exoplanet Archives

December 8, 2021December 8, 2021 by Evan Gough

TESS Finds a New Mars-Sized Planet (With the Density of Mercury)

An artist's illustration of a hypothetical exoplanet orbiting a red dwarf. Image Credit: NASA/ESA/G. Bacon (STScI)

Some planets orbit their stars so closely that they have extremely high surface temperatures and extremely rapid orbits. Most of the ones astronomers have found are Hot Jupiters— planets in the size range of Jupiter and with similar compositions as Jupiter. Their size and proximity to their star make them easier to spot using the transit method.

But there’s another type of planet that also orbits very close to their stars and has extremely high surface temperatures. They’re small, rocky, and they orbit their star in less than 24 hours. They’re called ultra-short-period (USP) planets and TESS found one that orbits its star in only eight hours.

And the planet’s density is almost equivalent to pure iron.

October 7, 2021October 7, 2021 by Evan Gough

An Exoplanet Reaches 2400 C in One Hemisphere. Does it Really Rain Iron?

This artist's illustration shows the fiery exoplanet WASP-76b. Previous study shows the planet rains iron it's so hot. Now astronomers have detected barium in its atmosphere. Image Credit: ESO/M. Kornmesser

WASP-76b is an ultra-hot Jupiter about 640 light-years away from Earth in the constellation Pisces. A few years ago it gained notoriety for being so hot that iron falls as rain. It’s tidally locked to its star, and the planet’s star-facing hemisphere can reach temperatures as high as 2400 Celsius, well above iron’s 1538 C melting point.

Scientists have been studying the planet since its discovery in 2013, and new evidence suggests that it’s even hotter than thought. But, almost disappointingly, there might be no iron rain after all.

June 25, 2021June 25, 2021 by Matt Williams

Aliens in 2,034 Nearby Star Systems Could use the Transit Method to see Earth

For centuries, human beings have speculated about the existence of planetary systems (much like our own) orbiting other stars. However, it has only been in the past few decades that scientists have been able to detect and study these distant worlds. To date, astronomers have used various methods to confirm the existence of 4,422 extrasolar planets in 3,280 star systems, with an additional 7,445 candidates awaiting confirmation.

Naturally, this raises some questions. If there is intelligent life out there that has similar capabilities to our own – and the same burning sense of curiosity – could it be watching us too? Equally important is the question of how many of be able to detect us. According to new research conducted by a team from Cornell and the American Museum of Natural History, there are 2,034 star systems within 326 light-years of Earth that would be watching us right now!

June 14, 2021June 14, 2021 by Evan Gough

Astronomers Have Found the Perfect Exoplanet to Study Another World’s Atmosphere

An artist's rendering of TOI-1231 b, a Neptune-like planet about 90 light years away from Earth. Credit: NASA/JPL-Caltech

TESS (Transiting Exoplanet Survey Satellite) has found a new planet, and the discovery of this sub-Neptune exoplanet has scientists excited about atmospheres. The combination of the planet’s size, its thick atmosphere, and its orbit around a small M-class star close to Earth provides researchers with an opportunity to learn more about exoplanet atmospheres. We’re getting better and better at finding exoplanets, and studying their atmospheres is the next step in understanding them as a whole.

May 30, 2021May 30, 2021 by Andy Tomaswick

Exoplanet Surveys are Leaning Towards the Possibility That our Solar System is… Normal

One of the unspoken caveats of most exoplanet discovery missions is that they only operate for a few years. Such a short observing window means there are planets with longer orbital periods, usually further out from the star, that those surveys would completely miss. Knowing this would be a problem, a team of astronomers arranged the California Legacy Survey three decades ago in order to monitor as many stars as possible for as long a time as possible. Recently they released their first results, which show solar systems that are surprisingly like our own.

April 3, 2021April 3, 2021 by Andy Tomaswick

TESS has Found 2,200 Potential Exoplanets so far

Exoplanetology has been on a tear recently. This is largely due to an abundance of data collected by a new generation of satellites, one of which is the Transiting Exoplanet Survey Satellite (TESS). Now the project has reached a new milestone with another release of data – 2,200 planet candidates collected, far surpassing the 1,600 expected candidates in the mission’s first two years. Now comes a potentially even more daunting task – following up with each of them.

March 8, 2021March 8, 2021 by Matt Williams

Gliese 486b is a Hellish World With Temperatures Above 700 Kelvin

In the past two and a half decades, astronomers have confirmed the existence of thousands of exoplanets. In recent years, thanks to improvements in instrumentation and methodology, the process has slowly been shifting from the process of discovery to that of characterization. In particular, astronomers are hoping to obtain spectra from exoplanet atmospheres that would indicate their chemical composition.

This is no easy task since direct imaging is very difficult, and the only other method is to conduct observations during transits. However, astronomers of the CARMENES consortium recently reported the discovery of a hot rocky super-Earth orbiting the nearby red dwarf star. While being extremely hot, this planet has retained part of its original atmosphere, which makes it uniquely suited for observations using next-generation telescopes.

November 16, 2020November 16, 2020 by Matthew Cimone

There are Planets So Close to Their Stars That They Have Magma Oceans 100km Deep and Winds that Go 8000 km/h

Artist's impression of a Lava World. The exoplanet K2-141b is so close to its host star that it likely has magma oceans and surface temperatures over 3000 degrees. c. ESO

200 light years away, “super earth” exoplanet K2-141b orbits a star so closely that its “year” is only 7 hours long. Not its day…its YEAR! K2-141b orbits a mere million kilometers from the fiery surface of its star. Earth is 150 million km from our Sun. Even Mercury, the planet closest to our Sun, is never less than 47 million km. Standing on the surface of K2-141b you’d look up at an orange star that filled fifty degrees of the sky appearing a hundred times wider than our Sun appears in Earth’s sky. It would be a giant blazing orb so bright that its light shines two thirds of the way around the entire planet unlike Earth’s two day/night halves. Of course, the surface you’re standing on wouldn’t be much of a surface at all – it would be an ocean of liquid hot magma.

Artist’s impression of a close orbiting exoplanet around a star. c. ESO

September 17, 2020September 17, 2020 by Evan Gough

James Webb Will Look for Signs of Life on Planets Orbiting Dead Stars

A planet orbiting a small star produces strong atmospheric signals when it passes in front, or “transits,” its host star, as pictured above. White dwarfs offer astronomers a rare opportunity to characterize rocky planets. Image Credit: Jack Madden/Carl Sagan Institute

Can the galaxy’s dead stars help us in our search for life? A group of researchers from Cornell University thinks so. They say that watching exoplanets transit in front of white dwarfs can tell us a lot about those planets.

It might even reveal signs of life.

August 12, 2020 by David Dickinson

Hubble Examines Earth’s Reflection as an ‘Exoplanet’ During a Lunar Eclipse

What would we look for in a distant exoplanet in the hunt for Earth-like worlds, and perhaps life? A recent observation carried out by the Hubble Space Telescope found tell-tale signatures from our home planet by looking at a familiar source under extraordinary circumstances: Earth’s Moon, during a total lunar eclipse.