☯☼☯ SEO and Non-SEO (Science-Education-Omnilogy) Forum ☯☼☯

Non - SEO knowledge => UFO => Topic started by: SEO on February 12, 2021, 07:26:08 PM

Title: Astronomy Q&A
Post by: SEO on February 12, 2021, 07:26:08 PM



Q&A (questions and answers) about different astronomical (relating to astronomy) topics.
Title: The hottest planet
Post by: SEO on February 12, 2021, 07:31:29 PM

The hottest planet

Which planet is the hottest? The hottest planet (in our solar system) is Venus. And the hottest planet in the universe? So far we know about KELT-9b, which is the hottest known exoplanet (more about this very hot exoplanet -- https://www.jpl.nasa.gov/news/for-hottest-planet-a-major-meltdown-study-shows (https://www.jpl.nasa.gov/news/for-hottest-planet-a-major-meltdown-study-shows)).
Title: The smallest planet
Post by: SEO on February 13, 2021, 06:23:06 AM

The smallest planet

 Which is the smallest planet in our solar system? Mercury is the smallest planet over here. It is just a little bigger than Earth’s moon. It's also the innermost planet of the solar system. More about Mercury in Britannica: https://www.britannica.com/place/Mercury-planet (https://www.britannica.com/place/Mercury-planet).
Title: The most distant object orbiting our Sun
Post by: SEO on February 13, 2021, 06:56:32 AM

The most distant object orbiting our Sun

The most distant object orbiting our Sun? Well, the most distant known object in our solar system is called "Farfarout". It's a planetoid. (Planetoids are small celestial bodies that orbit the Sun.)
Title: Which planets have rings
Post by: Non-SEO on February 14, 2021, 01:52:50 AM

Which planets have rings?

Which planets in this solar system have rings? There are four: Jupiter, Saturn, Uranus, and Neptune are the 4 planets in our solar system that have rings. Saturn's rings are the most popular.
Title: The coldest planet
Post by: Non-SEO on February 15, 2021, 03:53:51 AM

Which is the coldest planet in our solar system?

Pluto was the planet furthest away from the Sun and also the coldest. But, Pluto was declassified as a planet in 2006 (and is now known as a dwarf planet). So, which one is the coldest planet in our Solar System now? There are 2 answers (according to how do you define "the coldest planet"): 1. Neptune has the coldest overall average temperature. 2. Uranus has the coldest temperature recorded.
Title: The highest mountain on Mars
Post by: Internet on February 22, 2021, 12:59:26 AM

The highest mountain on Mars

Which is the highest Mars' mountain? The highest mountain on Mars is called Olympus Mons. It is also the highest mountain in the entire solar system. Olympus Mons is about three times higher than Mt. Everest. :o
Title: How long would a trip to Mars take?
Post by: SEO on August 07, 2021, 03:11:15 AM

How long would a trip to Mars take?

Do you know how long would a trip to Mars take? A good answer and details over here: "How long does it take? It takes the Earth one year to orbit the Sun and it takes Mars about 1.9 years ( say 2 years for easy calculation ) to orbit the Sun. The elliptical orbit which carries you from Earth to Mars is longer than Earth's orbit, but shorter than Mars' orbit. Accordingly, we can estimate the time it would take to complete this orbit by averaging the lengths of Earth's orbit and Mars' orbit. Therefore, it would take about one and a half years to complete the elliptical orbit above ( solid and dashed parts! ). Since it would be nice to spend some time at Mars, we are only interested in the one way trip ( solid line ) which is half of the orbit, and would take half the time of the full orbit, or about nine months. So it takes nine months to get to Mars. It is possible to get to Mars in less time, but this would require you to burn your rocket engines longer, using more fuel. With current rocket technology, this isn't really feasible.

In the nine months it takes to get to Mars, Mars moves a considerable distance around in its orbit, about 3/8 of the way around the Sun. You have to plan ahead to make sure that by the time you reach the distance of Mar's orbit, that Mars is where you need it to be! Practically, this means that you can only begin your trip when Earth and Mars are properly lined up. This only happens every 26 months. That is there is only one launch window every 26 months.

After spending 9 months on the way to Mars, you will probably want to spend some time there. In fact, you MUST spend some time at Mars! If you were to continue on your orbit around the Sun, then when you got back to where you started, Earth would no longer be where you left it!

In order to get out of your elliptical orbit around the Sun, and into Mars orbit, you will again need to burn some fuel. If you want to explore the surface of Mars, you will also need fuel to get your lander off the surface of Mars. On the first trip to Mars, it is necessary to bring all of this fuel with you to Mars. ( Maybe someday we could manufacture rocket fuel on Mars ). In fact, you can only land a small part of the ship on Mars, because landing everything on the surface and lifting it off again would require enormous amounts of fuel. Therefore, you will probably leave part of the ship, including all the supplies for the trip home, orbiting Mars, while part of the crew goes to explore the surface.

Just like you have to wait for Earth and Mars to be in the proper postion before you head to Mars, you also have to make sure that they are in the proper position before you head home. That means you will have to spend 3-4 months at Mars before you can begin your return trip. All in all, your trip to Mars would take about 21 months: 9 months to get there, 3 months there, and 9 months to get back. With our current rocket technology, there is no way around this. The long duration of trip has several implications.

First, you have to bring enough food, water, clothes, and medical supplies for the crew in addition to all the scientific instruments you will want to take. You also have to bring all that fuel! In addition, if you are in space for nine months, you will need a lot of shielding to protect you from the radiation of the Sun. Water, and cement make good shielding but they are very heavy. All together, it is estimated that for a crew of six, you would need to 3 million pounds of supplies! The Shuttle can lift about 50,000 pounds into space, so it would take 60 shuttle launches to get all your supplies into space. In the history of the Shuttle, there have only been about 90 launches, and there are less than ten launches per year... So with the shuttle, it would take six years just to get the supplies into space. For this reason, you would probably need to develop a launch system that could lift more than 50,000 pounds into space. Even with a better launch vehicle, it is unlikely that you could launch the Mars mission all at once. You will have to launch it in several pieces and assemble them in orbit.

Second, you are going to be in space for an extended period of time, and there a physiological consequences of being weightless for long periods of time. For one, your muscles do not need to work as hard. In response to being used less, your muscles begin to shrink or atrophy. Remember, your heart is also a muscle, and pumping blood around your body is easier in the weightless environment of space, so your heart gets weaker as well. On an extended space voyage, your muscles might become so weak that it would be difficult for you to stand upright once you return to an environment where you are subject to gravity.

Just like your muscles have to do less work to move you around in space, your bones are not needed as much. The main function of your skeleton is to support the weight of your body. When you are weightless in space, your body realizes that the bones are not being used as much and they begin to lose calcium, and become more brittle. These are serious effects which may impair the ability of the astronauts to carry out experiments and tasks when they get to Mars, where they will be subjected to gravity again.

In order to study these physiological effects of long duration weightlessness, you need to do experiments on people who have been weightless for extended periods of time. Currently the Russian Mir space station is one place where astronauts can stay for extended periods of time, and research into these effect is ongoing. But since you will need to conduct many more experiments, and you will also need a place to assemble the mission, it will probably be necessary to construct a larger space station to be used as a staging ground for the mission to Mars." Source: https://image.gsfc.nasa.gov/poetry/venus/q2811.html (https://image.gsfc.nasa.gov/poetry/venus/q2811.html).
Title: How old is the universe?
Post by: Non-SEO on September 08, 2021, 01:33:35 AM

How old is the universe?

Some answers of the question "How old is the universe?" It's very old for sure.  :) Well, measurements made by NASA's WMAP spacecraft have shown that the universe is 13.7 billion years old (+ or - about 130,000 years). And another one: "Pushing the limits of its powerful vision, NASA's Hubble Space Telescope uncovered the oldest burned-out stars in our Milky Way Galaxy. These extremely old, dim "clockwork stars" provide a completely independent reading on the age of the universe.

The ancient white dwarf stars, as seen by Hubble, are 12-13 billion years old. Because earlier Hubble observations show that the first stars formed less than 1 billion years after the universe's birth in the big bang, finding the oldest stars puts astronomers well within arm's reach of calculating the absolute age of the universe.

Though previous Hubble research sets the age of the universe at 13-14 billion years based on the rate of expansion of space, the universe's birthday is such a fundamental and profound value that astronomers have long sought other age-dating techniques to cross-check their conclusions.

Globular clusters are the first pioneer settlers of the Milky Way. Many coalesced to build the hub of our galaxy and formed billions of years before the appearance of the Milky Way's magnificent pinwheel disk. Today 150 globular clusters survive in the galactic halo. The globular cluster M4 was selected because it is the nearest to Earth, so the intrinsically feeblest white dwarfs are still apparently bright enough to be picked out by Hubble." (Source: https://www.nasa.gov/multimedia/imagegallery/image_feature_734.html (https://www.nasa.gov/multimedia/imagegallery/image_feature_734.html))