BREAKING NEWS WATCH LIVE: Verdict being announced at murder trial over George Floyd's death Full Story

There are at least 300 million potentially habitable planets in our galaxy, NASA finds

Our galaxy is filled with potentially habitable planets -- at least 300 million of them, according to NASA.The US space agency's Kepler Space Telescop...

Posted: Nov 6, 2020 8:28 PM

Our galaxy is filled with potentially habitable planets -- at least 300 million of them, according to NASA.

The US space agency's Kepler Space Telescope spent nine years on a planet-hunting mission, successfully identifying thousands of exoplanets in our galaxy before running out of fuel in 2018. But the original mission's core question remained: how many of these planets are habitable?

Scientists around the world pored over Kepler's data for years -- and they think they've found the answer. According to research released in The Astronomical Journal, there are roughly 300 million potentially habitable worlds in our galaxy, meaning rocky planets capable of supporting liquid water on their surface.

That figure is a rough estimate on the conservative side, and "there could be many more," said NASA in a news release. Some of these planets could be close enough to be considered "interstellar neighbors" -- the closest is around 20 light-years away.

"Kepler already told us there were billions of planets, but now we know a good chunk of those planets might be rocky and habitable," said NASA researcher and lead author Steve Bryson in the release.

"Though this result is far from a final value, and water on a planet's surface is only one of many factors to support life, it's extremely exciting that we calculated these worlds are this common with such high confidence and precision."

The study was a global collaboration between NASA scientists who worked on the Kepler mission, and researchers from international agencies ranging from Brazil to Denmark.

How they did it

There are about 100 to 400 billion stars in our Milky Way galaxy, according to NASA estimates. Every star in the sky probably hosts at least one planet -- meaning there are likely trillions of planets out there, of which we have only discovered and confirmed a few thousand.

A lot of factors that influence whether a planet can support life, including its atmosphere and chemical composition. But to narrow down the trillions, the researchers in this study focused on a few basic requirements.

They looked for stars similar to our own Sun in age and temperature, so it wouldn't be too hot or active. They also looked for exoplanets with a similar radius to Earth, and singled out those that were likely to be rocky.

They also took into consideration each planet's distance from its star -- too close and the heat could vaporize any water, too far and any water could freeze.

A habitable planet needs to be in the "just right" zone, or the so-called Goldilocks zone, to support liquid water on its surface.

Previous estimates of the number of habitable planets did not reflect how a star's temperature and energy could be absorbed by its planets, said the NASA release. But this time, scientists were able to factor temperature into their analysis, thanks to additional data gathered by the European Space Agency's Gaia mission, which is charting a three-dimensional map of our galaxy.

"We always knew defining habitability simply in terms of a planet's physical distance from a star, so that it's not too hot or cold, left us making a lot of assumptions," said NASA scientist and study author Ravi Kopparapu in the release.

"Gaia's data on stars allowed us to look at these planets and their stars in an entirely new way."

After calculating these factors, researchers used a conservative estimate that 7% of Sun-like stars could host habitable worlds. But the rate could be as high as 75%, scientists said.

NASA said it and other space agencies will continue to refine the estimate in future research, which will help shape plans for the next stages of exoplanet discoveries and telescopes. Currently, NASA's TESS mission is the latest planet-hunter seeking out exoplanets.

Huntsville/Redstone
Partly Cloudy
71° wxIcon
Hi: 73° Lo: 47°
Feels Like: 71°
Muscle Shoals
Partly Cloudy
74° wxIcon
Hi: 73° Lo: 43°
Feels Like: 74°
Huntsville/Madison
Partly Cloudy
72° wxIcon
Hi: 72° Lo: 43°
Feels Like: 72°
Decatur
Partly Cloudy
74° wxIcon
Hi: 74° Lo: 45°
Feels Like: 74°
Fort Payne
Partly Cloudy
71° wxIcon
Hi: 72° Lo: 44°
Feels Like: 71°
WAAY Radar
WAAY WAAY-TV Cam
WAAY Temperatures

Alabama Coronavirus Cases

Cases: 522512

Reported Deaths: 10790
CountyCasesDeaths
Jefferson755371494
Mobile39129799
Madison34124500
Tuscaloosa25408444
Montgomery24059573
Shelby23225242
Baldwin20730302
Lee15638166
Calhoun14358311
Morgan14171273
Etowah13705348
Marshall12012220
Houston10416279
Elmore10024203
Limestone9862148
Cullman9509191
St. Clair9486236
Lauderdale9280233
DeKalb8762183
Talladega8127173
Walker7151276
Autauga6763106
Jackson6762110
Blount6532133
Colbert6236132
Coffee5436113
Dale4781111
Russell431239
Franklin421382
Chilton4130110
Covington4069115
Tallapoosa3922148
Escambia390374
Dallas3528150
Chambers3519122
Clarke347360
Marion3076100
Pike306676
Lawrence296395
Winston273272
Bibb256761
Marengo248561
Geneva246475
Pickens233259
Barbour227155
Hale218675
Butler213268
Fayette209660
Henry188444
Cherokee182744
Randolph177841
Monroe173140
Washington165538
Macon156548
Clay150255
Crenshaw149557
Cleburne147041
Lamar140034
Lowndes137353
Wilcox124727
Bullock122040
Conecuh109728
Perry107726
Sumter103332
Coosa99428
Greene91434
Choctaw58824
Out of AL00
Unassigned00

Tennessee Coronavirus Cases

Cases: 835842

Reported Deaths: 12081
CountyCasesDeaths
Shelby930851587
Davidson88030924
Knox49813624
Hamilton43402485
Rutherford42319420
Williamson27545216
Sumner23492341
Montgomery19623224
Wilson18472229
Out of TN1803295
Unassigned16760132
Sullivan16184287
Blount15180194
Bradley14599147
Washington14177242
Maury13211169
Sevier13166175
Putnam11168173
Madison10789241
Robertson9607130
Anderson8627171
Hamblen8498171
Greene7739152
Tipton7226104
Coffee6831121
Dickson6734109
Cumberland6568127
Carter6468156
Bedford6426129
Gibson6402144
McMinn636597
Roane6191102
Jefferson6073121
Loudon601669
Lawrence580686
Hawkins5781106
Monroe570995
Warren551381
Dyer5361104
Franklin508688
Fayette492178
Obion450296
Cheatham444454
Cocke443798
Rhea431275
Lincoln430663
Marshall411158
Campbell409662
Weakley402862
Giles395399
Henderson372975
Macon358077
Carroll357582
White354868
Hardin349766
Hardeman346464
Lauderdale314444
Henry312475
Marion309946
Claiborne306273
Scott305545
Overton296961
Wayne294334
Hickman280546
McNairy276854
DeKalb275653
Smith274838
Haywood268361
Grainger259149
Trousdale249022
Morgan246039
Fentress238546
Johnson231638
Bledsoe209711
Chester209451
Crockett201048
Polk200024
Unicoi194549
Cannon188931
Union186034
Grundy177933
Humphreys174221
Lake169526
Sequatchie166728
Benton163240
Decatur157338
Lewis155826
Meigs134823
Stewart130828
Jackson129935
Clay109031
Houston108533
Perry105728
Moore100017
Van Buren83421
Pickett75624
Hancock54912

Community Events