Highlights From TESS's First Year ~ Credit: NASA GSFC/USRA
Music: "Elapsing Time" from Killer Tracks
NASA’s Transiting Exoplanet Survey Satellite (TESS) has discovered 21 planets outside our solar system and captured data on other interesting events occurring in the southern sky during its first year of science. TESS has now turned its attention to the Northern Hemisphere to complete the most comprehensive planet-hunting expedition ever undertaken.
TESS began hunting for exoplanets (or worlds orbiting distant stars) in the southern sky in July of 2018, while also collecting data on supernovae, black holes and other phenomena in its line of sight. Along with the planets TESS has discovered, the mission has identified over 850 candidate exoplanets that are waiting for confirmation by ground-based telescopes. ...
On July 18, the southern portion of the survey was completed and the spacecraft turned its cameras to the north. When it completes the northern section in 2020, TESS will have mapped over three quarters of the sky. ...
Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk. — Garrison Keillor
A young planet and a bright star offer glimpses into the past and future
Data on the brightness of a young star led to the discovery of exoplanet DS Tuc Ab.
Red arrows mark “transits” where the planet crossed between Earth and the planet’s
host star. The large, smooth variations are caused by the star, a result of its youth. Credit: Elisabeth Newton
Researchers at Dartmouth College have discovered a planet orbiting one of the brightest young stars known ... Aged at approximately 45 million years old, the star and its planet could provide valuable information on how planetary bodies form.
Known as an exoplanet because it is outside of the solar system, the planet was found as part of NASA’s Transiting Exoplanet Survey Satellite (TESS) mission. While thousands of exoplanet discoveries have already been made, only a handful have been discovered circling relatively young stars.
Planets can take millions or billions of years to reach maturity. Since that process cannot be observed in real time, researchers are searching for planets around young stars to catch the process in action and learn how planets form and evolve.The exoplanet observed in the Dartmouth research – known as DS Tuc Ab – can be considered a “pre-teen” in planetary time. The planet is no longer growing, but, because of its young age, it is still undergoing rapid changes like losing atmospheric gas as a result of the radiation coming from its host star. ...
DS Tuc Ab is about six times the size of Earth, between the sizes of Neptune and Saturn. Given the size, it likely has a composition similar to that of the giant planets in our solar system. The exoplanet has two suns and makes one full orbit around its main star in just eight days. ...
TESS Hunt for Young and Maturing Exoplanets (THYME):
A Planet in the 45 Myr Tucana–Horologium Association ~ Elisabeth R. Newton et al
Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk. — Garrison Keillor
NASA’s newest planet hunter, the Transiting Exoplanet Survey Satellite (TESS), has discovered three new worlds — one slightly larger than Earth and two of a type not found in our solar system — orbiting a nearby star. The planets straddle an observed gap in the sizes of known planets and promise to be among the most curious targets for future studies.
TESS Object of Interest (TOI) 270 is a faint, cool star more commonly identified by its catalog name: UCAC4 191-004642. The M-type dwarf star is about 40% smaller than the Sun in both size and mass, and it has a surface temperature about one-third cooler than the Sun’s. The planetary system lies about 73 light-years away in the southern constellation of Pictor. ...
The innermost planet, TOI 270 b, is likely a rocky world about 25% larger than Earth. It orbits the star every 3.4 days at a distance about 13 times closer than Mercury orbits the Sun. Based on statistical studies of known exoplanets of similar size, the science team estimates TOI 270 b has a mass around 1.9 times greater than Earth’s. ...
The other two planets, TOI 270 c and d, are, respectively, 2.4 and 2.1 times larger than Earth and orbit the star every 5.7 and 11.4 days. Although only about half its size, both may be similar to Neptune in our solar system, with compositions dominated by gases rather than rock, and they likely weigh around 7 and 5 times Earth’s mass, respectively. ...
Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk. — Garrison Keillor
TESS Helps Reveal Multiple Planets, Including Promising World Credit: NASA GSFC/USRA/UMCP
A piping hot planet discovered by NASA’s Transiting Exoplanet Survey Satellite (TESS) has pointed the way to additional worlds orbiting the same star, one of which is located in the star’s habitable zone. If made of rock, this planet may be around twice Earth’s size.
The new worlds orbit a star named GJ 357, an M-type dwarf about one-third the Sun’s mass and size and about 40% cooler that our star. The system is located 31 light-years away in the constellation Hydra. In February, TESS cameras caught the star dimming slightly every 3.9 days, revealing the presence of a transiting exoplanet — a world beyond our solar system — that passes across the face of its star during every orbit and briefly dims the star’s light. ...
The transits TESS observed belong to GJ 357 b, a planet about 22% larger than Earth. It orbits 11 times closer to its star than Mercury does our Sun. This gives it an equilibrium temperature — calculated without accounting for the additional warming effects of a possible atmosphere — of around 490 degrees Fahrenheit (254 degrees Celsius). ...
But while researchers were looking at ground-based data to confirm the existence of the hot Earth, they uncovered two additional worlds. The farthest-known planet, named GJ 357 d, is especially intriguing.
“GJ 357 d is located within the outer edge of its star’s habitable zone, where it receives about the same amount of stellar energy from its star as Mars does from the Sun,” said co-author Diana Kossakowski ... “If the planet has a dense atmosphere, which will take future studies to determine, it could trap enough heat to warm the planet and allow liquid water on its surface.”
Without an atmosphere, it has an equilibrium temperature of -64 F (-53 C), which would make the planet seem more glacial than habitable. The planet weighs at least 6.1 times Earth’s mass, and orbits the star every 55.7 days at a range about 20% of Earth’s distance from the Sun. The planet’s size and composition are unknown, but a rocky world with this mass would range from about one to two times Earth’s size. ...
GJ 357 c, the middle planet, has a mass at least 3.4 times Earth’s, orbits the star every 9.1 days at a distance a bit more than twice that of the transiting planet, and has an equilibrium temperature around 260 F (127 C). TESS did not observe transits from this planet, which suggests its orbit is slightly tilted — perhaps by less than 1 degree — relative to the hot Earth’s orbit, so it never passes across the star from our perspective. ...
Planetary system around the nearby M dwarf GJ 357 including a transiting,
hot, Earth-sized planet optimal for atmospheric characterization ~ R. Luque et al
Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk. — Garrison Keillor
TESS Catches Its First Star-Destroying Black Hole
When a star strays too close to a black hole, intense tides break it apart into a
stream of gas. The tail of the stream escapes the system, while the rest of it
swings back around, surrounding the black hole with a disk of debris. This video
includes images of a tidal disruption event called ASASSN-19bt taken by NASA’s
Transiting Exoplanet Survey Satellite (TESS) and Swift missions, as well as an
animation showing how the event unfolded. (Credit: NASA/GSFC/SVS/USRA)
For the first time, NASA’s planet-hunting Transiting Exoplanet Survey Satellite (TESS) watched a black hole tear apart a star in a cataclysmic phenomenon called a tidal disruption event. Follow-up observations by NASA’s Neil Gehrels Swift Observatory and other facilities have produced the most detailed look yet at the early moments of one of these star-destroying occurrences.
“TESS data let us see exactly when this destructive event, named ASASSN-19bt, started to get brighter, which we’ve never been able to do before,” said Thomas Holoien, a Carnegie Fellow at the Carnegie Observatories in Pasadena, California. “Because we identified the tidal disruption quickly with the ground-based All-Sky Automated Survey for Supernovae (ASAS-SN), we were able to trigger multiwavelength follow-up observations in the first few days. The early data will be incredibly helpful for modeling the physics of these outbursts.” ...
ASAS-SN, a worldwide network of 20 robotic telescopes headquartered at Ohio State University (OSU) in Columbus, discovered the event on Jan. 29. Holoien was working at the Las Campanas Observatory in Chile when he received the alert from the project’s South Africa instrument. Holoien quickly trained two Las Campanas telescopes on ASASSN-19bt and then requested follow-up observations by Swift, ESA’s (European Space Agency’s) XMM-Newton and ground-based 1-meter telescopes in the global Las Cumbres Observatory network.
TESS, however, didn’t need a call to action because it was already looking at the same area. The planet hunter monitors large swaths of the sky, called sectors, for 27 days at a time. This lengthy view allows TESS to observe transits, periodic dips in a star’s brightness that may indicate orbiting planets. ...
Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk. — Garrison Keillor
Dive Into TESS's Southern Sky Panorama Credit: NASA/GSFC/MIT/TESS, USRA, UMCP
Music: "Above Clouds" from Above and Below by Lars Leonhard
The glow of the Milky Way — our galaxy seen edgewise — arcs across a sea of stars in a new mosaic of the southern sky produced from a year of observations by NASA’s Transiting Exoplanet Survey Satellite (TESS). Constructed from 208 TESS images taken during the mission’s first year of science operations, completed on July 18, the southern panorama reveals both the beauty of the cosmic landscape and the reach of TESS’s cameras.
“Analysis of TESS data focuses on individual stars and planets one at a time, but I wanted to step back and highlight everything at once, really emphasizing the spectacular view TESS gives us of the entire sky,” said Ethan Kruse, a NASA Postdoctoral Program Fellow who assembled the mosaic at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
Within this scene, TESS has discovered 29 exoplanets, or worlds beyond our solar system, and more than 1,000 candidate planets astronomers are now investigating.
TESS divided the southern sky into 13 sectors and imaged each one of them for nearly a month using four cameras, which carry a total of 16 charge-coupled devices (CCDs). Remarkably, the TESS cameras capture a full sector of the sky every 30 minutes as part of its search for exoplanet transits. Transits occur when a planet passes in front of its host star from our perspective, briefly and regularly dimming its light. During the satellite’s first year of operations, each of its CCDs captured 15,347 30-minute science images. These images are just a part of more than 20 terabytes of southern sky data TESS has returned, comparable to streaming nearly 6,000 high-definition movies.
Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk. — Garrison Keillor
TESS Discovered Its 1st World Orbiting 2 Stars ~ Credit: NASA/GSFC/USRA
Music: "Albatross" from Universal Production Music
In 2019, when Wolf Cukier finished his junior year at Scarsdale High School in New York, he joined NASA’s Goddard Space Flight Center in Greenbelt, Maryland, as a summer intern. His job was to examine variations in star brightness captured by NASA’s Transiting Exoplanet Survey Satellite (TESS) and uploaded to the Planet Hunters TESS citizen science project.
“I was looking through the data for everything the volunteers had flagged as an eclipsing binary, a system where two stars circle around each other and from our view eclipse each other every orbit,” Cukier said. “About three days into my internship, I saw a signal from a system called TOI 1338. At first I thought it was a stellar eclipse, but the timing was wrong. It turned out to be a planet.”
TOI 1338 b, as it is now called, is TESS’s first circumbinary planet, a world orbiting two stars. The discovery was featured in a panel discussion on Monday, Jan. 6, at the 235th American Astronomical Society meeting in Honolulu. A paper, which Cukier co-authored along with scientists from Goddard, San Diego State University, the University of Chicago and other institutions, has been submitted to a scientific journal.
The TOI 1338 system lies 1,300 light-years away in the constellation Pictor. The two stars orbit each other every 15 days. One is about 10% more massive than our Sun, while the other is cooler, dimmer and only one-third the Sun’s mass.
TOI 1338 b is the only known planet in the system. It’s around 6.9 times larger than Earth, or between the sizes of Neptune and Saturn. The planet orbits in almost exactly the same plane as the stars, so it experiences regular stellar eclipses.
Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk. — Garrison Keillor
TESS Shows Ancient North Star Has Eclipses ~ Credit: NASA/GSFC/Chris Smith (USRA)
Astronomers using data from NASA’s Transiting Exoplanet Survey Satellite (TESS) have shown that Alpha Draconis, a well-studied star visible to the naked eye, and its fainter companion star regularly eclipse each other. While astronomers previously knew this was a binary system, the mutual eclipses came as a complete surprise.
“The first question that comes to mind is ‘how did we miss this?’” said Angela Kochoska, a postdoctoral researcher at Villanova University in Pennsylvania who presented the findings at the 235th meeting of the American Astronomical Society in Honolulu on Jan. 6. “The eclipses are brief, lasting only six hours, so ground-based observations can easily miss them. And because the star is so bright, it would have quickly saturated detectors on NASA’s Kepler observatory, which would also mask the eclipses.”
The system ranks among the brightest-known eclipsing binaries where the two stars are widely separated, or detached, and only interact gravitationally. Such systems are important because astronomers can measure the masses and sizes of both stars with unrivaled accuracy. ...
Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk. — Garrison Keillor
First Earth-size World in Habitable-zone ~ Credit: NASA/GSFC/Chris Smith (USRA)
Music credit: "Family Tree" from Universal Production Music
NASA’s Transiting Exoplanet Survey Satellite (TESS) has discovered its first Earth-size planet in its star’s habitable zone, the range of distances where conditions may be just right to allow the presence of liquid water on the surface. Scientists confirmed the find, called TOI 700 d, using NASA’s Spitzer Space Telescope and have modeled the planet’s potential environments to help inform future observations.
TOI 700 d is one of only a few Earth-size planets discovered in a star's habitable zone so far. Others include several planets in the TRAPPIST-1 system and other worlds discovered by NASA’s Kepler Space Telescope. ...
TOI 700 is a small, cool M dwarf star located just over 100 light-years away in the southern constellation Dorado. It’s roughly 40% of the Sun’s mass and size and about half its surface temperature. The star appears in 11 of the 13 sectors TESS observed during the mission’s first year, and scientists caught multiple transits by its three planets. ...
Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk. — Garrison Keillor
finally! Will this system be a target for direct observations from any of our newest instruments?
Aliens will find Earth absolutely amazingly beautiful and fragile to behold. But if they get close enough, they'll see 7,000,000,000 of us and think "Uh oh, that's a lot for such a small planet. Wonder if we should help?"
<<The Smell-O-Scope allows the user to smell odours over astronomically long distances ("If a dog craps anywhere in the universe, you can bet I won't be out of the loop"). It was created by Professor Farnsworth in 2999 and won the Academy of Inventors Academy Prize in 3000 after the prize had been taken away from Dr. Ogden Wernstrom as it became apparent that he was a jackass. The degree of odour can be measured on a meter called the "Funkometer". It is unknown how the device functions, but it apparently has a lens and a stench coil. As Cubert points out, it is impossible for odour molecules to travel through the vacuum of space and reach the user's nose. However, it is possible that the Smell-O-Scope actually analyzes various spectrums, determines the chemical makeup, and reproduces the smell within its nostril-tubes, much like a television reproduces sounds and images.>>
On July 4, NASA’s Transiting Exoplanet Survey Satellite (TESS) finished its primary mission, imaging about 75% of the starry sky as part of a two-year-long survey. In capturing this giant mosaic, TESS has found 66 new exoplanets, or worlds beyond our solar system, as well as nearly 2,100 candidates astronomers are working to confirm.
“TESS is producing a torrent of high-quality observations providing valuable data across a wide range of science topics,” said Patricia Boyd ... “As it enters its extended mission, TESS is already a roaring success.”
TESS monitors 24-by-96-degree strips of the sky called sectors for about a month using its four cameras. The mission spent its first year observing 13 sectors comprising the southern sky and then spent another year imaging the northern sky.
Now in its extended mission, TESS has turned around to resume surveying the south. In addition, the TESS team has introduced improvements to the way the satellite collects and processes data. Its cameras now capture a full image every 10 minutes, three times faster than during the primary mission. A new fast mode allows the brightness of thousands of stars to be measured every 20 seconds, along with the previous method of collecting these observations from tens of thousands of stars every two minutes. The faster measurements will allow TESS to better resolve brightness changes caused by stellar oscillations and to capture explosive flares from active stars in greater detail.
These changes will remain in place for the duration of the extended mission, which will be completed in September 2022. After spending a year imaging the southern sky, TESS will take another 15 months to collect additional observations in the north and to survey areas along the ecliptic – the plane of Earth’s orbit around the Sun – that the satellite has not yet imaged. ...
Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk. — Garrison Keillor
Familiar stars shine, nebulae glow, and nearby galaxies tantalize in a new panorama of the northern sky assembled from 208 pictures captured by NASA’s Transiting Exoplanet Survey Satellite (TESS). The planet hunter imaged about 75% of the sky in a two-year-long survey and is still going strong.
TESS has discovered 74 exoplanets, or worlds beyond our solar system. Astronomers are sifting through some 1,200 additional exoplanet candidates, where potential new worlds await confirmation. More than 600 of these candidates lie in the northern sky.
TESS locates planets by simultaneously monitoring many stars over large regions of the sky and watching for tiny changes in their brightness. When a planet passes in front of its host star from our perspective, it blocks some of the star’s light, causing it to temporarily dim. This event is called a transit, and it repeats with every orbit of the planet around the star. This technique has proven to be the most successful planet-finding strategy so far, accounting for about three quarters of the nearly 4,300 exoplanets now known. The data collected also allow for the study of other phenomena such as stellar variations and supernova explosions in unprecedented detail.
The northern mosaic covers less of the sky than its southern counterpart, which was imaged during the mission’s first year of operations. For about half of the northern sectors, the team decided to angle the cameras further north to minimize the impact of scattered light from Earth and the Moon. This results in a prominent gap in coverage. ...
Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk. — Garrison Keillor
