Space Stuff and Launch Info

[ISamson]

Can we see the Halley's Comet in our near future?

Probably.
In what country? Australia, Perth?
I don't know. Look it up.

 

[Borg]

Can we see the Halley's Comet in our near future?

No. It won't be back again until 2061. See the Wiki article on Halley's Comet for more info.

 

[Copernicus45]

Do you think another existing universe could have a different structure for nature from our structure?
For example instead of the one proton equalling the electron, it would have two electrons or more equalling a single proton.
Is it even possible to imagine?

 

[Borg]

@Copernicus45, please read the forum rules under the INFO tab at the top of the page. Physics Forums is for discussing mainstream science. Personal, or made-up theories are not allowed.

 

[mfb]

Probably.
In what country? Australia, Perth?
I don't know. Look it up.

Comets, if they are visible at all, are always visible from more than half of Earth‘s surface, often from nearly everywhere on Earth (if the comet is not too far away from the ecliptic).

Do you think another existing universe could have a different structure for nature from our structure?
For example instead of the one proton equalling the electron, it would have two electrons or more equalling a single proton.
Is it even possible to imagine?

Please don’t post off-topic questions here. Changing electric charges would often make quantum field theory inconsistent.

 

[Copernicus45]

Is the moon orbital around the Earth the same always?
Would the Sun's gravitational attraction might affect the moon's orbital when it is between Earth and the Sun.

 

[Stavros Kiri]

Here's something interesting (+some interesting Mars aurora videos will follow, later on):
https://www.physicsforums.com/threa...ther-update-thread.923468/page-3#post-5859428

 

[mfb]

Both SpaceX launches were successful - 15 so far this year, and 5 more planned.

As comparison: The rest of the US had 7 launches. Russia had 15, China 10, and all other countries had lower numbers. In total there were 66 launches this year.
SpaceX is rapidly increasing its market share, last year it did 8 out of 85 launches.

 

[Stavros Kiri]

Asteroid Approaching! Watch Slooh Flyby Webcast Tonight

 

[1oldman2]

SpaceX is rapidly increasing its market share,

The competition seems to be noticing, everyone is using SpaceX as "The Benchmark" to beat, (or at least compete with). Come to think of it, I could have titled the thread "SpaceX and stuff".
http://spacenews.com/ils-says-proton-medium-will-compete-head-to-head-with-falcon-9/

 

[1oldman2]

There is also a more specialized (but not limited to only) thread:

True, I was actually going to just post the home page of NTRS https://ntrs.nasa.gov/search.jsp as a useful collection of reports, data etc. but I couldn't resist linking the Solar Physics page as a sort of "hook" to get folks to look around the site.

 

[Stavros Kiri]

True, I was actually going to just post the home page of NTRS https://ntrs.nasa.gov/search.jsp as a useful collection of reports, data etc. but I couldn't resist linking the Solar Physics page as a sort of "hook" to get folks to look around the site.

References and links to Solar Physics is of course (IMO) part of this more general thread too. Sun is both 'space' and 'stuff' ...

 

[rootone]

Is the moon orbital around the Earth the same always?
Would the Sun's gravitational attraction might affect the moon's orbital when it is between Earth and the Sun.

We know by measurement that the Moon is very slowly becoming more distant from Earth, a few centimeters a year.
The Sun doesn't have much to do with that, although it might contribute to Earth/Moon orbital dynamics in a small way.
Jupiter possibly does too.

 

[ISamson]

Might be interesting...
https://www.space.com/38545-moon-photobombs-sun-nasa-sdo-image.html

 

[SciencewithDrJ]

Fluids in microgravity. Unintuitive behaviour.

 

[jayzun]

The reason I made an account is to ask about the effect of gravity from an extra planet hiding behnd the sun. I think that if this was the case we would see much great impacts¿ say like the tides. Would they not be extremely high and low? Nonstop quakes that would be felt across the world?

 

[mfb]

The reason I made an account is to ask about the effect of gravity from an extra planet hiding behnd the sun. I think that if this was the case we would see much great impacts¿ say like the tides. Would they not be extremely high and low? Nonstop quakes that would be felt across the world?

Please open new threads for questions like these.

Tidal effects depend strongly on the distance between the objects. A planet-scale mass, more distant than the Sun, would have a completely negligible effect on tides. Venus and Mars have much larger effects (as they come closer), and they are completely negligible already. In addition, if it would always be in the direction of Sun, it would just be added to the Sun's effect on the tides - just a several million times smaller.

We would see an effect on orbits, however - the orbital period of Earth and all outer planets would be shorter than expected, and the orbits of Mercury, Venus and Mars would be perturbed when they are close to this planet. This would be immediately obvious with the precision of today's measurements.
Such an additional planet wouldn't be in a stable orbit either, it couldn't stay there for any relevant timescale.

Oh, and we have multiple space probes which would have seen anything there.

 

[Astronuc]

Just passing through - A/2017 U1

A small, recently discovered asteroid -- or perhaps a comet -- appears to have originated from outside the solar system, coming from somewhere else in our galaxy. If so, it would be the first "interstellar object" to be observed and confirmed by astronomers.

This unusual object - for now designated A/2017 U1 - is less than a quarter-mile (400 meters) in diameter and is moving remarkably fast.

https://www.jpl.nasa.gov/news/news.php?feature=6983

A/2017 U1 was discovered Oct. 19 by the University of Hawaii's Pan-STARRS 1 telescope on Haleakala, Hawaii, during the course of its nightly search for near-Earth objects for NASA.

 

[1oldman2]

Juno is paying off again.
https://www.nature.com/articles/s41...mWD8=&tracking_referrer=www.universetoday.com

 

[Stavros Kiri]

https://www.space.com/38673-moon-occults-bulls-eye-star-aldebaran-tonight.html

 

[1oldman2]

https://www.space.com/38673-moon-occults-bulls-eye-star-aldebaran-tonight.html

A few more highlights for November. https://www.jpl.nasa.gov/video/details.php?id=1505

 

[mfb]

Some spaceflight events for the rest of the year:

• 14 November (update, was 10 November before) - Delta II launch of a few small satellites. If successful, it will be the 99th consecutive success of Delta II, with one more launch planned for September 2018 before the rocket is retired.
• 16 November - Falcon 9 launch of the mysterious "Zuma". It is known that Northrop Grumman built the satellite and that some US government agency wants to have it in low Earth orbit, apart from that nothing is known - not even which government agency is responsible.
• 4 December - Falcon 9 launch with a refurbished first stage, the fourth time a booster is reused. The mission delivers cargo to the ISS - with a Dragon capsule that was previously flown in 2015, the second time a Dragon is reused.
• 7 December - Angola joins the (long) list of countries with satellites
• 23 December - Falcon 9 launch with another refurbished first stage, the fifth time a booster is reused. Delivering 10 Iridium satellites to orbit.
• 29 December (maybe) - maiden flight of Falcon Heavy. The two side boosters are from earlier Falcon 9 flights, making them the sixth and seventh reused boosters. SpaceX aims for this date, but there will be extensive tests of the rocket during December, the launch date will depend on the outcome of these tests. If successful, it will be the largest rocket to reach orbit since the Energia/Buran flight in 1988, and the rocket with the second most useful payload after Saturn V.
• December (maybe) - second launch of Electron after a failure earlier this year. If successful, it will be the second-smallest rocket to ever reach orbit (after Lambda 4S) and the smallest liquid-fuel rocket to reach orbit.

The first re-flight of a Falcon 9 booster was in March this year, by the end of the year we could have 7 (if Falcon Heavy makes it in December). SES had two of them, Bulsatcom got another one, NASA agreed to use one (and potentially more), Iridium will get two, and SpaceCom wants one. NASA, SES and Iridium are the largest three customers. Less than two years after the first landing and less than a year after the first reuse it looks like it is getting routine. A big reduction in new boosters means SpaceX can focus more on second stages and increase the launch rate even more. Currently they launch nearly as much as all of Russia (16 vs. 17 this year).

 

[Stavros Kiri]

https://www.space.com/38673-moon-occults-bulls-eye-star-aldebaran-tonight.html

Saw it! ... Cool!

 

[1oldman2]

This is worth zooming in, note the red and blue noise in the bottom left corner.

https://www.nasa.gov/image-feature/jpl/pia21970/jupiter-s-stunning-southern-hemisphere
"The image was taken on Oct. 24, 2017 at 11:11 a.m. PDT (2:11 p.m. EDT), as Juno performed its ninth close flyby of Jupiter. At the time the image was taken, the spacecraft was 20,577 miles (33,115 kilometers) from the tops of the clouds of the planet at a latitude of minus 52.96 degrees. The spatial scale in this image is 13.86 miles/pixel (22.3 kilometers/pixel)."

 

[ISamson]

New habitable exoplanet found!
https://www.space.com/38782-possibly-earth-like-alien-planet-ross-128b.html

DARPA: Space warfare defence lab development.
https://www.space.com/38775-bae-systems-darpa-3d-space-warfare-lab.html

 

[Borg]

I just can't get excited about newly discovered planets that are orbiting red dwarfs. Tidal locking and solar flares that sweep the planet regularly don't make these great candidates for life even if they are 'habitable'. When JWST comes online and starts finding habitable planets farther out, that will be a different story.

 

[mfb]

Maybe habitable. And keep in my mind that Venus is a planet in the habitable zone as well.
In addition, only a lower mass limit is known, the planet could be much heavier. We’ll see more once the megatelescopes are running.

 

[1oldman2]

A piece that's not only timely but relevant.
https://www.nasa.gov/feature/jpl/our-living-planet-shapes-the-search-for-life-beyond-earth

 

[1oldman2]

https://spaceflightnow.com/2017/12/07/rocket-lab-pushes-back-second-electron-launch-by-one-day/

 

[mfb]

Now Dec 9, 01:30-05:30 UTC. This post was made Dec 7 12:55 UTC or 36.5 hours before the earliest launch time.
Edit: Shifted to December 11.

Other updates relative to the November schedule: Mainly delays.

• Delta II launched successfully. 99 successes in a row, one more launch planned for 2018.
• Zuma was on the launch pad already when an issue with the payload fairing for another customer appeared. Apparently a serious one, the rocket was taken off the launch pad and the launch is now scheduled for January 5, nearly two months delayed. It will launch from a different launch pad as well - normally an administrative nightmare, but whatever government agency is behind the payload could speed that up apparently.
• SpaceX CRS-13, the ISS resupply mission, is now planned for December 12, 16:46 UTC. It will still be a large recycling mission, both the first stage and the Dragon capsule were in space already.
• Just 5 days later a Soyuz will launch a Russian, a Japanese and a US astronaut to the ISS.
• The Iridium launch for December 23 is still planned for that date, surprisingly. SpaceX reuses a booster from an earlier flight for the same customer.
• Angola's first satellite got shifted to December 26.
• No Falcon Heavy launch this year, although we might get the static fire (full engine test on the ground) this month. January 2018 is the current estimate. The payload will be Elon Musk's private Tesla Roadster, and the target orbit crosses the orbit of Mars. No, this is not a joke.
• The Japanese SS-520 is back. After a launch failure in January, another flight is planned for December 28. If successful, it will be the smallest and lightest rocket to make it to orbit, with a length of 9.5 meters, a diameter of 52 cm and a mass of just 2.6 tonnes.

No Google Lunar X-Prize rocket. The teams all seem to go for the latest possible launch date in March.
No Chinese Lunar sample return mission.

SpaceX launched about as many rockets as all of Russia in 2017. For 2018 they aim at ~30 launches in 2018, more than any country (including the US without SpaceX).