New Horizons I (and II!) Mission Update Thread

[ve7rkt]

> Now for homework workout just how large it would have to be to have a Pluto orbit insertion stage. <br /><br />By my math, you need a rocket that'll blow off ~13.6km/s to park in Pluto orbit. No chemical rocket is going to do that, at least not in a single stage (best storable rocket I can find is the Star 63F, and even if you upscale it to the size of the Moon and park New Horizons on the front, it'd still whiz past Pluto at nearly 6km/s). If you want to stop at Pluto, you have to either invent a storable chemical rocket with an Isp somewhere above 530sec (it's magic, it's powered by love), or fly there slower.

 

[ve7rkt]

A xenon-ion-electric orbit insertion stage could be done. I worked one out to a total launch mass (probe + engine + fuel + 3.5% fuel mass in tankage + 1% fuel mass in structure + ELEVEN Cassini-like RTGs to power it) of 2521kg. That's assuming that New Horizons itself can handle the work of pointing a spacecraft five and a half times its own mass.<br /><br /><b>Down sides:</b> You need a launcher with six times the capacity of the Atlas V that threw New Horizons. Also, the orbit insertion burn would last for <i>over six years</i>, which would delay its arrival to Pluto by quite a bit.

 

[brandbll]

Would it be conceivably easier for it to insert into Neptune's orbit with the speed it is going? Not talking about trajectory really but just with the speed it's going? <div class="Discussion_UserSignature"> <p><font size="3">You wanna talk some jive? I'll talk some jive. I'll talk some jive like you've never heard!</font></p> </div>

 

[ve7rkt]

I don't know. On one hand, Neptune's higher gravity should mean a faster speed in orbit. I'm using moons for references; an object in the same orbit as Charon orbits Pluto at around 230m/s, an object in the same orbit as Triton orbits Neptune at 4.39km/s. 4.16km/s less work makes a big enough difference to shrink the xenon tank on an ion-electric insertion stage, but not enough to go with chemical propellants.<br /><br />On the other hand, on the approach, Neptune will pull harder, so the probe will be going faster as it makes its approach. I don't have the math to figure that out.

 

[brellis]

Thank you for the math lesson on xenon ion-electric engines. So many questions from an eager bystander:<br /><br />Could solar panels transfer enough energy to power an ion engine on a craft beyond the orbit of Mars? <br />How heavy is one of these engines compared to a chemical propellant engine? <br />Could one be used to keep, for example, Hubble or ISS in orbit for another decade? <br />Could xenon ion-electric be incorporated into a "Slower, Cheaper, Better" program of large-scale platform/colony construction? <br />When you consider how many years it takes to get these programs funded, the time it takes for one of these gadgets to get going seems insignificant, at least for unmanned missions. <div class="Discussion_UserSignature"> <p><font size="2" color="#ff0000"><em><strong>I'm a recovering optimist - things could be better.</strong></em></font> </p> </div>

 

[3488]

An Ion engine would work on both the Hubble Space Telescope & the ISS, but because the ISS is so massive, I think Ion engines would either have to be huge, with enormouse solar panels or large RTGs to power them or would need to be supplemented with normal hydrazine trusters.<br /><br />A Pluto orbiter will almost certainly follow on if New Horizons show that Pluto, Charon, Nix & Hydra were worthy of further investigation. A lander on Pluto would also be worth considering.<br /><br />Pluto may still get relegated from planetary status if other objects of the size of 2003 UB313 or larger are found, regardless of how many moons Pluto has. <br /><br />2003 UB313 has been found to have at least one moon, at least 250 kilometres / 155 miles across, larger than either Nix or Hydra (although considerably smaller than Charon). 2003 UB313, like Pluto will probably have more than one moon. <br /><br />2003 EL61 has been found to have two moons as well as 2003 EL61 being a weird cigar shape, its long axis is larger than either Pluto or 2003 UB313.<br /><br />New Horizons is really the last of the Recon spacecraft, the first to take a peek at the Pluto system. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[jmilsom]

The latest PIs Perspective has been posted on the mission site (first update for 6 weeks):<br /><br />http://pluto.jhuapl.edu/overview/piPerspectives/piPerspective_current.php<br /><br />It answers a question posted by brandbll last month and concerning the Jupiter flyby:<br /><br /><font color="yellow">The New Horizons Jupiter Encounter Science Team (yes, JEST), led by Dr. Jeff Moore of NASA Ames and Dr. John Spencer of Southwest Research Institute, has turned in its Jupiter observation plan. This plan was formally communicated to the mission operations team in an all-day review on June 26. The Jupiter observing plan, which stretches from January to June 2007, has more than 500 separate observations in it. Observations resulting from this plan should yield major advances on everything in the Jupiter system from the Galilean satellites to the red spots to Jupiter's magnetosphere and aurora, and the Jovian rings.</font><br /><br />So there will be a period of about 6 months during which useful science will be possible at Jupiter.<br /><br />I see also that the JF56 flyby was a great success and the team has proposed to the IAU that it be named "Johns Hopkins Applied Physics Lab!" <br /><br />Mission elapsed time: <br /><br /><font color="orange">Days 178 Hours 07 Minutes 05</font><br /><br />Jupiter closest approach <br /><br /><font color="orange">Days 226 Hours 03 Minutes 35</font><br /><br />Pluto closest approach!!!! <br /><br /><font color="orange">Days 3284 Hours 09 Minutes 53</font>/safety_wrapper> <div class="Discussion_UserSignature"> </div>

 

[gunsandrockets]

"An Ion engine would work on both the Hubble Space Telescope & the ISS, but because the ISS is so massive, I think Ion engines would either have to be huge, with enormouse solar panels or large RTGs to power them or would need to be supplemented with normal hydrazine trusters."<br /><br />I've heard the ISS uses about 7 tonnes of propellant per year for reboosting. The equals about 700 kg of propellant per year for an ion engine.<br /><br />The NSTAR ion engine as used on Deep Space One has a mass of 8 kg and consumes about 1 kg of propellant every 8 days of thrusting. So about 15 NSTAR engines should do the trick requiring a total of 35 kilowatts of power, well within the power budget of the Space Station.

 

[3488]

I hope that we will get some good observations of volcanic Io. I hope (at some point) to convince NASA to carry out a dedicated Io mission (orbiter & a lander).<br /><br />It will be interesting to see what the current state of volcanic activity is there at the time.<br /><br />It is good to see that New Horizons is continuing to operate well. <br /><br />Already speculation about what New Horizons will see at Pluto & Charon is rampant (I remember similar speculation about the Neptune moon Triton, prior to the arrival of Voyager 2). <br /><br />I wonder if Red Spot Junior will still be there when New Horizons arrive? <br /><br />I understand that the Great Red Spot is going to be investigated in detail, should be very interesting!! <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[kane007]

From SpaceDaily.com<br /><br />2006/07/17<br /><br />On Friday, July 14, we stood precisely nine years from our closest approach date with the ninth planet and her moons. Next week, on July 19, we will celebrate the six-month anniversary of our launch. New Horizons has a long way to go, but we're on our way!<br /><br />It's been six weeks since my last column here, and a lot has taken place. Here's a short list of highlights:<br /><br />- New Horizons successfully conducted an asteroid flyby test of its moving target image motion compensation system (more on that below).<br /><br />- The names we nominated for Pluto's two recently discovered small moons, Nix (the inner one) and Hydra (the outer one), were approved by the International Astronomical Union (IAU).<br /><br />- Continued successful testing of the SWAP and PEPSSI plasma/high energy particle detector suite aboard New Horizons.<br /><br />- Successful beam mapping tests of the REX-High Gain Antenna pattern.<br /><br />- Uploading of an updated (yes, "new and improved") release of the onboard fault detection and correction "autonomy" software that watches over New Horizons.<br /><br />- A spin-up maneuver that took New Horizons out of three-axis attitude control and placed it back in its 5 RPM axial spin to save fuel and place us in a more robust mode for the upcoming flight software loads of August and September.<br /><br />Traveling more than 70,000 kilometers (43,500 miles) per hour, 24x7, New Horizons is now closer to Jupiter than it is to the Sun; check this out at http://www.pluto.jhuapl.edu/mission/whereis_nh.php. By the end of July, our ship will be passing the distance of Ceres, the largest member of the asteroid belt and a relic of our solar system's planetary formation days.<br /><br />Ceres and Pluto have something important i

 

[gunsandrockets]

Ceres and Pluto as 'dwarf planets'. I like that! That makes for a simple classification scheme by division into terrestrial, gas-giant and dwarf planets. It makes sense to me to qualify Ceres and Pluto as planets instead of an asteroid or Kuiper Belt object since they both are massive enough to form a spherical shape.

 

[jmilsom]

Not much news this month on NH1. With the IAU decision on planet classification (which I think is great and I am sure has made the NH1 team happy), threads have popped up all over uplink to discuss this. Many have questioned the classification applying to Charon.<br /><br />There is a great page on the NH1 mission site, on the Pluto-Charon system, which has an animation showing the two planets revolving around their gravitational centre of mass. Have a look!<br /><br />http://pluto.jhuapl.edu/science/everything_pluto/10_binary_planet.html<br /><br /><br />Mission elapsed time: <br /><br /><font color="orange">Days 210 Hours 04 Minutes 58</font><br /><br />Jupiter closest approach <br /><br /><font color="orange">Days 194 Hours 05 Minutes 42</font><br /><br />Pluto closest approach!!!! <br /><br /><font color="orange">Days 3252 Hours 12 Minutes 00</font><br /><br /> <div class="Discussion_UserSignature"> </div>

 

[3488]

That is pretty cool (I did look at it yesterday, but have looked at it again just now through your link).<br /><br />Clearly Pluto & Charon ARE a double planet, more so than the Earth & our moon (where the centre of gravity is just above the outer core, lower mantle boundary). <br /><br />When New Horizons arrive, it will be fascinating to see what similarites & differences there are between Pluto & Charon (whether or not Charon, Nix & Hydra are the results of a collision).<br /><br />I understand that our own Moon is being considered, along with the asteroids: 2 Pallas, 4 Vesta, 5 Hygeia (3 Juno is too small) & the KBOs: Quaoar, 2005 FY, Orcus, Varuna, Ixion & Sedna. <br /><br />If so the planetary tally of the Solar system will rise to 22!! <br /><br />It should be soon now that the details of the Jupiter system encounter next February will be made known. <br /><br />The Great Red Spot is to be studied in great detail, Red Spot Junior will also be observed & my requests for extended Io observations have been accepted (I was able to make a strong enough case).<br /><br />New Horizons does appear to cross the orbit of Neptune at the trailling Lagrangian point from Neptune. Do we know if New Horizons could encounter a Neptunian lagrangian asteroid?<br /><br />I have seen a graph showing the trajectory of New Horizons through the Pluto system showng Pluto & Charon. Is there a more updated one showing the positions of Nix & Hydra? What will the size of the smallest details seen on both will be?<br /><br />Andrew Brown. <br /> <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[jmilsom]

<font color="yellow">If so, the planetary tally of the Solar system will rise to 22!!</font><br /><br />If the oligarchic theory for the formation of our solar system proves to be more accurate, that number may one day double again!<br /><br />Re: your last question. I have not seen an updated mission trajectory yet that includes the positions of Nix and Hydra. I'll see what I can dig up.<br /><br />Mission elapsed time: <br /><br /><font color="orange">Days 212 Hours 08 Minutes 14</font><br /><br />Jupiter closest approach <br /><br /><font color="orange">Days 192 Hours 02 Minutes 38</font><br /><br />Pluto closest approach!!!! <br /><br /><font color="orange">Days 3250 Hours 08 Minutes 56</font>/safety_wrapper> <div class="Discussion_UserSignature"> </div>

 

[teije]

I have some questions about the mission.<br /><br />Does anyone know how much dV New Horizons will get off the Jupiter flyby?<br /><br />New Horizons will be flying through Neptune's trailing Langrange point. Are there any trojans known that NH could investigate?<br /><br />What is the plan undertaken to find KBO's beyond the Pluto - Charon encounter that could be possible NH secondary targets?<br /><br />Thanks in adv!<br />Teije

 

[3488]

Apparently there are no known KBO targets at the present time. <br /><br />A decision will be made during the next 9 years. KBO searches are being undertaken all the while & I am sure there will be a grab bag of possible selections come post Pluto system encounter.<br /><br />I have already asked about the potential Neptune trailing trojan, but have yet to receive a response. I am sure that nearer the time, there will be dedicated search programmes to see if such an encounter happens. I hope so very much & see how a Neptune trojan compares with the captured Saturn moon Phoebe. <br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[teije]

Thanks Andrew.<br />Even if the answer summarizes as: 'we don't know yet' it's still good to know they're working on it. And like you said, they have quite a bit of time. <br />Jupiter encouter first.<br /><br />Teije <br /><br />Edit as an after thought:<br />I feel rather sorry today for Alan Stern. They have demoted his planet to 'dwarf planet' status. He sounds furious on today's SDC article. Even though I'm in the 8 planets camp I can imagine him not liking this at all. Although it does nothing for how interesting an object Pluto is. <br />I think the latest word about what a 'planet' is has not yet been said. And Pluto just might get promoted again before the NH flyby.<br /><br />Teije

 

[spacester]

Otto Krause wrote a paper in 2003 while at U of Colorado that is illuminating. Thanks, Otto, wherever you are! <img src="/images/icons/smile.gif" /><br /><br /><i>The solution currently in plan is to do a survey of the possible objects around the 2009 timeframe. This is due to the fact that many of the potential KBO targets are too dim to see since they're in the center of the Milky Way galaxy with respect to Earth. This is hampered by the fact that objects as dim as 27 orders of magnitude need to be observed to be within reach of New Horizons. An advantage to observing KBOs soon is that accurate orbits could be modeled, but waiting for a few years implies that a smaller portion of the sky will need to be searched. The bottom line is that at least 2-3 years of observations are required to get a good data set for an orbit, so the 2009 timeframe is still reasonable, as the Pluto encounter doesn't occur until 2015 and that leaves 6 years for the search. Objects both in plane with the trajectory and out of plane will be examined, in effect showing a cone of possible trajectories. See Figure 3. The governing equation over the volume that's available to New Horizons is the following:</i> <div class="Discussion_UserSignature"> </div>

 

[teije]

That indeed was illuminating. Thanks Spacester (and Otto.)<br />Unfortunately we don't have 8 km/s of delta-v left over somewhere, or we could have visited Quaoar. <img src="/images/icons/smile.gif" />

 

[alokmohan]

Will new horizon contnue after demotion of pluto?

 

[comga]

You cannot be serious. Of course New Horizons continues on to Pluto and beyond it. Pluto remains exactly as it was and has been for a billion years. Regardless of what name we give it, it remains fascinating and enigmatic, and New Horizons will go there no matter what we do, so why should we take any fewer images or less spectra than we possibly can?<br /><br />Although the IAU has made a mess of this, which was probably inevitable, Alan Stern did get part of what he wanted. They are calling Pluto a dwarf planet, which is what he calls it. The IAU saying that a dwarf planet is not a planet is just sloppy.

 

[alokmohan]

But tell me if new horizon is a planetary mission?I think now the answer is yes and no.

 

[brellis]

lol, did it get reduced to a 'dwarf' planetary mission? <div class="Discussion_UserSignature"> <p><font size="2" color="#ff0000"><em><strong>I'm a recovering optimist - things could be better.</strong></em></font> </p> </div>

 

[alokmohan]

Is it not logically imperative?

 

[bdewoody]

This is getting rediculous. The mission objectives will remain the same. You can't recall the darned thing and I'll bet there's no desire to anyway. How a group of astronomers decide to classify an object has no impact on it's physical properties which is what New Horizons was designed to determine. Who knows what the status quo will be in 15 years when the probe gets there? <div class="Discussion_UserSignature"> <em><font size="2">Bob DeWoody</font></em> </div>