is fairly stable and not subject to orbital "decay" as one would expect from something launched from Earth.
Is it possible that this object could eventually be shepherded into a more stable orbit around the Earth, not by artificial means but just the Earth's gravitational influence, so it becomes a true satellite.
If this asteroid turns out to be a valuable resource type, it might be a candidate for more ambitious missions to actually gradually move the entire thing to a more convenient location in earth-moon Lagrange or lunar orbit.
I bet Planetary Resources has been looking at this one for awhile already.
Its a cool discovery. It would be interesting to know if there are realistic trajectories to reach it with a manned mission (e.g., with Orion or Dragon 2). Given its substantial inclination, I can imagine that there might be other objects which are more accessible in terms of delta-v. Quote1) the orbit is locked into a very odd figure-8 pattern that does not seem realistic to be either an artificial satellite launched from Earth or a natural satellite of Earth or asteroid. Taking into consideration [all of the] gravitation and solar forces on the object, this orbital pattern is about as strange as has ever been seen. Strange claim. This "figure 8 pattern" is only a projection of the orbit onto the Earth's night sky. If you look at the video in the OP link, its a perfectly normal elliptical orbit around the sun. It just happens to be one slightly perturbed by the Earth in a way such that it keeps the Earth company.Quote2) The mass of the object is very low, and indicates that it is NOT natural "space rock" material, very small for its total volume and size. Even more strange claim. I strongly doubt anyone has been able to measure the mass of this object.Quotefurther complicatiing things is that the orbit of this unknown object is fairly stable and not subject to orbital "decay" as one would expect from something launched from Earth.Orbital decay (for satellites) is not a consequence of having been launched from Earth. Its a function of the number of atoms (from the extended atmosphere) encountered by a satellite on its orbital path, and the resulting "drag" force slowing it down. This effect (which applies to natural and artificial objects equally, of course) is important for the first 1000 km or so, and negligible on human time-scales above that. As this new asteroid is even further away than that (way beyond the Moon's orbit), this is a complete non-issue here. QuoteIs it possible that this object could eventually be shepherded into a more stable orbit around the Earth, not by artificial means but just the Earth's gravitational influence, so it becomes a true satellite.It would need to shed some orbital energy for that. Its not impossible, considering e.g. scenarios involving repeated swing-bys with the Moon, but its not very likely. Exemplified by the fact that neither the Earth, nor the other terrestrial planets seem to have such "captured" small satellites.QuoteIf this asteroid turns out to be a valuable resource type, it might be a candidate for more ambitious missions to actually gradually move the entire thing to a more convenient location in earth-moon Lagrange or lunar orbit.At 40-100 m, its likely to be not worth the effort. Perhaps for fuel, if its volatile-rich, or rare metals, if its an iron. Both are relatively unlikely, at ca. 15% and ca. 2%, respectively. Of course, its viability as a resource will also depend on the delta-v needed to reach it. QuoteI bet Planetary Resources has been looking at this one for awhile already.It has only been discovered in April this year. I doubt PR knew about it before anyone else.
I thought Mars's moons were captured asteroids from the asteroid belt?
Also will this object be given a proper name being as it is a semi-satellite of Earth now and for a number of centuries beyond?
Quote from: Comga on 06/16/2016 09:49 pmIt would be disappointing, to say the least, to travel ten million kilometers only to find it's space flotsam.Unless it's flotsam that's not human-made. :-)
Its a cool discovery. It would be interesting to know if there are realistic trajectories to reach it with a manned mission (e.g., with Orion or Dragon 2). Given its substantial inclination, I can imagine that there might be other objects which are more accessible in terms of delta-v. ...
While it's likely to be some natural object, the forces involved in its' orbit, seem to make that highly unlikely to be of natural origin.
Regarding delta-v and accessibility, there are certainly others with better specific launch opportunities, but in terms of total viable opportunities it's pretty high on the list. NHATS shows a large number of viable round-trips for <7km/s from LEO to re-entry, with the lowest energy ones taking about a year.
Spectral and other data will tell if it's a particularly interesting object or not, and improve size constraints if they can get the right IR data - and perhaps radar can tell if it has companions (which would allow one to determine its mass; I'm not sure why it's shown as not observable from Goldstone or Arecibo, since it reaches a decent declination and pointing uncertainty is low) - but for flexibility and ease of targeting it may be quite attractive.
At a size of between 130 to 325 feet, It'd be a pretty safe bet that it ain't one of ours.
Quote from: JasonAW3 on 06/17/2016 01:46 pmAt a size of between 130 to 325 feet, It'd be a pretty safe bet that it ain't one of ours.I'll bet that size is based largely on brightness, though. If's painted white, it's probably smaller than the typical asteroid of similar brightness.
Again, likely a rock, but a pretty weird one.
Does anyone know how the size was determined? Most size calculations use the measured brightness with an assumed albedo, like Proponent said.
I am further confused on this issue when I read in a couple of articles reporting this news that the Earth already has a number of mini-moons, but it was stated up thread that the rocky planets don't collect such moons?
Quote from: Bynaus on 06/17/2016 06:18 amIts a cool discovery. It would be interesting to know if there are realistic trajectories to reach it with a manned mission (e.g., with Orion or Dragon 2). Given its substantial inclination, I can imagine that there might be other objects which are more accessible in terms of delta-v. ...First, thanks Bynaus for all your insightful comments, they are spot on about about what is known about this item.Regarding delta-v and accessibility, there are certainly others with better specific launch opportunities, but in terms of total viable opportunities it's pretty high on the list. NHATS shows a large number of viable round-trips for <7km/s from LEO to re-entry, with the lowest energy ones taking about a year. It can be done even quicker, coming down to <200 days if you can come up with 11+ km/s. What's pretty unique about this due to its quasi-stable relationship with earth is that the windows are open very consistently, for many years, rather than every few years or more as for other low delta-V NEOs. Spectral and other data will tell if it's a particularly interesting object or not, and improve size constraints if they can get the right IR data - and perhaps radar can tell if it has companions (which would allow one to determine its mass; I'm not sure why it's shown as not observable from Goldstone or Arecibo, since it reaches a decent declination and pointing uncertainty is low) - but for flexibility and ease of targeting it may be quite attractive.
What sort of image could we expect from Hubble of this object? Cheers, Martin
Even more strange claim. I strongly doubt anyone has been able to measure the mass of this object.
Quote from: Bynaus on 06/17/2016 06:18 amEven more strange claim. I strongly doubt anyone has been able to measure the mass of this object.Of course they have.http://www.scientificamerican.com/article/how-do-scientists-measure/ - Ed Kyle
Quote from: edkyle99 on 06/18/2016 01:06 pmQuote from: Bynaus on 06/17/2016 06:18 amEven more strange claim. I strongly doubt anyone has been able to measure the mass of this object.Of course they have.http://www.scientificamerican.com/article/how-do-scientists-measure/ - Ed KyleThe OP was asking about THIS object, and since we haven't had a spacecraft near it, there's nothing for it to perturb gravitationally to get a mass. What you'd do is figure a few 1000 kg/m^3 density, give a factor of 2 uncertainty (mostly on the low side in case it's like Mathilde). Given the uncertainty in the size, there's probably about a factor of 10 uncertainty in mass right now. I suspect the size can be measured pretty accurately by radar from the intensity of a reflected signal.Given that Congress seems to want to kill ARRM, it would probably be more useful to think of a low-cost way to get a probe to the asteroid. The Japanese Procyon would likely be a good departure point for a design, but of course its SEP failure would have to be diagnosed and remedied.
Quote from: MP99 on 06/18/2016 11:35 amWhat sort of image could we expect from Hubble of this object? Cheers, MartinA dot. Resolution of Hubble at that distance should be 5 km for violet/soft UV wavelengths.
Quote from: jgoldader on 06/18/2016 02:06 pmThe OP was asking about THIS object, and since we haven't had a spacecraft near it, there's nothing for it to perturb gravitationally to get a mass. What you'd do is figure a few 1000 kg/m^3 density, give a factor of 2 uncertainty (mostly on the low side in case it's like Mathilde). Given the uncertainty in the size, there's probably about a factor of 10 uncertainty in mass right now. I suspect the size can be measured pretty accurately by radar from the intensity of a reflected signal.If the orbit is known, the mass is known. - Ed Kyle
The OP was asking about THIS object, and since we haven't had a spacecraft near it, there's nothing for it to perturb gravitationally to get a mass. What you'd do is figure a few 1000 kg/m^3 density, give a factor of 2 uncertainty (mostly on the low side in case it's like Mathilde). Given the uncertainty in the size, there's probably about a factor of 10 uncertainty in mass right now. I suspect the size can be measured pretty accurately by radar from the intensity of a reflected signal.
Quote from: Nilof on 06/18/2016 12:14 pmQuote from: MP99 on 06/18/2016 11:35 amWhat sort of image could we expect from Hubble of this object? Cheers, MartinA dot. Resolution of Hubble at that distance should be 5 km for violet/soft UV wavelengths.What sort of image could we expect from JWST of this object?
How the sizes of asteroids too small to resolve are estimated:http://www.nasa.gov/mission_pages/WISE/multimedia/gallery/neowise/pia14733.html
Quote from: Donosauro on 06/18/2016 07:56 pmHow the sizes of asteroids too small to resolve are estimated:http://www.nasa.gov/mission_pages/WISE/multimedia/gallery/neowise/pia14733.htmlIt's really faint.Which telescopes could observe 2016 HO3 in the thermal infrared?WISE is no longer doing thermal infrared observations, and it is not clear that 2016 HO3 ever went across WISE's line of sight, given the odd orbit, or that it could be seen by WISE. (Wise expanded the population of <1km NEOs, but how many <0.1 km NEOs did it find?)Does it get far enough from the Sun to allow JWST to look at it, when JWST launches and IF observing 2016 HO3 successfully competed for observing time?
Perhaps this could be suitable for a BEO cubesat mission. Duration should be reasonably short, distance for communicating back is fairly low. No issue with distance from the Sun for solar panels. Flyby would give useful info, and might not have to be at huge speed (depending on SC lifetime). Cheers, Martin
Quote from: dror on 06/18/2016 06:05 pmQuote from: Nilof on 06/18/2016 12:14 pmQuote from: MP99 on 06/18/2016 11:35 amWhat sort of image could we expect from Hubble of this object? Cheers, MartinA dot. Resolution of Hubble at that distance should be 5 km for violet/soft UV wavelengths.What sort of image could we expect from JWST of this object?JWST is bigger, but it's also restricted to longer wavelengths so its maximum resolution should still be >4 km. You'd need a diffraction limited telescope with a 100m main mirror (or an interferometer with a baseline of that magnitude) to resolve this asteroid. For pretty pictures, sending something close to it is the only real option....
Quote from: MP99 on 06/18/2016 09:00 pmPerhaps this could be suitable for a BEO cubesat mission. Duration should be reasonably short, distance for communicating back is fairly low. No issue with distance from the Sun for solar panels. Flyby would give useful info, and might not have to be at huge speed (depending on SC lifetime). Cheers, MartinA big problem is propulsionIt is safe to assume that the delta-V in the NHATS models is equally distributed among the three.That means the flyby needs ~2.5 km/sec.That's a lot of propulsionCubesats rarely have any, and none have had 1% of this. And you know the tyranny of the rocket equation.And no cubesats have had high Isp SEP.
Quote from: Nilof on 06/18/2016 07:05 pmQuote from: dror on 06/18/2016 06:05 pmQuote from: Nilof on 06/18/2016 12:14 pmQuote from: MP99 on 06/18/2016 11:35 amWhat sort of image could we expect from Hubble of this object? Cheers, MartinA dot. Resolution of Hubble at that distance should be 5 km for violet/soft UV wavelengths.What sort of image could we expect from JWST of this object?JWST is bigger, but it's also restricted to longer wavelengths so its maximum resolution should still be >4 km. You'd need a diffraction limited telescope with a 100m main mirror (or an interferometer with a baseline of that magnitude) to resolve this asteroid. For pretty pictures, sending something close to it is the only real option.......so I wonder if any of these would work for resolving the size:https://en.wikipedia.org/wiki/List_of_astronomical_interferometers_at_visible_and_infrared_wavelengths...what's the apparent magnitude of 2016 HO3?
Quote from: Robotbeat on 06/19/2016 02:25 amQuote from: Nilof on 06/18/2016 07:05 pmQuote from: dror on 06/18/2016 06:05 pmQuote from: Nilof on 06/18/2016 12:14 pmQuote from: MP99 on 06/18/2016 11:35 amWhat sort of image could we expect from Hubble of this object? Cheers, MartinA dot. Resolution of Hubble at that distance should be 5 km for violet/soft UV wavelengths.What sort of image could we expect from JWST of this object?JWST is bigger, but it's also restricted to longer wavelengths so its maximum resolution should still be >4 km. You'd need a diffraction limited telescope with a 100m main mirror (or an interferometer with a baseline of that magnitude) to resolve this asteroid. For pretty pictures, sending something close to it is the only real option.......so I wonder if any of these would work for resolving the size:https://en.wikipedia.org/wiki/List_of_astronomical_interferometers_at_visible_and_infrared_wavelengths...what's the apparent magnitude of 2016 HO3?Its apparent magnitude should be about 19 when the object is closest to earth, if I did the math right. So it looks like none of the existing interferometers are up to the task.
Currently no cubesats have high Isp SEP.However"With a ~2U package (including 300cc/1.5kg iodine propellant), the {BUSEK} BIT - 3 system can provide 3km/s delta-V to a 6U/12kg CubeSat."http://www.nasa.gov/sites/default/files/files/Vlad_Busek_Iodine_RF_Ion_Thruster.pdfThis is one of the thrusters in the Technology Development Project Selections announced on September 4, 2013. These should be available soon and in need of a mission (unless they were cancelled).http://www.nasa.gov/content/technology-development-project-selections/#.V2YKmDVaHIV
The fact that the solar wind doesn't perturb it much (hundreds of years stability) suggests a high density.
Since it is close for such a body
As to how you'd get something into such an orbit, it would likely be from debris from the Earth or Moon, either from formation or as part of a collision, where such escaped but not by much, and by accident entered a weak stability region between the Earth Moon Sun ensemble, staying there ever since.
The most interesting part of this is "how long" has it been there? During the formation of the solar system, much has been swept away, so if it has been there a long time, why wasn't it dislodged?
Magnitude per JPL Horizons won't get brighter than recently, in the near future won't get brighter than ~22nd mag. Might change with better obs but going on prior results it's hard to find. See attached for plot of predicted mag and distance. Later it gets closer again but phase angle is worse.
the orbit is locked into a very odd figure-8 pattern that does not seem realistic to be either an artificial satellite launched from Earth or a natural satellite of Earth or asteroid. Taking into consideration [all of the] gravitation and solar forces on the object, this orbital pattern is about as strange as has ever been seen.
Quote from: Comga on 06/16/2016 09:49 pmthe orbit is locked into a very odd figure-8 pattern that does not seem realistic to be either an artificial satellite launched from Earth or a natural satellite of Earth or asteroid. Taking into consideration [all of the] gravitation and solar forces on the object, this orbital pattern is about as strange as has ever been seen. Thought you all might like a link to the original source of this. It's a very strange orbit indeed. Always roughly in the direction of Leo / Virgo, in a figure of eight orbit as seen from Earth - so sometimes closer to the sun, sometimes further away but always in roughly the same absolute direction from Earth. It's very accessible from Earth, in terms of delta v anyway if not bothered about the duration - seems to be slightly easier to reach than the EML2 for its minimum energy orbit and slightlier easier to reach than the Moon for the minimal duration orbit. See delta v table
As to visiting it, a lunar encounter with a phased entry into the same gravitational equipotential would be the obvious choice, like entering a Lissajous orbit. If your US were long lived enough for a post lunar burn you could save much time (down to a few months), but if we're being economical, a hundred kilogram SEP craft that shared a GTO-1800 ride as a secondary might make it in a few years or less, depending on launch and if you could coax a third burn post primary payload, and the moon's position. Such a mission would take longer to design/fund/build/launch then to fly
Quote from: jgoldader on 06/18/2016 02:06 pmQuote from: edkyle99 on 06/18/2016 01:06 pmQuote from: Bynaus on 06/17/2016 06:18 amEven more strange claim. I strongly doubt anyone has been able to measure the mass of this object.Of course they have.http://www.scientificamerican.com/article/how-do-scientists-measure/ - Ed KyleThe OP was asking about THIS object, and since we haven't had a spacecraft near it, there's nothing for it to perturb gravitationally to get a mass. What you'd do is figure a few 1000 kg/m^3 density, give a factor of 2 uncertainty (mostly on the low side in case it's like Mathilde). Given the uncertainty in the size, there's probably about a factor of 10 uncertainty in mass right now. I suspect the size can be measured pretty accurately by radar from the intensity of a reflected signal.Given that Congress seems to want to kill ARRM, it would probably be more useful to think of a low-cost way to get a probe to the asteroid. The Japanese Procyon would likely be a good departure point for a design, but of course its SEP failure would have to be diagnosed and remedied.If the orbit is known, the mass is known. - Ed Kyle
Quote from: Space Ghost 1962 on 06/20/2016 12:07 amThe fact that the solar wind doesn't perturb it much (hundreds of years stability) suggests a high density.I had assumed that the hundreds of years was based on projecting back from current orbit. If it is low enough density to be perturbed, then that just seems to invalidate the assumption, IE it could be a man-made object that seems to be long term stable due to a fluke of current position.
25 - 113 meters:Estimated diameter in meters showing the minimum and maximum likely size based on assumed maximum and minimum albedos of 0.60 and 0.03, respectively. If the size is "known", a single value is shown instead. If a single value is shown, it should still be considered an estimate.
A cubesat definitely /could/ have high-Isp propulsion. Just because none have so far doesn't mean they couldn't.
Technology Development Project Selections announced on September 4, 2013. These should be available soon and in need of a mission (unless they were cancelled).http://www.nasa.gov/content/technology-development-project-selections/#.V2YKmDVaHIV
Quote from: Robotbeat on 06/23/2016 12:12 amA cubesat definitely /could/ have high-Isp propulsion. Just because none have so far doesn't mean they couldn't.CorrectA_M_Swallow reminded us of Busek's program to build high Isp engines for smallsats and cubesats. QuoteTechnology Development Project Selections announced on September 4, 2013. These should be available soon and in need of a mission (unless they were cancelled).http://www.nasa.gov/content/technology-development-project-selections/#.V2YKmDVaHIV
Quote from: Comga on 06/23/2016 12:32 amQuote from: Robotbeat on 06/23/2016 12:12 amA cubesat definitely /could/ have high-Isp propulsion. Just because none have so far doesn't mean they couldn't.CorrectA_M_Swallow reminded us of Busek's program to build high Isp engines for smallsats and cubesats. QuoteTechnology Development Project Selections announced on September 4, 2013. These should be available soon and in need of a mission (unless they were cancelled).http://www.nasa.gov/content/technology-development-project-selections/#.V2YKmDVaHIV The challenge with high Isp cubesat propulsion is that cubesats tend to be very power limited, which means they probably optimize out to a lower Isp than a bigger satellite would (and they already typically optimize out to far lower Isp than ion engines are capable of). ~Jon
The challenge with high Isp cubesat propulsion is that cubesats tend to be very power limited, which means they probably optimize out to a lower Isp than a bigger satellite would (and they already typically optimize out to far lower Isp than ion engines are capable of).
Quote from: jongoff on 06/23/2016 04:33 amThe challenge with high Isp cubesat propulsion is that cubesats tend to be very power limited, which means they probably optimize out to a lower Isp than a bigger satellite would (and they already typically optimize out to far lower Isp than ion engines are capable of). By power limited do you mean power/mass? I would have thought there was a scaling problem in the other direction for solar power/mass. (im not claiming any experience, just laymans logic)
He means straight forward power limited. Cubesats have small solar panels so it unlikely to have more than 50-100 watts of power. About the same as the lamp in my lounge used to use.
If 2016 HO3 is in fact a natural 40-100m asteroid (likely) and if it also proves to be type with valuable resources either metallic or carbon (based on an exploration mission), how practical would it be to move it to a more useful location to be exploited? What would be required? Where would you move it?
You would think that some at NASA would be jumping at the chance to send a Pioneer class probe to H03 ASAP, since that would be a great target for the Asteroid mission.
The ConstantQ™ thrusters will be used on the CubeQuest competition’s Miles spacecraft. This craft features 12 thrusters with a custom tank design, taking the craft to lunar orbit and to asteroid 2016 HO3.....The ConstantQ™ is a hybrid electrostatic thruster, featuring an exceptionally compact and power-efficient design with a self-neutralizing plasma flow. The thruster gives 1.25 mN of thrust (modes up to 2.4mN available), 760 sec Isp (modes over 3,500 sec available), at 5.5 Watts total input power (3W beam power) when tested in Argon. Our “Model H” system includes 4 thruster heads, high voltage electronics, and 1kg of solid Iodine in a 1.5kg total, 0.5U, 22W package, giving a 8kg 6U satellite 995 m/s delta-v. The Model H’s thrusters are canted allowing for both primary propulsion and attitude control without use of moving parts – an important factor in mission assurance.
Quote from: Danderman on 08/05/2016 06:43 pmYou would think that some at NASA would be jumping at the chance to send a Pioneer class probe to H03 ASAP, since that would be a great target for the Asteroid mission.It's not a great target for the Asteroid redirect mission. See my post above.
Why not Dragon asteroid 2017 as a Mars mission precursor!?
Quote from: Geron on 06/18/2016 02:09 pmWhy not Dragon asteroid 2017 as a Mars mission precursor!?because people who become Mars obsessed aren't into rocks
Quote from: bad_astra on 09/05/2016 08:26 pmQuote from: Geron on 06/18/2016 02:09 pmWhy not Dragon asteroid 2017 as a Mars mission precursor!?because people who become Mars obsessed aren't into rocksAlso, since the goal is Mars and the primary difficulty there (the problem which must be solved no matter the other details, and which must be solved to start major even robotic preparations) is EDL, why spend the money on a launch to a rock that isn't testing EDL?If it's deep space operational experience and high speed reentry you want to test, a loop around the Moon would work, too, and would be faster.
There's a good reason for anyone wanting to colonize mars to take an interest in asteroids first, namely Phobos. You couldn't ask for a better way-station for Mars, for more reasons than I will go into here. Phobos makes doing Mars easier. And if you want to size up opreations on Phobos while getting to know it better why not pick the easiest NEO you can find as a test.