## Planet Hunters Report Record-Breaking Discovery, Search for other habitable planets

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Stargate (S.A.)
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Message 1927025 - Posted: 29 Mar 2018, 5:12:17 UTC - in response to Message 1927022.

My calculations show that light will travel 23,498,356,608,000 miles in 4 years based on a speed of 186,282 mps. So at 50,0000 mph it would take an object 53,649.216 years to travel that distance.

Bugger.. Would have a nice head of grey hair in that time :(
ID: 1927025 ·
William Rothamel

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Message 1927082 - Posted: 29 Mar 2018, 12:43:44 UTC - in response to Message 1927022.

Bob,

I think that you are off by a big factor. I will check your work. I gave this problem to my Physics students before I got fired at Belmont University for telling a student that he made a good deduction in class and should be getting better grades ! I seem to recall 25 trillion or so.
ID: 1927082 ·
William Rothamel

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Message 1927083 - Posted: 29 Mar 2018, 12:57:46 UTC - in response to Message 1927082.

Bob, I see that your calculations are indeed correct. 24 trillion miles to Alpha /Proxima Centauri. Give yourself a raise in pay.

This points out the stark truth that to travel to a new Earth will require a power source/engine that can deliver one G or so acceleration for a sustained period of perhaps several years. So it's possible to reach Alpha Centauri in less time but I posit not with less energy than calculated by a sustained acceleration of a few G over a 25 trillion mile distance for whatever mass you think that the space ship might have..
ID: 1927083 ·
moomin

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Message 1927091 - Posted: 29 Mar 2018, 13:53:32 UTC - in response to Message 1927083.

With a rocket that can deliver one G continuously you will reach the speed of light in one year if using Newton's Law of Motions.
Travel at 1G would take approximately 1 year + the distance in lightyears.
Proxima Centauri (4.2 light years) for example would take 5.2 years.
However Einstein made it more complicated.
Due to the time dilation effect, 1G acceleration should be sufficient to travel anywhere in our galaxy in less than a lifetime from the viewpoint of the traveler, but not the stationary observer.

One G acceleration during one year take a lot of energy. A LOT.
But the travellers will enjoy the trip feeling like back home on Earth.
ID: 1927091 ·
rob smith
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Message 1927094 - Posted: 29 Mar 2018, 14:25:10 UTC

Don't forget the deceleration at the other end of the journey, so +1g for one year, cruise for ~3.75 year then -1g for one year to get into an orbit around either the planet or a station keeping location for observation purposes.

There was some talk about "micro-g" accelerations to achieve fractional light speeds in a reasonable time, but again the energy required is substantial - one concept to be trialled is the use of solar sails, but that probably wouldn't work in the further reaches of the Solar system, never mind in the long interstellar part of the trip.
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ID: 1927094 ·
Bob DeWoody

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Message 1927141 - Posted: 29 Mar 2018, 20:03:41 UTC - in response to Message 1927094.

Don't forget the deceleration at the other end of the journey, so +1g for one year, cruise for ~3.75 year then -1g for one year to get into an orbit around either the planet or a station keeping location for observation purposes.

There was some talk about "micro-g" accelerations to achieve fractional light speeds in a reasonable time, but again the energy required is substantial - one concept to be trialled is the use of solar sails, but that probably wouldn't work in the further reaches of the Solar system, never mind in the long interstellar part of the trip.

It depends on how much you can accelerate with the sail while the sun has any affect, then you would coast most of the distance to the target star. When in the vicinity of the target star you could use the sail to decelerate depending on strength of that star's solar wind.

My biggest gripe with Star Trek and most other space movies trying to be somewhat scientifically accurate is the notion that when you shut down your engines you will eventually come to a stop. Stop relative to what? Everything in space is moving, some things faster than others but still moving. Most hated command on Star Trek "Full Stop" like you are on an ocean on earth.
Bob DeWoody

My motto: Never do today what you can put off until tomorrow as it may not be required. This no longer applies in light of current events.
ID: 1927141 ·
moomin

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Message 1927148 - Posted: 29 Mar 2018, 20:40:59 UTC - in response to Message 1927141.

Most hated command on Star Trek "Full Stop" like you are on an ocean on earth.
Scotty used this device:)

But I have thinking.
How did the Apollo missions succeed to stop at our moon?
The escape velocity from Earth is about 40,270 km/h, 25,020 mph.
That is real fast but somehow they landed safely.
Without so much jet propulsion to deaccelerate as far as I know.
Going back to Earth though is much easier.
ID: 1927148 ·
Bob DeWoody

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Message 1927255 - Posted: 30 Mar 2018, 4:29:39 UTC - in response to Message 1927148.

Most hated command on Star Trek "Full Stop" like you are on an ocean on earth.
Scotty used this device:)

But I have thinking.
How did the Apollo missions succeed to stop at our moon?
The escape velocity from Earth is about 40,270 km/h, 25,020 mph.
That is real fast but somehow they landed safely.
Without so much jet propulsion to deaccelerate as far as I know.
Going back to Earth though is much easier.

Landing on a planet or asteroid is an entirely different scenario. There you are stopped relative to the body you landed on. Going into orbit around a planet or a moon you are not stopping so the "assume standard orbit" command is logical.
Bob DeWoody

My motto: Never do today what you can put off until tomorrow as it may not be required. This no longer applies in light of current events.
ID: 1927255 ·
Stargate (S.A.)
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Message 1927264 - Posted: 30 Mar 2018, 5:29:03 UTC - in response to Message 1927255.

Most hated command on Star Trek "Full Stop" like you are on an ocean on earth.
Scotty used this device:)

But I have thinking.
How did the Apollo missions succeed to stop at our moon?
The escape velocity from Earth is about 40,270 km/h, 25,020 mph.
That is real fast but somehow they landed safely.
Without so much jet propulsion to deaccelerate as far as I know.
Going back to Earth though is much easier.

Landing on a planet or asteroid is an entirely different scenario. There you are stopped relative to the body you landed on. Going into orbit around a planet or a moon you are not stopping so the "assume standard orbit" command is logical.

Getting from Earth is one thing that border of atmosphere/space is another, once past it you can pretty much do as you please and for as long as you want, going into orbit one must factor in the speed of target and to maintain it.. Asteroid/Comet need to include spin/speed/rotation..
ID: 1927264 ·
rob smith
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Message 1927276 - Posted: 30 Mar 2018, 6:06:54 UTC

The term "All Stop" refers to stopping the engines, it does not refer to stopping the craft.

As for the Lunar landing, crudely Apollo was turned round so the main engine was facing the direction of travel, a burn to get them slow enough for Lunar orbit, then the lander was detached, and it used its own engine to slow to Lunar re-entry speed and then used to further reduce speed to a safe landing speed (almost zero relative to the Lunar surface)
Bob Smith
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ID: 1927276 ·
Stargate (S.A.)
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Message 1927284 - Posted: 30 Mar 2018, 7:09:50 UTC

We know this, but outside the Earths Gravity and influence you can do anything as long as you don't hit a planet or solid object..This is where light speed is flawed you hit your gone.. It's nice to watch on Star Trek say take it away but not that simple, all still needs a course a plot otherwise your toast..Same applies to the moon..
ID: 1927284 ·
Lynn
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Message 1930869 - Posted: 19 Apr 2018, 10:21:47 UTC - in response to Message 1927284.

The US space agency's Tess satellite has launched from Cape Canaveral in Florida on a mission to find thousands of new worlds beyond our Solar System.

The mission will survey a great swathe of stars, hoping to catch the dips in brightness that occur when orbiting planets traverse their faces.

Tess's goal is to compile a catalogue that other telescopes can then focus in on for more detailed analysis.

"Tess is equipped with four very sensitive cameras that will enable it to monitor nearly the entire sky," said George Ricker, the mission's principal investigator from the Massachusetts Institute of Technology, which leads the project.

http://www.bbc.com/news/science-environment-43790557
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ID: 1930869 ·
Michael Watson

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Message 1930910 - Posted: 19 Apr 2018, 15:57:43 UTC - in response to Message 1930869.

One interesting aspect of the TESS mission is that, unlike the Kepler Space Telescope, it will concentrate on the brightest and nearest stars. The interest in planets orbiting the nearest stars has been especially keen, as is shown by the large amount of attention payed to Proxima B, the planet of Proxima Centauri, the nearest star beyond the Sun.

We're currently limited in what ground-based telescopes can tell us, in follow-up observation of planets turned up by space telescopes. It should just be possible to characterize the atmospheres, and so, to some extent, the potential for life on any planets found around the nearer stars.
ID: 1930910 ·
Gordon Lowe
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Message 1930956 - Posted: 19 Apr 2018, 22:21:09 UTC - in response to Message 1930910.

It should just be possible to characterize the atmospheres

That boggles my mind.
The mind is a weird and mysterious place
ID: 1930956 ·
Lynn
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Message 1933260 - Posted: 2 May 2018, 20:09:21 UTC - in response to Message 1930956.

Exoplanet First! Helium Spotted in Bizarre Comet-Like World's Air

For the first time, astronomers have detected helium in the atmosphere of an alien world, a new study reports. The discovery shows that it's possible to probe the air of at least some exoplanetswithout launching a new space telescope dedicated to this endeavor, the researchers said.
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ID: 1933260 ·
William Rothamel

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Message 1933287 - Posted: 3 May 2018, 0:41:11 UTC

Its about time that those who claim to be Astro-biologists step up and state the percentage of found planets that are in the habitable zone. Furthermore, how many, as a percent, have a rocky mass in the range of a few earth masses, and then to define what other characteristics are needed for Intelligent life to form and thrive. If we do this then I don't think that we will have to listen to the braying about the abundance of intelligent life in our Galaxy.

I have posited: stabilizing moon, liquid water, Atmosphere, magnetic field, near circular orbit, and so on. What we have seen so far from astro-biologists are studies of life in extreme environments here on Earth. If we limit our interests to intelligent life; then I think that we need a different viewpoint. Would life on Europa or Titan turn out to be intelligent in the sense of being equal to Homo Sapiens?

I suppose it is significant to explore the possibility of any other type of life forms anywhere else in the Universe --However, I think that we could answer this question by doing a little better job of exploring on Mars.
ID: 1933287 ·
Gordon Lowe
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Message 1935929 - Posted: 16 May 2018, 20:29:34 UTC - in response to Message 1933287.

doing a little better job of exploring on Mars.

Well, I'm hoping they put together a sample-return mission in the near future.
The mind is a weird and mysterious place
ID: 1935929 ·
tullio
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Message 1936274 - Posted: 19 May 2018, 12:45:20 UTC

The TESS satellite has swung by the Moon and taken its first images of the sky. It should start its mission in June.
Tullio
ID: 1936274 ·
Gordon Lowe
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Message 1938471 - Posted: 6 Jun 2018, 17:20:06 UTC - in response to Message 1930956.

It should just be possible to characterize the atmospheres

That boggles my mind.

The PBS tv show, "NOVA Wonders", a companion to the well-known NOVA, had a recent episode entitled "Are We Alone?" that did a very good job illustrating how scientists are able to determine the atmospheres.
http://www.pbs.org/wgbh/nova/wonders/#are-we-alone
The mind is a weird and mysterious place
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Lynn
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Message 1941406 - Posted: 27 Jun 2018, 1:49:04 UTC - in response to Message 1938471.

WASP-127b is weird!
. An international team of astronomers has identified traces of metals and possible signs of water in one of the least dense exoplanets ever found, according to a new study.

https://www.space.com/41004-metals-water-huge-puffy-exoplanet-wasp-127b.html
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Message boards : SETI@home Science : Planet Hunters Report Record-Breaking Discovery, Search for other habitable planets