TESS Discovers Its Third Small Exoplanet: Sub-Neptune HD 21749b | Astronomy

NASA
K2-288Bb

Since Kepler has shut its operations, NASA is hoping that a new space telescope - Transiting Exoplanet Survey Satellite (TESS), will take charge of the proceedings.

The new planet, named HD 21749b, orbits a bright, nearby dwarf star about 53 light-years away, in the constellation Reticulum, and appears to have the longest orbital period of the three planets so far identified by TESS.

Pi Mensae c is the second planet found orbiting its star, and has a period of six days.

"It's a very exciting discovery due to how it was found, its temperate orbit, and because planets of this size seem to be relatively uncommon", according to University of Chicago grad student Adina Feinstein, lead author of a paper describing the orb, published by The Astronomical Journal.

"It's the coolest small planet that we know of around a star this bright", Dr Dragomir said.

Its size, three times that of Earth, makes it a sub-Neptune.




An exoplanet three times the size of Earth, but 23 times heavier, has been discovered relatively close to our solar system. HD 21749b is more likely to be made of gas rather than being a rocky planet. "If confirmed, it will be the smallest planet we have found to date", study co-author Chelsea Huang, a colleague of Dragomir's at the MIT Kavli Institute, said today during a briefing at the American Astronomical Society's winter meeting in Seattle. This means that on its surface could be liquid water. Scientists have also discovered evidence for another planet in the same planetary system without any official confirmation. However, observations of a third transit were needed to confirm the discovery of an exoplanet. So far, it's right on schedule: About a quarter of the sky has been photographed, eight months after its launch and six months after it began its two-year primary science mission. The primary aim is to look for exoplanet transits, which occur when a planet passes in front of its host star as viewed from TESS's perspective.

"It's the coolest small planet that we know of around a star this bright", Dragomir said.

In addition to HD 21749b, TESS has picked up on six supernovae, which represent one of the final, cataclysmic stages of a star's lifespan.

TESS does this work by carving the sky up into overlapping sectors, studying each one for 27 days at a time. "NASA's Kepler space telescope caught five of these events as they brightened during its first four years of operations". Their proximity to Earth will enable detailed characterization of the planets through follow-up observations from space- and ground-based telescopes. They determined that they should be able to find the signal again, in TESS's "sector 3" data - which they succeeded in doing. Because TESS is programmed to look at a portion of the sky for only 27 days, any planets with a longer orbit are hard to identify.

NASA expects TESS to allow for the cataloging of more than 1,500 exoplanets, but it has the potential to find thousands.

Related news:

Hot News

isis-killer-beheading-video-story-top Outrage over apparent 'segregation' in South Africa school
Jan 11, 2019 - 16:27
I was told from the beginning that the school offers Afrikaans as a medium of instruction and didn't have problems with that. The North West Education Department has called on parents and the broader community to allow it to finish its investigation.

isis-killer-beheading-video-story-top Former Miami Dolphins coach Adam Gase takes over at New York Jets
Jan 11, 2019 - 15:30
Gase worked with Manning from 2012 through 2014-first as the Broncos' quarterbacks coach, and then as offensive coordinator. But Tannehill missed the entire 2017 season, and though he was reasonably efficient when he did play, it wasn't the same.

isis-killer-beheading-video-story-top Brexit: May suffers second defeat on Brexit amendment
Jan 11, 2019 - 14:56
Mr Hunt's words were seen as a way to win over hardline Brexiteers who are not convinced by Mrs May's deal. It could also open the door to alternatives, such as a referendum.

isis-killer-beheading-video-story-top Maurizio Sarri discusses Bayern target, delivers positive update for Chelsea fans
Jan 11, 2019 - 13:04
He has insisted he will not sign a new contract and wants to play in the Bundesliga. Sarri gave the winger a start amid transfer talk linking him with Bayern Munich .

isis-killer-beheading-video-story-top Russian attorney Natalia Veselnitskaya charged with obstruction of justice in United States court
Jan 11, 2019 - 12:41
A lawyer at BakerHostetler, which represented Prevezon at the time of the November 2015 filing, declined to comment. The first email in a chain released by Donald Trump Jr. also references a Russian prosecutor.

isis-killer-beheading-video-story-top Rami Malek explains that cringe Nicole Kidman snub
Jan 10, 2019 - 23:48
The news comes on the heels of a big night for Bohemian Rhapsody's cast and crew last Sunday at the Golden Globes. In the other TV categories, The Americans was named best drama and The Kominsky Method picked up best TV comedy.

isis-killer-beheading-video-story-top Mueller Believes Manafort Shared 2016 Polling Data With Alleged Russian Intel Agent
Jan 10, 2019 - 23:44
Kilimnik on more than one occasion", his attorneys quote the special counsel as saying, and "'acknowledged' that he and Mr. Kilimnik is a veteran of the Russian army whom Mueller accused of having ties to Russian intelligence agencies.

isis-killer-beheading-video-story-top Pompeo starts Middle East visit to ramp up pressure on Iran
Jan 10, 2019 - 23:32
A police band serenaded Prime Minister Adel Abdul Mahdi, who presided over the celebration before meeting Pompeo in private. Turkey's rock-ribbed position is nearly utterly antithetical to anything the Israelis might want to hear.

isis-killer-beheading-video-story-top Duchess of Sussex Meghan Markle to become new National Theatre Royal Patron
Jan 10, 2019 - 23:28
Meghan , who Wednesday Prince Harry in May, will now assume her role as the royal patron of several charitable organisations. Buckingham Palace said that "patronages generally reflect the interests of the member of the Royal Family involved".

isis-killer-beheading-video-story-top Maine CDC confirms 3 deaths from flu in state this season
Jan 10, 2019 - 23:10
Regular hand washing, getting the flu shot, and sneezing into your arm rather than your hand are important preventive measures. Viruses are passed by contact between people, so remember these simple tips for staying healthy and keeping others healthy: 1.

isis-killer-beheading-video-story-top Pound at one-week high as Brexit vote nears
Jan 09, 2019 - 14:01
Boris Johnson, who helped lead the Brexit campaign, said that voters would not be scared into backing a poor deal. Brexit minister Stephen Barclay dismissed the possibility and said that he had not spoken to the EU.

isis-killer-beheading-video-story-top Chargers QB Philip Rivers says L.A. ‘doesn’t care’ about Patriots’ dynasty
Jan 09, 2019 - 13:18
It's been very educational for me every time I've gone through it and I've appreciated every single one of them. It was the only quarter of Wilson's career, including playoffs, in which he had negative yards passing.

isis-killer-beheading-video-story-top China names new moon rover "Yutu-2"
Jan 09, 2019 - 12:06
Beijing is planning to send another lunar lander, Chang'e 5, next year to collect samples and bring them back to Earth. A lunar rover has begun exploring the far side of the moon in the first-ever mission of its kind.

isis-killer-beheading-video-story-top China lodges 'stern' protest over USA warship sailing through South China Sea
Jan 09, 2019 - 11:55
Official U.S. fuel storage data from the Energy Information Administration (EIA) is due at 1800 GMT on Wednesday. President Donald Trump said the state of the country's economy is giving China an incentive to negotiate.

isis-killer-beheading-video-story-top Lok Sabha okays plan to tweak citizenship law
Jan 09, 2019 - 11:36
The AGP had earlier expressed reservations with the Bill saying it would make the Assam Accord meaningless. BJP allies Shiv Sena and JD-U have announced that they would oppose the bill in Parliament.