# How does nasa find planets light years away?

In order to find planets outside of our solar system, or exoplanets, astronomers use a variety of methods. One method is to look for planets orbiting a star using the transit method. This method relies on a star’slightdimming ever so slightly as an orbiting planet transits, or crosses, in front of the star from our perspective. Although this dip in the star’s brightness is tiny, just a fraction of a percent, NASA’s Kepler space telescope is able to measure it.

Summary

Nasa uses a process called spectroscopy to find planets light years away. Spectroscopy is the study of how light interacts with matter. By looking at how light from a star is affected by the presence of a planet, astronomers can infer the planet’s size, mass, and orbit.

## How do scientists know how many light-years away?

A light-year is a unit of distance used to measure extremely large distances. It is defined as the distance that light can travel in one year. In a vacuum, light travels at a speed of 670,616,629 mph (1,079,252,849 km/h). To find the distance of a light-year, you multiply this speed by the number of hours in a year (8,766). The result is that one light-year equals 5,878,625,370,000 miles (95 trillion km).

Transits are a powerful tool for finding exoplanets, and NASA has used them to great effect. More than 78 percent of the 3,700 confirmed exoplanets have been discovered using transits. The last major exoplanet search spacecraft, Kepler, found over 2,600 exoplanets by watching for transits. Most of them were orbiting distant (read: dim!) stars 300 to 3,000 light-years from Earth.

Transits are relatively easy to observe, and they can provide a wealth of information about an exoplanet. For example, transits can be used to determine a planet’s size, density, and orbital period. They can also be used to search for an exoplanet’s atmosphere and even for signs of life.

There are some drawbacks to using transits to find exoplanets, however. First, transits can only be used to find planets that orbit in front of their star from our perspective. Second, transits can only be used to find planets that are relatively close to their star (i.e., within a few hundred light-years). But despite these limitations, transits have been an invaluable tool in the search for other worlds.

### How do we discover planets that are millions of miles away

The planetary transit method is a way to detect planets by observing them as they pass in front of their parent star. This is possible because the planets block some of the star’s light when they pass in front of it, and this can be detected by sensitive instruments. The Kepler space telescope has used this method to find most of the exoplanets that we know today.

The universe is constantly expanding, and as it does, the light from distant objects gets stretched. This means that the light we see from these objects is actually from a time when they were much closer to us. We can see objects up to 461 billion light-years away precisely because of the expanding universe.

## How do we know universe is 13.8 billion years old?

We do not know the exact age of the universe, but we believe that it is around 13 billion years – give or take a few billion. Astronomers estimate the age of the universe in two ways: (a) by looking for the oldest stars; and (b) by measuring the rate of expansion of the universe and extrapolating back to the Big Bang.

Space telescopes have found thousands of planets by observing “transits,” the slight dimming of light from a star when its tiny planet passes between it and our telescopes Other detection methods include gravitational lensing, the so-called “wobble method.”

## How do we know planets exist?

Astronomers use two main methods to detect planets orbiting other stars. The first is called transit photometry and involves pointing a telescope at a star and looking for the regular, slight dimming in its light caused by a planet orbiting in front of it. The other is the radial velocity technique, which involves measuring the Doppler shift of a star’s light caused by the star’s motion in response to the gravitational pull of an orbiting planet.

This is amazing news! I am so excited that there may be another planet out there that is so similar to our own. This gives me hope that one day we may be able to find a planet that is habitable for humans. I can’t wait to see what further research is done on this topic.

### What’s beyond our galaxy

Other galaxies exist beyond our own galaxy, the Milky Way. The nearest galaxy to our own is Andromeda, which is on a collision course with the Milky Way. Our galaxy is part of a group of 30 galaxies called the Local Group.

Pluto was only discovered in 1930, which is relatively recent in terms of the history of our solar system. Because it is so far away from Earth, it is very difficult to observe. Even with the largest telescopes, it is only a dim speck of light.

## Is Earth the only planet with life?

Even though there are thousands of exoplanets that have been confirmed by telescopes, Earth is still the only planet known to host life. This is because Earth is the only planet in the solar system that has the right conditions for life to exist. Conditions on Earth are just right for water to exist in liquid form, for example, which is essential for life as we know it. Additionally, Earth has a protective atmosphere that shields us from harmful radiation from the Sun.

There are many other factors that make Earth a unique and special planet, but the main reason why it is the only planet known to host life is because it is the only planet in the solar system with the right conditions for life to exist. With advances in technology, we may one day find another planet with the same conditions as Earth, but for now, our planet is still one of a kind.

However, there are a few ways in which we could see a galaxy that far away. One possibility is that the light from this galaxy has been magnified by an extremely powerful gravitational lens. Another possibility is that this galaxy is actually much closer to us than 15 billion light-years, but is moving away from us so quickly that its light is stretched to appear 15 billion light-years away.

### Why can t we see past 14 billion light years

We will never see the light from objects that are currently more than 15 billion light years away, because the universe is continuing to expand. As the universe expands, the space between objects also increases. This means that the light from distant objects takes longer to reach us, and eventually we will no longer be able to see them.

The expanding Universe is one of the key cosmological observations which supports the Big Bang theory. The theory states that the Universe began from a single, extremely dense and hot point, known as the singularity. As the Universe expanded and cooled, the various particles which make up the Universe began to form.

The fact that space itself is expanding means that new space is constantly being created. This is why the Universe appears to be getting bigger. The galaxies, groups and clusters of galaxies are all bound together by gravity, but as space expands, they are getting further and further apart.

## What was there before the universe?

In the beginning, there was an infinitely dense, tiny ball of matter. Then, it all went bang, giving rise to the atoms, molecules, stars and galaxies we see today. Or at least, that’s what we’ve been told by physicists for the past several decades.

HD 140283, also known as the “Methuselah star”, is a star that we have observed for almost 100 years. However, when measuring its age, scientists reached the value of 14.27 billion years. This value is so old that it means the star is almost as old as the universe itself!

## Warp Up

Nasa uses a process called radial velocity to find planets light years away. This process looks for a star’s wobble caused by the gravity of an orbiting planet. The larger the planet, the more pronounced the wobble. This method has been used to find thousands of planets outside our solar system.

Nasa finds planets light years away by looking for changes in starlight. When a planet passes in front of a star, it blocks some of the star’s light. This causes the star to look dimmer for a short time.

Thelma Nelson is passionate about space exploration and the possibilities it holds. She has been an avid supporter of SpaceX and other private space companies, believing that these organizations have the potential to unlock the mysteries of the universe. She has been a vocal advocate for more investment in research and development of space technology.