Fastest Spacecraft Ever?!?, Which one is it? Options

[Toma B]

There was statement that recently launched New Horizons is the fastest spacecraft to leave Earth. The velocity was 16.2 km/s relative to the Earth according to "Jonathan's Space Report".

After the Star 48B burn, the payload had reached escape velocity not only with respect to the Earth but also relative to the Sun (The velocity was 16.2 km/s relative to the Earth and I estimate an asymptotic velocity of 12.3 km/s, corresponding to 42.6 km/s relative to the Sun...

So:
New Horizons is fastest to leave Earth at 16.2 km/s (relative to Earth).
Voyager-1 is fastest to leave Solar System at 17.374 km/s (relative to Sun).

Now that is OK. but what is this?
Today's "Astronomy Picture of the Day" features launch of New Horizons and in text bellow image is one particularly interesting link to "Guinness world of records"...
Guinness world of records;
There "Mr. Guinness" claims that the fastest spacecrafts ever, were two Solar probes "Helios 1&2"...According to him those spacecrafts had speed of 252,800 km/h which is staggering 70.2 km/s...BUT RELATIVE TO WHAT?????
Can somebody explain this?

[ugordan]

BUT RELATIVE TO WHAT?????

It's all relative...

Personally, I wouldn't get that much excited about the "fastest ever" claims.

[Alan Stern]

There was statement that recently launched New Horizons is the fastest spacecraft to leave Earth. The velocity was 16.2 km/s relative to the Earth according to "Jonathan's Space Report".

So:
New Horizons is fastest to leave Earth at 16.2 km/s (relative to Earth).
Voyager-1 is fastest to leave Solar System at 17.374 km/s (relative to Sun).

Now that is OK. but what is this?
Today's "Astronomy Picture of the Day" features launch of New Horizons and in text bellow image is one particularly interesting link to "Guinness world of records"...
Guinness world of records;
There "Mr. Guinness" claims that the fastest spacecrafts ever, were two Solar probes "Helios 1&2"...According to him those spacecrafts had speed of 252,800 km/h which is staggering 70.2 km/s...BUT RELATIVE TO WHAT?????      
Can somebody explain this?

Relative to the Sun, I suspect. They were in very tight solar orbits.

[edstrick]

The fastest spacecraft ever, relative to what it's primarily interacting, may well have been the Galileo entry probe. The 70 km/sec figure would have been heliocentric orbital speed at perihelion, I presume...well inside Mercury's perehelion.

A more significant "figure of merit" would have been the toltal "Delta-V" of a spacecraft due to powered flight.

[odave]

Here's a pointless activity for the space sim jocks - though after hearing about dB Drag Racing I know that people do invest a lot of time in apparently pointless activities.

If you wanted to build and launch a spacecraft with the sole purpose of exiting the solar system and beating Voyager 1's sun-relative speed, what combination of today's launch vehicles and gravity assists would you use, given a spacecraft mass equivalent to V1?

I'd fiddle about with it myself, but I think the learning curve would outstrip the amount of free time I have.

[ljk4-1]

Here's a pointless activity for the space sim jocks - though after hearing about dB Drag Racing I know that people do invest a lot of time in apparently pointless activities.  

If you wanted to build and launch a spacecraft with the sole purpose of exiting the solar system and beating Voyager 1's sun-relative speed, what combination of today's launch vehicles and gravity assists would you use, given a spacecraft mass equivalent to V1?

I'd fiddle about with it myself, but I think the learning curve would outstrip the amount of free time I have.

A solar sail vessel could pass Pluto's orbit in just five years and outdistance Voyager 1 shortly after that. It could reach the nearest star in "only" a thousand
years or so. And this is just with solar light. With a powerful enough laser... fuggedaboutit.

http://www.planetary.org/solarsail/faqs.html

[tasp]

I can't find the thread here right now, but the manhole cover blasted with a nuke might rate a mention in this thread.

[ljk4-1]

I can't find the thread here right now, but the manhole cover blasted with a nuke might rate a mention in this thread.

Here ya go:

http://www.unmannedspaceflight.com/index.p...1955&hl=manhole

How much of that manhole cover could have survived into space anyway?

[ugordan]

How much of that manhole cover could have survived into space anyway?

The shortest answer is : probably nothing. It was moving so fast and in the densest part of the atmosphere that even if it somehow survived being vaporized by friction, it would likely have fallen back down some distance away, probably not reaching very high up in the first place.
Keep in mind just how powerful friction is even up there, tens of kilometers up in the atmosphere where all those meteors get disintegrated, let alone here at the surface...

[RNeuhaus]

Ulysses still holds as the fastest escape velocity from Earth: 15.17 km/sec versus to NH 12.3 km/sec relative to Earth.

Fastest Earth Departure Speed
The fastest escape velocity from Earth was 54,614 km/h (34,134 mph), achieved by the ESA Ulysses spacecraft after deployment from the Space Shuttle Discovery on October 7, 1990. It was en route to an orbit around the poles of the Sun via a fly-by of Jupiter.


Record Guiness

Ulysses was launched by the Space Shuttle Discovery on 6 October 1990 at 11:47:15 UTC. The Payload Assist Module (PAM-S) which propelled Ulysses away from the Earth toward Jupiter.

Rodolfo

[Guest_PhilCo126_*]

I guess it's pretty difficult to come up with the current speed of the Voyagers and Pioneers ( via Radio doppler but their signal is very faint ) ... but shouldn't we take the distance Earth-Moon as basic measurement?
( Apollo CSM did it in 90 Hours, Pioneer 10 in 11 hours, New Horizons in 9 hours ... don't know about the Helios spacecraft )

[remcook]

"I guess it's pretty difficult to come up with the current speed of the Voyagers"

http://voyager.jpl.nasa.gov/mission/weekly-reports/index.htm

[Alan Stern]

Ulysses still holds as the fastest escape velocity from Earth: 15.17 km/sec versus  to NH 12.3 km/sec relative to Earth.

Fastest Earth Departure Speed
The fastest escape velocity from Earth was 54,614 km/h (34,134 mph), achieved by the ESA Ulysses spacecraft after deployment from the Space Shuttle Discovery on October 7, 1990. It was en route to an orbit around the poles of the Sun via a fly-by of Jupiter.


Record Guiness

Ulysses was launched by the Space Shuttle Discovery on 6 October 1990 at 11:47:15 UTC. The Payload Assist Module (PAM-S) which propelled Ulysses away from the Earth toward Jupiter.

Rodolfo

NH left Earth at 16.2 km/sec.

[djellison]

Who's up for Top Trumps. I think Alan just won.

Doug

[BPCooper]

NH is fastest to be propelled away from Earth. The other probes got it from other gravity weels (Helios from the Sun). NH will not exceed Voyager's speed, which it obtained during its flybys.