- Astronomers have discovered thousands of $4, or worlds beyond the solar system.
- In June, researchers announced they'd logged the 4,000th such planet into a $4 catalog. The first was found in 1992.
- Two artists have illustrated all of those discoveries in 60 seconds using an incredible animated $4 and timeline of the data.
- Some of the exoplanets $4.
- $4.
Earth is not alone, and a stunning new $4 created using NASA data beautifully illustrates that point.
There may be $4 of other planets in our galaxy, the Milky Way (which itself is one of hundreds of billions of $4 in the $4). But finding such extrasolar planets, or exoplanets, is not easy - even when they're relatively close by.
In fact, it takes more than four years for $4 from the nearest star to our solar system. Meanwhile, exoplanets are both small and dim, and $4 is a 100,000 light-year-wide haystack for astronomers to scour.
Despite their long odds, however, astronomers have logged thousands of exoplanets since a team confirmed the existence of the first one $4. This June, in fact, marked a milestone: researchers logged the 4,000th discovery in an ever-growing NASA $4.
To celebrate the achievement, two artists pulled all of that data and compiled it into a short animated map and timeline called "4000 Exoplanets," shown below.
The animation was created by artist $4 and scored by musician $4, who both work with a science-art outreach project called System Sound. The short film was published to YouTube on Sunday and $4 on Wednesday by NASA's $4.
What the animated exoplanet timeline shows
The video shows a flattened map of the 360-degree night sky as seen from Earth. The bright band of stars in the center is a cross-cut view of the Milky Way; it looks this way because our solar system drifts within the spiral galaxy.
NASA; Business Insider
Each circle that appears represents a confirmed exoplanet discovery. The main method used to find each world is shown as one of seven colors.
For example, purple circles show a planet found by its transit, or passage in front of a parent star; this is detectable because it causes periodic, subtle drops in the parent star's brightness level relative to Earth. Pink, meanwhile, shows distant worlds that were located because their gravitational pull was strong enough to make their star "wiggle" sufficiently for astronomers to detect.
Read more: $4
The pace of discoveries in the 60-second timeline starts off slowly, with only about 70 extrasolar worlds located in the first decade of discoveries. That's because finding and confirming the existence of exoplanets was extraordinarily difficult without advanced tools and resources.
But as funding grows, techniques improve, more ground telescopes help with the search, and new space observatories launch into space, the rate at which exoplanets have been found has increased. The pace of discovery really exploded after 2009, when NASA launched its Kepler Space Telescope.
Kepler focused its search on a small patch of the sky and used the transit method of exoplanet detection on 150,000 stars. This is why, in the animation, a big purple blob suddenly begins to appear around 2010 (at top-left) and the exoplanet count skyrockets.
NASA $4, but in April 2018, NASA $4 a similar planet hunter called the $4.
TESS is expected to scan 200,000 nearby stars across 85% of the night sky, revealing thousands of additional planets. Below is an animation of TESS' planned survey.
Around $4, creating promising targets for more detailed observations by telescopes that can image objects much deeper in space.
The $4 may come from enormous ground-based observatories, including the $4, which are poised to come online starting in the mid-2020s. Astronomers hope such telescopes can take raw exoplanet discoveries a step further by picking up light from their atmospheres - and potentially "sniffing" out biosignatures that may indicate the presence of alien life.