Comments and questions about the
APOD on the main view screen.
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APOD Robot
- Otto Posterman
- Posts: 5599
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by APOD Robot » Sun Jul 12, 2015 4:12 am
New Horizons Launch to Pluto
Explanation: Destination: Pluto. The
New Horizons spacecraft roared off its launch pad at
Cape Canaveral in
Florida,
USA in 2006 toward adventures in the distant
Solar System. The craft is the
fastest spaceships ever
launched by humans, having passed the Moon only nine hours after launch, and
Jupiter only a year later. After spending almost a decade crossing the Solar System,
New Horizons will fly past
Pluto on Tuesday.
Pluto, officially a
planet when New Horizons launched, has never been visited by a spacecraft or photographed up close. After
Pluto, the robot spaceship will visit one or more
Kuiper Belt Objects orbiting the Sun even further out than Pluto.
Pictured, the New Horizons craft launches into
space atop a powerful
Atlas V rocket.
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alter-ego
- Serendipitous Sleuthhound
- Posts: 1123
- Joined: Mon Apr 21, 2008 4:51 am
- Location: Redmond, WA
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by alter-ego » Sun Jul 12, 2015 4:31 am
APOD Robot wrote:
After
Pluto, the robot spaceship will visit one or more
Kuiper Belt Objects orbiting the Sun even further out than Pluto.
HubbleSite wrote:This was a needle-in-a-haystack search for the New Horizons team because the elusive KBOs are extremely small, faint, and difficult to pick out against myriad background stars in the constellation Sagittarius, which is in the present direction of Pluto. The three KBOs identified are each a whopping 1 billion miles beyond Pluto. Two of the KBOs are estimated to be as large as 34 miles (55 kilometers) across, and the third is perhaps as small as 15 miles (25 kilometers).
Wow, quite an accomplishment.
Edit: Assuming no further acceleration (probably
not is the case), NH should encounter a KBO within about 3
to 4 years from now.
Last edited by alter-ego on Sun Jul 12, 2015 6:23 am, edited 1 time in total.
A pessimist is nothing more than an experienced optimist
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Jim Leff
- Science Officer
- Posts: 193
- Joined: Thu Dec 09, 2010 2:00 pm
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by Jim Leff » Sun Jul 12, 2015 5:19 am
How did they achieve the launch speed? Was the rocket stocked with extra fuel, or was it a light load, or....?
It wasn't a particularly novel rocket, I don't believe....
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alter-ego
- Serendipitous Sleuthhound
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Post
by alter-ego » Sun Jul 12, 2015 6:17 am
Jim Leff wrote:How did they achieve the launch speed? Was the rocket stocked with extra fuel, or was it a light load, or....?
It wasn't a particularly novel rocket, I don't believe....
Scientific American wrote: We can start off easy though. Launch velocity is something very definite, tuned to the finest level possible in order to insert a mission into its optimal trajectory. The record holder is also easy to find, it's the New Horizons mission to Pluto and the Kuiper belt.
Launched by NASA in 2006,
it shot directly to a solar system escape velocity. This consisted of an Earth-relative launch of 16.26 kilometers a second (that's about 36,000 miles per hour), plus a velocity component from Earth's orbital motion (which is 30 km/s tangential to the orbital path). Altogether this set New Horizons barreling off into the solar system with an impressive heliocentric speed of almost 45 km/s or 100,000 miles per hour.
The Sun's pull is relentless though, so sometimes you need a helping hand. In 2007 New Horizons had slowed to about 19 km/s and made a flyby of Jupiter to snag a gravity assist (where the spacecraft 'stole' a tiny bit of Jupiter's momentum) in order to regain about 4 km/s - before settling in for the long coast outwards. In the first figure shown here you can see how this is going to play out - heliocentric velocity is going to slowly drop during the journey through the Sun's ever weakening gravity field. However, when it encounters Pluto, the spacecraft will still whizz by at about 14 km/s relative velocity.
Of course the Atlas V (see link) is a heavy-lift launch platform - it was, and possibly still is, in 2nd place to the Saturn V.
You might find the SA article interesting. It's titled:
The Fastest Spacecraft Ever?
A pessimist is nothing more than an experienced optimist
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Joules
- Ensign
- Posts: 45
- Joined: Wed Feb 12, 2014 11:49 am
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by Joules » Sun Jul 12, 2015 12:28 pm
That's a very nice example of a shot best taken with a remote camera.
I'd not like to be standing there in the open when the rocket took off.
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Jim Leff
- Science Officer
- Posts: 193
- Joined: Thu Dec 09, 2010 2:00 pm
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by Jim Leff » Sun Jul 12, 2015 12:29 pm
Thanks, but that just restates that it went fast. I'm asking how that speed was achieved....on only the second fastest rocket (even if it had used the fastest rocket, that still doesn't explain how this particular launch was faster than all previous ones).
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neufer
- Vacationer at Tralfamadore
- Posts: 18805
- Joined: Mon Jan 21, 2008 1:57 pm
- Location: Alexandria, Virginia
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by neufer » Sun Jul 12, 2015 1:03 pm
Jim Leff wrote:
Thanks, but that just restates that it went fast. I'm asking how that speed was achieved....on only the second fastest rocket (even if it had used the fastest rocket, that still doesn't explain how this particular launch was faster than all previous ones).
Voyager I weighted 50% more than NH and was launched from a less powerful/efficient rocket.
Art Neuendorffer
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Dad is watching
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by Dad is watching » Sun Jul 12, 2015 3:38 pm
alter-ego wrote:
Launched by NASA in 2006, it shot directly to a solar system escape velocity. This consisted of an Earth-relative launch of 16.26 kilometers a second (that's about 36,000 miles per hour), plus a velocity component from Earth's orbital motion (which is 30 km/s tangential to the orbital path). Altogether this set New Horizons barreling off into the solar system with an impressive heliocentric speed of almost 45 km/s or 100,000 miles per hour.
Ok, so the NH probe is going at solar system escape velocity. But doesn't that also mean the the final stage/boost stage of the launch vehicle is also going equally fast? We figured that some separation between probe and launch vehicle was made using some sort of reaction/maneuvering thrusters so that the probe is free and clear to navigate. But what happened to the launch vehicle going that fast? Is it just headed out into deep space on its own like a bullet fired blindly from a gun? We assume that solar system escape velocity means that it will not return our way again, and that it will end up in some kind of independent orbit around the galaxy itself??? Is that right?
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BPCooper
- Ensign
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by BPCooper » Sun Jul 12, 2015 4:25 pm
An added solid fuel third stage (a Star 48B) gave New Horizons the speed it needed. The combination of NH's light weight and the power given made NH the fastest spacecraft to date to depart from Earth specifically. Yes, this stage is also on an escape trajectory, but its trajectory has taken it well away from NH and Pluto at this point.
In terms of a "novel rocket" and comparisons to others, the Atlas 5 in this case flew in the most powerful configuration it could with five added solid boosters and a third stage added. In terms of comparison to other vehicles, it is big compared to others but it is not close to that of the Saturn. But what matters more is spacecraft size, which was very small in this case.
The potential Kuiper Belt objects NH will encounter have already been narrowed down to two, and the encounter would be in either January 2019 or June 2019. A selection is expected next month (August).
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Boomer12k
- :---[===] *
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by Boomer12k » Sun Jul 12, 2015 7:41 pm
Man, that's a lot of smoke....
Great Pic...
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saturno2
- Commander
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by saturno2 » Mon Jul 13, 2015 3:32 am
Very interesting
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DavidLeodis
- Perceptatron
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by DavidLeodis » Mon Jul 13, 2015 12:48 pm
In the information brought up through the 'Pictured' link it states "New Horizons became the first spacecraft in history to visit Pluto on July 14, 2015, giving us the first view of the only one of the "classic nine" planets not yet explored". I hope that is not a case of counting chickens before they hatch as it's only July 13 when I posted this!
Assuming all does go well it will be a great achievement
. OK that's a puppy but it's the nearest smilie to represent Pluto (the cartoon dog in case anyone wonders what I'm going on about
)
.