We Just Identified More Than 200 New (Potential) Planets
The Kepler space telescope is our first mission capable of identifying Earth-size planets around other stars. On Monday, June 19, 2017, scientists from many countries gathered at our Ames Research Center to talk about the latest results from the spacecraft, which include the identification of more than 200 potential new worlds! Here’s what you need to know:
We found 219 new planet candidates.
All of these worlds were found in a patch of sky near the Cygnus constellation in our Milky Way galaxy. Between 2009 and 2013, Kepler searched more than 200,000 stars in the region for orbiting planets. The 219 new planet candidates are part of the more than 4,000 planet candidates and 2,300 confirmed planets Kepler has identified to date.
Ten of these worlds are like our own.
Out of the 219 new planet candidates, 10 are possibly rocky, terrestrial worlds and orbit their star in the habitable zone – the range of distances from a star where liquid water could pool on the surface of a rocky planet.
Small planets come in two sizes.
Kepler has opened up our eyes to the existence of many small worlds. It turns out a lot of these planets are either approximately 1.5 times the size of Earth or just smaller than Neptune. The cool names given to planets of these sizes? Super Earths and mini-Neptunes.
Some of the new planets could be habitable.
Water is a key ingredient to life as we know it. Many of the new planet candidates are likely to have small rocky cores enveloped by a thick atmosphere of hydrogen and helium, and some are thought to be ocean worlds. That doesn’t necessarily mean the oceans of these planets are full of water, but we can dream, can’t we?
Other Earths are out there.
Kepler’s survey has made it possible for us to measure the number of Earth-size habitable zone planets in our galaxy. Determining how many planets like our own that exist is the big question we’ll explore next.
Milkyway above Lake Tahoe. We gazed over the still water as a thunderstorm loomed in the distance. Lightning lit up the purple clouds to the right. It’s calming to feel so small under the vast and wondrous sky.
When it comes to galaxies, our home, the Milky Way, is rather neat and orderly. Other galaxies can be much more chaotic. For example, the Markarian 573 galaxy has a black hole at its center which is spewing beams of light in opposite directions, giving its inner regions more of an hourglass shape.
Our scientists have long been fascinated by this unusual structure, seen above in optical light from the Hubble Space Telescope. Now their search has taken them deeper than ever — all the way into the super-sized black hole at the center of one galaxy.
So, what do we think is going on? When the black hole gobbles up matter, it releases a form of high-energy light called radiation (particularly in the form of X-rays), causing abnormal patterns in the flow of gas.
Let’s take a closer look.
Meet Markarian 573, the galaxy at the center of this image from the Sloan Digital Sky Survey, located about 240 million light-years away from Earth in the constellation Cetus. It’s the galaxy’s odd structure and the unusual motions of its components that inspire our scientists to study it.
As is the case with other so-called active galaxies, the ginormous black hole at the center of Markarian 573 likes to eat stuff. A thick ring of dust and gas accumulates around it, forming a doughnut. This ring only permits light to escape the black hole in two cone-shaped regions within the flat plane of the galaxy — and that’s what creates the hourglass, as shown in the illustration above.
Zooming out, we can see the two cones of emission (shown in gold in the animation above) spill into the galaxy’s spiral arms (blue). As the galaxy rotates, gas clouds in the arms sweep through this radiation, which makes them light up so our scientists can track their movements from Earth.
What happens next depends on how close the gas is to the black hole. Gas that’s about 2,500 light-years from the black hole picks up speed and streams outward (shown as darker red and blue arrows). Gas that’s farther from the black hole also becomes ionized, but is not driven away and continues its motion around the galaxy as before.
What caused this outburst of this star named V838 Mon? For reasons unknown, this star’s outer surface suddenly greatly expanded with the result that it became the brightest star in the entire Milky Way Galaxy in January 2002. Then, just as suddenly, it faded. A stellar flash like this had never been seen before – supernovas and novas expel matter out into space.
Although the V838 Mon flash appears to expel material into space, what is seen in the above GIF from the Hubble Space Telescope is actually an outwardly moving light echo of the bright flash.
In a light echo, light from the flash is reflected by successively more distant rings in the complex array of ambient interstellar dust that already surrounded the star. V838 Mon lies about 20,000 light years away toward the constellation of the unicorn (Monoceros), while the light echo above spans about six light years in diameter.