Any serious plans to send a probe into the Sun to explore its depths as far as possible?
What would help a probe last as long as it could and how deep could it get?
Could it even radio or laser out any data?
What about a Sun skimmer?
I don't know, but my best guess would be <poof!!!> before any such probe even got close to the photosphere, so I doubt that any useful data could be gathered even if it could somehow be transmitted through all that RF noise... (need shades just to think about it!!!)
Solar Probe was supposed to come within 3 solar radii.
I suppose an elaborately shaded craft could get pretty close. A "ball" with instruments could be surrounded with a hemispherical shade with near 100% reflectance held by struts rather far from the craft. Perhaps even a hierarchical tier of such shades could perform even better.
Entering the photosphere would instantly annihilate any craft. The velocity of the craft as it hit the outer layers of gas, which would increase rapidly in pressure with depth, would be colossal -- even aside from the radiative heat.
Well, there's always David Brin's solution. Use a laser to *refrigerate* the probe, and to provide braking thrust against the Sun's gravity.
The idea is to drain the thermal energy into a system that powers a very powerful, very HOT laser. This would be the *only* way to use a "radiator" to shed heat into the photosphere.
A side benefit would be that such a laser would exert *significant* thrust, and it would be aimed at a target that it couldn't much hurt -- the Sun's surface.
The catch, of course, is that we really don't have the technology to build such a hot laser, or to convert the heat we can't reflect away into power for the laser. Once we develop those technologies (if we ever do), then a solar probe is more feasible...
-the other Doug
Other ways to probe the Sun would be sending a laser ray or radio beam. Unfortunately, the Sun is opaque to both. At best we can imagine passing very close to the surface (from a probe to the Earth). We can imagine to send very low radio frequencies, but I am afraid that the time constants involved would be thousands of years. (Already on Earth probing the core with radio waves would require frequencies too low to be actualy useable).
Impossible, impossible, impossible...
So why not the most impossible of all: SUN SAMPLE RETURN MISSION!!!!
Ouah nutter and nutter!!
But paradoxically it is the simplest to do, and it was even already done, with this probe, I did not remember the name, perhaps Stardust, which went in space to capture solar wind dust, and then crashed at time of return on Earth, but all the same produed useable samples of Sun composition.
But they took no measure against contamination of Earth by Sun life form...
The only "practical" solution I can see would be to embed a probe and several layers of redundant sensors at the dead center of a rather large comet nucleus or maybe one of Saturn's smaller icy moons and deorbit the whole thing right into the Sun using a lot of ion thrusters or perhaps mass drivers, if there was enough metallic material available to use as reaction mass...
I doubt that the value of data retrieved would ever equal the investment, though, even if all the assumed supporting technologies were ever available. Remote sensing is far better in all respects!
A lot of neutrinos from the interior of the Sun is passing through Earth all the time, so all we need to see into the Sun is a good neutrino telescope.
tty
Richard Trigaux, alas, is too optimistic about the Genesis scientists being able to retrieve "most" of their planned data. The latest news is that they will indeed be able to properly measure the amount of noble gases in the Sun, since those (except for argon-40, which is irrelevant) exist only in microscopic amounts in Earth's atmosphere and water, and so weren't affected by the crash's contamination. But that was only their third scientific priority -- the top ones were to measure the isotopic ratios of the Sun's oxygen and nitrogen (especially the former), and unfortunately those have been very badly contaminated indeed. It's questionable whether they'll be able to retrieve any meaningful results on those.
As for Solar Probe -- whose design has been modestly changed lately, without harming its total science output -- see the very informative official Web page at http://solarprobe.gsfc.nasa.gov/ . Solar scientists would absolutely love to fly this mission, but it will cost as much as a New Frontiers mission and so NASA has yet even to officially propose it. (It's even been suggested that it should be included in the New Frontiers program. But that, in turn raises the question of whether ALL competitive-proposal programs for space science -- Solar System, Mars, astronomy, magnetospheric science or what have you -- that are in the same cost range should be folded up together into a single competitive space-science proposal program, which might well make sense.)
There is no doubt at all, however, that we can make Solar Probe work -- amazingly, we already have almost all the technology we need for it. Extensive ground tests of that dunce-cap shaped carbon heat shield show that not only does it provide full protection against the heat, but it vaporizes considerably less than expected and so won't contaminate the probe's plasma measurements. The only thing that requires any additional work at this point is the design for the "plasma periscope" that would peep around the edge of the heat shield and divert a small amount of the outflowing solar plasma to the analyzers behind the shield.
Unfortunately, the Solar Probe mission, or whatever it's name of the year is... has seemed to always be 10 years in the future. Rather like "Main Belt Multi Asteroid Rendezvous", which has been repeat-studied and repeat-proposed since the early 70's. If <whimper> Dawn flies, we'll finally get that one.
It would be possible to create a probe that could reach the photosphere, and continue into the body of the Sun a short way. There is a lot of question as to how it might communicate out of the Sun. Communication might be possible with x-ray lasers. Anything with a lower photon energy might get absorbed pretty quickly by the plasma.
This is not a realistic plan for the short term future, but you can imagine a craft that has a mass of billions of tons, and has a mechanism for spraying an opaque cloud out in front of it to shield the vessel with disposable shielding. Alternatively, or in addition, you might have a conveyer belt of rigid shielding that only exposes the individual tiles to the Sun for a small fraction of the time. Excess heat is blown off in the opaque jets previously described, or used to heat gases to thrust out the back.
The Photosphere's density is very low. It would take quite a while for a billion ton object to be vaporized if it was well designed. Just as a wild guess, such a craft could potentially descend a thousand miles.
The trouble is that we haven't as yet come up with a way to collect and store it that's even remotely as efficient as utilizing -- at breakneck pace -- the fossil fuels that Mother Nature thoughtfully spent hundreds of millions of years accumulating for us. Talk about spendthrift heirs!
As for solar astronomy missions -- including Solar Probe -- they may have genuine practical importance. We need to know more about the Sun's longer-term activity cycles, in order to judge what effects those will have on Earth's climate that will be overlaid on top of the effects from the buildup of man-made greenhouse gases.
And, yep, the idea of Solar Probe has been around for a long, long time. Back in the early 1980s it was a big hulking thing called Starprobe that weighed thousands of kg and would have had to be launched by a Titan. Then, in the early 1990s, someone developed a way of greatly shrinking it by shaping the heat shield in such a way that it doubled as the probe's high-gain antenna. Still later, however, it became clear that electronic miniaturization has advanced to the point that we don't need that peculiar idea to build a lightweight version of Solar Probe. As with ion drives, We Have The Technology, and the only thing stopping us from doing it is the cost.
And Congress itself has repeatedly expressed some interest in this mission, and at least twice has inserted an additional $10 million into NASA's budget -- which NASA hadn't asked for -- for design studies. At some point, it WILL fly. (The analogy that comes to mind is SIRTF, which got delayed repeatedly, but in the process underwent technological evolution that both drastically reduced its cost AND increased its science output. And finally, it did fly, as the extremely successful Spitzer Space Telescope.)
One of the more mind-boggling things about this mission, by the way, is that one of its goals is to take images of the solar corona -- from inside the corona, looking out.
Well, if one gets to think into the really long-range future (think decades), then a Solar Sample Return mission from the corona (or even the photosphere, if you want to get REALLY fanciful) might finally find a use for Bussard's beautiful yet cosmically inefficient ramjet.
Use electromagnetic fields to collect hydrogen from the corona to fuel a fusion rocket, in order to collect samples and fly back to Earth. It'd be a project of stunning magnitude-thousands of tonnes, probably-but what's a few billion to a thought experiment?
(Sigh)
You're all missing the obvious way to design a Solar Probe, although ISA already described a most persuasive mission scenario.
Just build one and launch it at night!
(Ducks and runs!)
Bob Shaw
A limitless, though relatively small, source of energy is the mouth-flapping of "zero-point energy" and the like folks. Considerably more abundant is the hot-air from politicians and we-know-what's-best-for-you advocates.
I recall a sci fi story from long ago about a manned station and manned boats on the surface of the sun. The three main obstacles to operating on the surface of the sun are:
1) intense heat
2) no solid surface
3) 32G surface gravity
The solutions are as follows
1) Carry a large supply of carbon, and pump it out of the surface of your platform. The carbon vaporizes and carries off the heat. Use carbon since it has the highest known melting and vaporization temperature of any substance. It acts like an ablative heat shield, or as the story described it, the bottom layer of a water drop in a hot pan.
2) Carry a big particle accelerator torus, and put a bunch of plasma in it and run it around the right direction such that it generates a magnetic field counter to the sun's magnetic field. If it is strong enough and controlled well enough, it will support the platform
3) Put this torus on the roof of the platform. Run the torus fast enough that through special relativity it gains enough mass to generate a 31G field in the up direction.
In the story, the mission of the platform and boats was to induce precisely controlled solar flares which would impact the atmosphere of the Earth, and in this manner they could control the weather. There was a vast representative democracy back on Earth, the Weather Congress, to decide what weather to have. There was a vast scientific institue, the Weather Advisors, to figure out how to implement the decisions of the Weather Congress. And there was the Weather Service, manning the base and boats on the sun, to carry out the plans of the Weather Advisors.
Now I know that there are dozens of reasons why the solutions proposed could not work (Where does all the carbon come from? What is the power source? What about tides from the gravity generator? Can you really use a plasma torus like that? The photosphere is hundreds of miles thick. Solar flares can't really influence Earth's weather that much. Even an enormous nuke is a mere sparkler on the sun, flares can't be induced.) but it is still interesting that someone actually considered a solution for landing on the sun which doesn't involve landing at night.
That story was Theodore Taylor's "The Weather Man". Interesting idea, but even at age 12 it struck me as being a wee bit implausible. (He later wrote a sequel involving a suicidal trip to the CENTER of the Sun to stop an instability therein.)
PINK FLOYD
SET THE CONTROL FOR THE HEART OF THE SUN
So THAT'S how they got so pink.
By the way, Solar Probe originally started out as one of that very unlikely trinity of missions that were set up under Goldin's tenure to supposedly develop the new technologies necessary to go to "the most difficult destinations in the Solar System" -- along with Europa Orbiter and the Pluto flyby. This program was commonly called "Fire & Ice", but had the awkward official name of "Outer Planets/Solar Probe". (Back in 1999 I wrote to Chris Chyba suggesting that it needed a better name, and proposing -- roll of drums -- "New Frontier". He was noncommittal. Alan Stern later told me that he'd considered that name for New Horizons, but decided that the JFK reference might make Bush even more hostile to the probe than he then was -- only to have O'Keefe later give that name to the entire middle-price planetary-probe program.)
Anyway, the idea -- which in retrospect seems utterly cockamamie -- was to connect these three utterly different missions by using the same "core spacecraft" for each of them. Goldin then decided to make things even worse by overriding the recommendation of COMPLEX that the Pluto probe -- which, unlike the other two, actually required NO new technology -- fly first in 2003; he ordered instead that Europa Orbiter be flown before the Pluto mission. The result, naturally, was to delay the Pluto mission further and further as the impracticality of doing Europa Orbiter any time in the near future became obvious -- but I was told at the October 2000 meeting of the Solar System Exploration Subcommittee that Goldin told an aide that he had actually done this (along with insisting on totally impractical super-miniaturization of the Pluto probe) as a subterfuge for getting rid of the Pluto mission altogether, on the grounds that "Nobody gives a damn about Pluto."
This is where, to my lasting amazement, I enter the story. I did an August 2000 piece for "SpaceDaily" proposing that not only did the Pluto mission not require any new technologies at all (unlike the other parts of OP/SP), but that it could be flown much more cheaply by simply mildly modifying the design of either of the two existing Discovery comet probes, Stardust and CONTOUR. A month later, NASA surprised everyone by suddenly putting out an AO for ideas for a cheap Pluto probe design -- which they made very clear they were doing extremely grudgingly, and with no desire to really fly the thing.
When I got to the SSES meeting in October, there were stacks of my article on the information table; and on the first day two guys from Lockheed Martin got up and presented the company's proposal for modifying "Stardust" for the Pluto mission -- which reflected my own suggestions down to the very last goddamn detail, except that the launch would not be possible before December 2004 and so required a bigger booster than my suggested November 2003 launch. They told me later that Lockmart had come up with the idea completely independently, which I believe -- it had not exactly been a hard idea for me to come up with. But, to my stupefaction, although I had come to that meeting just as a reporter, I discovered that in the process of asking the assembled scientists for information on various subjects I was also GIVING them some information, and so Michael Drake ended up letting me take a bigger role in the debate over Pluto than he was legally supposed to do. While there was universal agreement that the argument for a near-future Pluto/Kuiper flyby was overwhelmingly strong, on the last day there was a debate over whether they might "anger NASA" by recommending it, and I ended up giving them a mini-Agincourt speech to the effect that their official job was simply to recommend the best scientific strategy for flying planetary missions, that the Pluto mission was clearly part of this, and that if NASA turned it down anyway for non-scientific reasons the agency had no reason to blame them for recommending it.
Whether this made a difference or not, they DID very strongly advocate the mission in their report, and the scientific pressure for it simply got stronger and stronger, until we finally had the spectacle -- almost unprecedented at the time -- of the GOP Congress telling not only NASA but the White House itself to go a kite, and ordering inclusion of money for the mission in the NASA budget. (The 2002 Decadal Survey report forcefully recommending it was probably the last impetus necessary for this.)
I'm still trying to determine just how important my role in all this actually was; but it seems certain that Simon Mansfield (the editor of "SpaceDaily) and I had SOME effect. I later learned that NASA was actually shutting up any engineer or scientist from publicly proposing an economically designed Pluto mission by threatening to cut off their grants, and so Simon and I ended up innocently belling the cat by publicly proposing the idea for the very first time and thus making it impossible for NASA to hush up the idea any longer. This may or may not have been what forced it to put out that reluctant AO for ideas on just this subject a month later; but judging from my treatment at that SSES meeting a month after that, my article played at least some contributing role in getting NASA's planned cancellation of any Pluto flyby mission reversed.
New Horizons, of course, IS based on CONTOUR -- although much more loosely than its competitor "POSSI" was based on Stardust -- but I can't believe that I inspired that idea; there were surely engineers already thinking about it. But -- because, by pure dumb chance, Simon and I happened to be in exactly the right place at the right time -- I did play a role in getting it flown. I take for granted that I will never get the chance to do anything remotely as important for the rest of my life. (Not that I've quite given up the hope that someday lightning might strike twice -- although my recent plan to push a penetrator as a small piggyback lander for Europa Orbiter turned out to have a subtle but very important flaw in it pointed out at the recent COMPLEX meeting. Oh, well. Back to the drawing board.)
Anyway, in retrospect it's perfectly obvious that Europa Orbiter was the most complex of the three OP/SP missions and should therefore have been flown last, with the Pluto flyby going first and Solar Probe second. Thanks entirely to Crazy Dan Goldin, this didn't happen -- or we could have seen the Pluto mission launched, with considerably lower cost and more science return, in November 2003 (which would even have allowed it to do a very close Io flyby en route!) And Solar Probe is STILL a very important mission -- in terms of practical human benefit, maybe the most important of the three -- and badly needs to be flown.
Bruce:
Careful there Ted, or Crazy Dan might try to pull strings to have you nominated as the command pilot of a (briefly) manned Solar mission!
Of course, he'd stand every chance of getting the second seat reservation for himself...
...I wonder who'd get the third slot?
Bob Shaw
The Solar Probe project is still alive. In a Report released on July 4, 2007,
regarding their actions on NASA's FY 2008 budget, the Senate
Appropriations Committee states the following - "The Committee
has included an additional $20,000,000 for the Living With A Star Program
for the Solar Probe mission."
Another Phil
http://solarprobe.gsfc.nasa.gov/
If it actually gets funded, it should also give us a nice Jupiter bonus. I am not sure about imaging (perhaps it will have a navigation camera or be able to catch Jupiter and its moons in one of its cameras intended for the sun like STEREO did), but I can't imagine them passing up the chance to at least have a Ulysses-style encounter, given the fact that this mission will certainly have its fair share of particle and fields instruments.
Hey, my first post here.
So my idea for a solar probe involves a super long tethered probe, spinning at a rate so as to have it's surface velocity with respect to the Sun be close to zero. The "mothership" would be far enough away to endure the environment. I know, extremely long tether...
Another thought I had would be a "floater", i.e., a probe with enough surface area that it took advantage of the flux of light and other stuff to suspend itself at a distance above the surface. It'd be a way of lowering the geosynchronous orbit altitude way down, or generally lowering the speed of the orbit. I didn't see any other concepts taking advantage of solar sails to assist in reaching the Sun.
Maybe the floater and the tether could be combined.
What is the highest level of albedo that's been achieved with metals on Earth? If a shield had 100% reflectivity (impossible I know but theoretically), would that solve all heating problems, or does the albedo vary for different types of electromagnetic radiation?
From one reference on the web, I'm seeing that aluminum has an albedo of 73%.
Suppose that tungsten had the same albedo. By my calculations, a surface of tungsten, then, would melt if held in steady state at about 0.17 AU.
However, there are a lot of other tricks that could be played to help out. A thin foil of tungsten would only take solar radiation on one side while radiating it on the other. Halving the thermal load should allow an approach sqrt(2) closer.
The sunscreen on SP is a long cone that would be pointed towards the Sun. That spreads out the radiation that a disk would absorb over a much greater area. I don't see any theoretical limit to this approach, although the point at the very tip might be a failure point. There would have to be SOME surface perpendicular to the Sun.
I guess if a maniacal plunge sunward were attempted with the goal of approaching as near as possible, one strategy would be to have a series of sunscreens, each of which had enough separation from the main craft so as not to radiate much heat inward, with each one shaded until the one in front of it melted through. If the final plunge were fast enough (if, say, a gravity assist of Jupiter really whipped the thing into the Sun, with all of the acceleration that would come with that last neck of the Sun's gravity well), it might make a lot of progress in those final hours during which the screens were melting one after another.
I wonder what the engineering limit would be. The corona? The point where gas actually contributed measurable friction? Since such a craft could easily be set up for a free return to Earth, could we run a solar sample return?!? I'm not sure if there's much point doing it from close-up versus collecting the solar wind farther out, but it's an exciting idea.
Has anyone suggested using the phenomenon of total internal reflection in glass prisms? This is virtually 100 percent efficient.
Wouldn't a big glass prism be massive?
Lots of little ones forming a scaly skin? A cloud of detached beads in front of the spacecraft??
I dunno, just rambling.
Or how about ice crystals?
Could the probe squirt out a little water in front that would make a series of temporary shields of ice crystals? Could you design the atomizing device so that it would preferentially form ice crystals in the vacuum of space with maximum reflectivity? As it breaks down, would it also do decent job of absorbing heat?
(And water is relatively light to carry.)
So we'd be making an artificial comet!
(Really wildly speculating out there)
I notice from reading this months BIS magazine (thanks for the free copy Phil ) that the Australians are now also proposing a solar probe like mission to get to within 3-4 solar radii. No clues as to how they intend to do it though.
http://www.abc.net.au/science/news/stories/2007/2089316.htm
I understand that Johns Hopkins University Applied Physics Lab (JHU/APL) has been studying the solar probe mission. The usual debates about mission capability, payload, and cost continue to swirl.
My source says that the various factions continue to not play nicely (scientists, NASA headquarters, Goddard, contractors) all of which wastes time, money and effort.
There was a Dilbert cartoon once (or perhaps a spoof) where the pointy-haired manager tells Dilbert that the spaceprobe weighs too much so he should delete the science instruments...
R.
Yeah - that was my series of (probably very illegal) 'spacebert' modifications to dilbert cartoons usually talking about Beagle 2
I have just received the author's copies of the March issue of the JBIS, with my article on the history of two 1970s European deep space missions, including the first close perihelion Sun probe study
http://www.jhuapl.edu/newscenter/pressreleases/2008/080501.asp
It seems they plan to use deployable solar arrays (however, the mission home page still states that there will be MMRTGs)
http://science.nasa.gov/headlines/y2008/10jun_solarprobe.htm?list1065474
Seems its becoming a reality.
More detailed technical information here:
http://solarprobe.gsfc.nasa.gov/SolarProbe+ME.pdf
Solar Probe Plus has been given the green light to move into Phase A. Basically, it's a real mission now. Launch is scheduled for 2018 currently, but that's due to budgetary restrictions, not technical ones. According to the APL managers, this mission could go 2-3 years earlier if additional funding was provided.
http://solarprobe.jhuapl.edu/
The launch date on this website is incorrect.
It seems that the ESA Solar Orbiter mission (if selected) would compliment Solar Probe+, and possibly even launch on the same vehicle. ESA's mission won't get as close to the Sun, but having two spacecraft at different radii would allow some synergistic science.
Cool
We can never have too many solar missions
A new article on Solar Probe Plus... 5 science instruments have been selected for the mission
http://science.nasa.gov/science-news/science-at-nasa/2010/02sep_spp/
So will NASA or The Planetary Society have a "Send Your Name to the Sun" campaign before the launch in 2018?
Actually only four instruments mentioned, but radio science isn't mentioned, so that might as well be a 5th.
More on one of the instruments
http://www.spaceref.com/news/viewpr.html?pid=31753&utm_content=api&utm_medium=srs.gs-twitter&utm_source=twitter.com
Wide-field Imager Selected for Solar Probe Plus Mission
Solar Orbiter is selected as ESA's first M-class mission:
http://www.bbc.co.uk/news/science-environment-15146082
selected again, you mean. I don't want to get into politics, but Solar Orbiter has been on and off several times at ESA and was first selected as a medium mission in the early 2000s...
Solar Probe Plus mentioned in this interesting solar wind article:
http://science.nasa.gov/science-news/science-at-nasa/2013/08mar_solarwind/
Also mentioned is WIND, still trucking after almost 19 years...
ESA's Solar Orbiter has recently been delayed from January to July 2017. On the other hand, I have not been able to find the sequence of flybys for the July 2017 launch. Ideas anyone?
Whatever happened to this sun-grazing spacecraft concept ? ....anybody here know ?
it's now known as the Solar Probe Plus, an approved (and funded!) NASA-APL mission for launch in 2018.
http://solarprobe.jhuapl.edu/
Holy 2001-Space-Odyssey-caveman-thrown-bone-turning-into-spacecraft moment!
"A pigment once daubed on cave walls by prehistoric Man will help shield [ESA Solar Orbiter] an unmanned probe that will fly close to the Sun..."
http://phys.org/news/2014-02-stone-age-space-bone-pigment.html#jCp
There is a user of the Orbiter Spaceflight simulator currenly working on simulating both the Solar Probe (+) and the 2005 version, the preliminary models are depicted flying by Venus:
and Jupiter:
New announcement tomorrow on Solar Probe Plus:
http://www.space.com/37023-solar-probe-plus-nasa-announcement-webcast.html
Looking over the details of this mission, and contemplating the current mission finale for Cassini, I'm left wondering about the mission finale for the Parker Solar Probe. Perhaps a final orbit aimed at skimming the solar surface, and transmitting data until the vehicle dies? In the interim, perhaps crank-up the inclination during mission extension so that we get some polar views of the sun like we're getting from Jupiter by the Juno probe?
Yes, I know, it is still way to early to worry about this sort of thing
Oh, and why no ion propulsion? I would have thought this would be the ideal mission for that, in terms of solar power. But it seems to do okay with Venus slingshots.
Perhaps the heat makes ion engines prohibitive?
Regarding a closer approach at the end, I know they were asked at the press conference why they can't dropped the perihelion even closer, and the reply was that once they're inside the orbit of Venus, they can't make any more rendezvous with Venus.
Presumably Mercury is nowhere near a useful trajectory (being more inclined in its orbit, and much less massive.)
Curious will Parker Solar Probe also do Venus Science?
I have found no Information about this google wise.
Here's a link to the http://solarprobe.jhuapl.edu/Spacecraft/index.php#Instruments. Obviously the mission is real heavy on particle & field observations, and I don't know whether the coronal imager (WISPR) is capable of resolving Venus in any useful way. Still, I'm sure they'll record data of some sort during the gravity assists.
Also, since the spacecraft has officially now been named, this topic has been re-titled.
It took me a while to track down the specs of WISPR… many webpages with vague descriptions of it with links to other webpages with other vague descriptions of it. Finally, I got here:
http://www.affects-fp7.eu/helcats-meeting/data/workshop_presentations/20150522_1120_s5_The%20Wide_field%20Imager%20for%20Solar%20PRobe+_WISPR_vbothmer.pdf
If I read it correctly, WISPR would not be capable of providing much useful Venus information. It is a "white light" telescope with one wide bandpass of 475-755 nm (blue to near-IR). That is going to show a very blank Venus with none of the interesting wavelengths (UV or thermal IR). The peak resolution is 4.3 arcmin per pixel which is extremely low resolution by the standards of most of the spacecraft imaging missions we think of. Basically, it's a whole sky camera, like what might be used to take a picture of the Milky Way in the Earth's night sky. For Venus to look interesting to this camera, it would have to be zooming right over Venus's day side at close range, and even then it would be pretty much guaranteed to show a colorless blank image.
I don't think in the best of circumstances WISPR could do any original Venus science.
I wonder if some high-phase angle images with such a camera at fairly close range could show some interesting atmospheric effects. Even the ashen-light if it were to exist. Possibly in the daytime I wonder if there are some subtle colors, either brownish if sulfuric acid absorbs or bluish as Rayleigh scattering contributes along with the clouds.
WISPR wouldn't see color – by "white light" the specs mean a single plane responsive to one wide range of wavelengths, in layman's terms, a black-and-white camera.
The only conceivable advantage over existing datasets would be if it captured Venus' phase angle function from a unique perspective, but Earth-based observations provide basically all angles except the perfectly "full" and perfectly "new" Venus, and we know that Venus Express has covered the "full" phase and multiple orbiters have had the opportunity to image Venus' night side. So I can't see any science coming from this if we're talking about persistent appearance of the planet. Of course, we can never rule out something sporadic light imaging a lightning flash on the night side, although WISPR's quick passes will provide far less chance of that than the long missions of, e.g., Venus Express and Akatsuki.
The launch has been delayed a few times to August 11th; is the first Venus flyby 'locked in' for September 30th because of orbital mechanics? If so, then at six weeks this is probably the fastest launch to Venus encounter (or any planet!) in history!
Mariner 2 was 110 days travel time, Venera 3 we're not certain because of the communications failure, put maybe less. Anyone know for certain?
The time from launch to probe entry for Venera 3 could have been either 105 or 106 days (105 is listed on the Wikipedia article, my date calculation is 106 not taking hours and minutes into account).
Regardless of the launch date, I would expect Parker to arrive at Venus on or near September 30th. Recent Mars probes launched late had pretty close to the same arrival dates. There might be a couple days difference.
More important, they are starting to run out of time. As explained in https://spaceflightnow.com/2018/07/20/launch-of-nasas-parker-solar-probe-rescheduled-for-aug-6/ which was issued for the Aug 6th launch date, they only have until August 19th (or maybe August 23rd at the very latest) to get it off before spending a lot more time and money waiting. And I will guarantee you a different Venus fly by date if that happens.
EDIT I believe the current holder of the record for Earth to Venus is Mariner 10, which made the trip in 95 days. Also, I neglected to notice that this launch differs from the Mars shots I mention due to being a high energy trajectory. So the effect on the arrival date might be more significant, but I don't know by how much.
Latest news is that the Venus flyby will be October 2 based on an August 11 launch. So about 53 days to first encounter from departure.
https://spaceflightnow.com/2018/07/31/solar-probe-moves-into-launch-position-at-cape-canaveral/
"... Driesman told Spaceflight Now he is confident the mission will get off the ground in August.
'The operations are proceeding at what I would call a normal pace,' he said. 'There’s always time built in for not getting things right. At this point, we’re on track for the 11th (of August) launch date.'"
Mariner 10 reached Venus in 94 days. I don't know if that's the record, but I thought it would be worth checking since the whole point of the encounter was for a gravity assist on such a high-delta-v mission.
Cassini Venus to Earth in 1999 was 55 days
Well at least they are launching it at night! For real.
Launch now set for 0753 GMT. Live coverage https://spaceflightnow.com/2018/08/10/delta-4-heavy-parker-solar-probe-mission-status-center/.
Note: For those who have never seen a Delta IV Heavy launch before, the exteriors of the three booster cores tend to...er...catch on fire during initial ascent off the pad. This is caused by entrapped vented hydrogen that is subsequently ignited by the engines, and is both normal and expected. Since this will be a night launch, the effect should be rather spectacular.
T minus 10 min now. So far so good.
GO PARKER!!!!!!!!!
EDIT: No-go for unspecified condition, waiting for new T-0.
EDIT2: New T-0 0828 GMT.
EDIT3: ....aaaaand, scrub.
I believe New Horizons took about 9 hours, from launch, to cross the Moon's orbit, giving it the fastest Earth departure ever.
I suspect Parker may have exceeded that, but can't find the relevant facts -- any ideas?
I was looking for the trajectory views using NASA's Solar System Simulator, seen here for New Horizons :
http://pluto.jhuapl.edu/Mission/Where-is-New-Horizons/
But the same thing does not (yet) seem to be up for Parker.
According to Jonathan McDowell, it was a lot faster (see this tweet: https://twitter.com/planet4589/status/1028699688889933824 .)
And there's this: http://orbitsimulator.com/gravitySimulatorCloud/simulations/1534109533568_parkerPassesMoon.html
A very detailed update on Parker:
https://spaceflightnow.com/2018/08/19/first-mission-milestones-accomplished-on-nasas-newly-launched-parker-solar-probe/
first images from the wide field camera:
https://blogs.nasa.gov/parkersolarprobe/2018/09/19/illuminating-first-light-data-from-parker-solar-probe/
Bit surprised at the quality of these since I thought all the cams were designed for far higher light levels. Pleasantly so, though.
WISPR looks for plasma coming off the Sun, so it's not too surprising it's a decent dark-sky camera.
https://www.youtube.com/watch?v=w3ngdm6GTbc
Maybe it'll get really lucky and find some Vulcan asteroids! Looks like STEREO searches have removed chances of anything larger than ~6km.
Maybe dust impacts could be detected via attitude control.
http://parkersolarprobe.jhuapl.edu/News-Center/Show-Article.php?articleID=105
That's crazy fast. What was the next quickest launch to planetary flyby?
There's discussion of that http://www.unmannedspaceflight.com/index.php?s=&showtopic=1907&view=findpost&p=240555.
Probably one of the previous Venus missions, I think. No other planet gets that close to Earth, and I think we discussed it up thread!
Parker Solar Probe Looks Back at Home
https://www.nasa.gov/feature/goddard/2018/parker-solar-probe-looks-back-at-home
Parker has completed its first solar close approach. Apparently it has been sending back "all is well" tones.
https://spaceflightnow.com/2018/11/06/parker-solar-probe-sets-records-during-first-encounter-with-the-sun/
Second perihelion, same distance as the first, today:
https://blogs.nasa.gov/parkersolarprobe/2019/03/28/parker-solar-probe-approaches-second-solar-encounter/
First scientific results from Parker to be discussed tomorrow at 1:30pm EST, 10:30am PST.
LINK: http://parkersolarprobe.jhuapl.edu/News-Center/Show-Article.php?articleID=131
NASA release http://parkersolarprobe.jhuapl.edu/News-Center/Show-Article.php?articleID=132. Small-scale magnetic field flips in the solar wind & other weirdness.
Earth in a sea of stars amidst the Milky Way
https://i.imgur.com/jiB37M1.gifv
Earth appears in Encounter 2:
https://wispr.nrl.navy.mil/wisprdata
Is that the Moon below and to the left? It seems a bit too bright (and tilted away from the ecliptic).
It's a background star. The Moon was too close to Earth to be resolved.
That's Spica. Parker's WISPR field of view is ~100 degrees, so Earth/Moon aren't resolved. Here's a picture from Eyes on the Solar System about that time. You can see Earth near Spica, and the other fast-moving planet is Mercury zipping past Jupiter.
High definition version of the Parker Solar Probe Earth encounter footage:
https://vimeo.com/377901512
Earth seen from NASA's Parker Solar Probe
Gif: https://i.imgur.com/qjNnhod.gifv
NASA's Parker Solar Probe captured this prospect of Earth against her cosmic backdrop on 1st April 2019. Earth is the bright round spot in the center. The Moon was too close to Earth to be resolved. The background star near Earth is Spica. The curved lines are the result of cosmic rays hitting the camera sensor.
Data Source:
https://wispr.nrl.navy.mil/wisprdata
Parker will make its second flyby of Venus later today, setting it up for its closest pass yet to the sun on January 29. This fourth perihelion will be 20 per cent closer than its first three passes.
Article: http://parkersolarprobe.jhuapl.edu/News-Center/Show-Article.php?articleID=136
Current orbit diagram at the Parker Solar Probe website:
NASA's Parker Solar Probe captured https://vimeo.com/383744252 over the course of ten days in April 2019. Earth is the first bright round spot that shows up and moves to the right of the frame before the Milky Way is seen. The Moon was too close to Earth to be resolved. The background star near Earth is Spica. Mercury is seen in transit across the Milky Way core. Venus is the very bright spot at the end. Jupiter and Saturn are also seen. The stripes are cosmic rays hitting the camera sensor. By the time Parker Solar Probe imaged Venus it was traveling at 95km/s (~213,000mph).
https://wispr.nrl.navy.mil/data/rel/fits/L1/
https://www.jhuapl.edu/FeatureStory/200114
And here's one of the Earth frames (psp_L1_wispr_20190402T170144_V1_2222)
https://apod.nasa.gov/apod/ap200121.html
interesting how its almost looks as if Venus gets born out of some sort of prominence at 0:24 sec in the https://youtu.be/hgzGET6owYk?t=24 and at 1:21 sec in the https://vimeo.com/383744252
https://www.twitter.com/Cmdr_Hadfield/status/1220027345660207104
NASA Parker Solar Probe view of Earth
Earth Image Dataset
https://wispr.nrl.navy.mil/data/rel/fits/CAL1/20180925/
Context
https://www.nasa.gov/feature/goddard/2018/parker-solar-probe-looks-back-at-home
Hey guys, a huge slew of fascinating papers on Parker Solar Probe results - it looks like the near Sun environment is as complex and fascinating as anyone could wish for: https://iopscience.iop.org/issue/0067-0049/246/2
View of The Milky Way from NASA's Parker Solar Probe
Source (Encounter 4):
https://wispr.nrl.navy.mil/wisprdata
New renderings of Earth Encounter 2:
https://vimeo.com/420599154
https://vimeo.com/436115251
Parker probe has been busy spying on comet NEOWISE. I still haven't seen it myself.
https://www.nasa.gov/feature/goddard/2020/nasa-s-parker-solar-probe-spies-newly-discovered-comet-neowise/
Fantastic image of Venus released from this flyby, seeing through to the surface.
https://www.nasa.gov/feature/goddard/2021/parker-solar-probe-offers-a-stunning-view-of-venus
for those using Celestia and want to fallow along, i put up a SPICE enabled add on
-- there might still be a few bugs it is still a work in progress
https://celestia.space/forum/viewtopic.php?f=6&t=20883
A couple of rough-and-ready animations from the flyby:
The two best frames, showing the surface:
I wonder which IR wavelengths would be involved as it could indicate whether one could see either heat emissions, or sunlight scattered through the Venusian clouds. In this case we're looking at the night side, so it must be the heat emissions. The surface of Venus is so hot though that its IR emissions would peak at a relatively short wavelength, that would actually overlap somewhat with the solar spectrum around roughly 3 microns. A look at the atmospheric transmittance spectrum would be of interest.
On Venus, the temperature varies very linearly with altitude. The atmosphere itself radiates in IR, but the surface is still much, much denser than even Venus's dense atmosphere, so what we primarily see is a measure of the altitude. It's been established that the thermal IR signature for the surface corresponds to about 1 micron. 2+ microns moves the observation vertically upward into the atmosphere, and examines structure in clouds. (I was pleased, in early 2020, to join the ranks of amateurs who have imaged the surface of Venus looking through the nightside clouds at 1 micron.)
What makes this more complicated is that there are windows in the atmosphere (of course, primarily CO2) that pass IR better than others. The planned emissivity observations that would take place in any of the proposed remote sensing missions to Venus would take advantage of these.
I have to say that I'm quite surprised that the PSP imager achieved this level of signal pertaining to the surface of Venus. The detail is certainly there in certain narrow bands, but with a wide-band filter I would expect the noise to overwhelm the signal. I'm perplexed that PSP would achieve such a clear signal by accident, because it's quite difficult to do when trying to do so. One advantage for PSP vs. an earthbound observer is that from certain vantage points close to Venus and over its nightside, one can avoid much of the glare from the crescent of the dayside. Even a very slim crescent at the intense illumination of Venus's clouds can glare and ruin the image over much of the nightside.
What's going on with all the streaks? These pictures make space seem very... not-empty.
This is the http://parkersolarprobe.jhuapl.edu/News-Center/Show-Article.php?articleID=160 explanation, but I still have questions:
Protons from the Sun are a type of cosmic ray and PSP is uniquely close to the Sun.
The trails can curve as they lose energy inside a solid medium.
Of course, one variable that drives up the number of artifacts is the exposure duration, and seeing the night side of Venus involves a relatively high exposure duration, but that depends on a lot of variables.
Deep Sky Object imagery is pretty prone to pick up on both cosmic ray hits and (from Earth, more likely) satellite / space junk / asteroid trails, and in images where you don't see those, there's a good chance that someone made an effort to remove them. I tend to shoot multi exposure images and when one out of many frames has such a flaw, I just don't use that frame for that part of the composite. for example.
Hi. Longtime lurker here....working in the field of cosmic rays
It seems to me that the image shows a combination of stellar objects on the background, producing the left to right streaks due to the long exposure, with stratight traces from cosmic rays on the ccd, plus particles moving in the near field during said exposure time. Why do they move like that? local electromagnetic fields from the spacecraft? radiation pressure?...no idea!. But electrostatic forces alone would produce more straight lines wouldnt they?
The PSP is constantly being hit by hyper-velocity dust particles. It's easy to forget that PSP is not only coming into close proximity to the Sun, but also traveling through inter-planetary dust at unusually high velocities, making those impacts with microscopic dust particles far more impactful. This may speak to some of the earlier questions about image artifacts as a phenomenon which is, basically, so far unique to PSP alone among all interplanetary spacecraft.
https://phys.org/news/2021-11-tiny-grains-severe-hypervelocity-impacts.html
From the report:
I am most taken aback by the mention of "paint chips." Keep your paint away from my spacecraft...
Good catch, Ralph. I think the main difference with STEREO is that the impacts in that case led to fragmentation into smaller solid secondaries, while at the hypervelocity of PSP, the impactors are being turned into plasma.
Parker Solar Probe entered the solar corona for the first time during its eighth orbit back in April this year (2021). It has since flown by Venus again and just completed its tenth pass even closer.
This result released today. LINK: https://www.nasa.gov/feature/goddard/2021/nasa-enters-the-solar-atmosphere-for-the-first-time-bringing-new-discoveries
YouTube video: https://www.youtube.com/watch?v=LkaLfbuB_6E
Some rather unexpected results from the latest close flybys of the sun by Parker. Electromagnetic waves called "whistlers" help control heat flow in regions of the solar wind beyond 35 solar radii (about 0.16 AU). Inside of 28 solar radii however, the whistlers almost disappear, and instead there were electrostatic rather than electromagnetic waves that took over.
This is reported in a free access paper at the website for Astrophysical Journal Letters.
"The surprising observation that whistler-mode waves are almost never observed inside ∼28 Rs (∼0.13 au) is crucial for understanding the evolution of the solar wind close to the Sun. "
LINK: https://iopscience.iop.org/article/10.3847/2041-8213/ac4015
Not sure if this should go under Parker or Venus... but Parker's WISPR instrument got something unexpected when they took some nighttime shots, expecting to see cloud tops... https://www.nasa.gov/feature/goddard/2022/sun/parker-solar-probe-captures-its-first-images-of-venus-surface-in-visible-light-confirmed. Never expected to see this - fantastic
Sad news to report
https://www.nasa.gov/press-release/nasa-mourns-passing-of-visionary-heliophysicist-eugene-parker
Scientists at Johns Hopkins Applied Physics Laboratory have released a video of the Parker Solar Probe passing through an especially powerful coronal mass ejection that took place last year. The video is here https://www.youtube.com/watch?v=FF_e5eYgJ3Yhttps://www.youtube.com/watchv=FF_e5eYgJ3Y
And here is a link to the Spaceweather page of 9/6/2022 that contains observations of the CME of 9/5/2022 as observed by NASA's Stereo A and Europe's Solar Orbiter probes. https://spaceweather.com/archive.php?view=1&day=06&month=09&year=2022
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