Found 21 light years from Earth
A new "secret" planetary system that includes three super-Earths and one outer giant planet has been discovered by astronomers at a distance of just 21 light years from Earth.
The remarkable system, named HD219134, in the constellation Cassiopeia hosts one outer giant planet and three inner super-Earths, one of which transits in front of the star.
The transiting super-Earth has a density similar to the Earth's. It is by far the closest transiting planet known today, researchers said.
The system is so close that astronomers already dream about taking pictures of the new "Stars."
HARPS-N, designed and built by an international consortium and installed at the Telescopio Nazionale Galileo on the La Palma island in Spain, unveiled the exceptional planetary system around HD219134.
The star, a 5th magnitude K dwarf, slightly colder and less massive than our Sun, is so bright that we can follow it with a naked eye from dark skies, next to one leg of the W-shape Cassiopeia constellation, all year round in our boreal hemisphere, researchers said.
The cortege of planets is composed of three mostly rocky super-Earths and an outer giant planet, a configuration reminiscent of our own Solar System, they said.
"When the first HARPS-N radial-velocity measurements indicated the presence of a 3-day planet around HD219134, we immediately asked NASA for Spitzer space telescope time," said Ati Motalebi, astronomer at University of Geneva (UNIGE) and first author of the paper describing the discovery.
"The idea was to check for a potential transit of the planet in front of the star, a mini eclipse, that would allow us to measure the size of the planet," she said.
HD219134b does indeed transit the star. It is by far the closest transiting planet known, and likely to remain one of the closest ever.
The mass of the planet obtained from the ground-based radial velocities, combined with the planet radius derived from space observations with Spitzer, yield the mean density of the planet.
HD219134b is 4.5 times more massive than the Earth and 1.6 times larger, what planet hunters call a super-Earth. Its mean density is close to the density of the Earth, suggesting a possibly similar composition as well.
The team discovered three additional longer-period planets in the system from the HARPS-N radial velocities.
In the inner regions, a planet weighing 2.7 times the Earth orbits HD219134 in 6.8 days, and a planet of 8.7 times the mass of the Earth resides on a 46.8-day orbit.
If, by chance, these 2 planets would be in a coplanar configuration with their 3rd inner sister, as often observed for compact systems, the whole family might be transiting.
The research will be published in the Astronomy & Astrophysics journal.
User Comments:
- First T-20 match without shakib and tamim india loss
- At the age of 85, goodbye to cricket
- Shakib Ranking position change
- Bangladesh ended the first day of the unbeaten century
- Saif Hassan disappointed the chosen in the first roles
- Proteas defeats the Lankan in 2nd ODI
- IDB expresses concern over changes in Islami Bank
- 20 potential ECS names nominated
- Could not believe that Sunny Leone wanted him in 'Laila Main Laila' Shah Rukh Khan
- India beat England in the 1st T20 match
- Look your best on Valentine's Day
- Priyanka said that India will always be identified
- Global banking rules agreement 'once the dust settles in the United States
- May trumpet as host of the first foreign leader
- Do not interfere in the Bangladesh case, Qadir says foreign
- Turkey's ambassador to Dhaka
- 'Ice Age: New trailer collision: the threat of global asteroids
- Bale hits real winner
- Woman found dead in a city hotel
- Withdrawal of unemployed nurses strike
- Tangail filed on Hindu murder case
- Foreign Minister meets King Abdullah Foundation trip in Saudi Arabia, Prince Turkey
- Hasina praised Bangladesh bowling sensation Mustafizur
- Rains in Sylhet, the heat wave plays extra time in the rest of Bangladesh
- BNP chief Khaleda sees more danger than ever before in Bangladesh
- I do not want it, I want to win: Dunga
- Asks the Bangladesh government to take a strong position against killer:Denmark
- My mom is not here to meet Neetu Kapoor, Katrina Kaif clear
- ICC World T20: England Qualify For Final
- Tonu murder sad every part of the army, says ISPR
- ADB Bangladesh sees FY GDP growing at 6.7% in 2015-16
- Court orders arrest of Khaleda's deadly bus firebombing in Dhaka
- Standard Chartered cards stop working due to a down server
- Corruption can progress obstruction of a country: President
- The uncertainty of the cloud cleared, Hero 420, released Friday
- To suggest pollution to protect your skin
- Trouble in Parliament to answer questions on the delay Interior Minister
- Hasina urges teachers to promote sports
- 5D can record human history!
- I'm still a child, says Kareena
- Saudi, Russia agreed oil production freeze
- Twenty20 World Cup announced
- The death of former chief Boutros-ghali UN
- Arrest warrant issued against Daily Star editor
- Per capita income of Bangladesh 2014-15, increasing to $ 1.316 in fiscal year
- Khaleda Zia subcommittees for BNP
- BSMMU Abdul Hannan appointed new Register
- Citizens can update fingerprints for the ceremony at the office
- Executes N Korea army chief
- Twenty20 Women World Cup team announced
- Star Journo concern over the threat to the leader, its editor
- US 'Intel warning of the details of the terrorist group in Bangladesh
- To be tried Padma bridge 'conspirators': Prime Minister
- Road crashes: High Court order on all hospital emergency service
- muslin and fund research: analyst
- Chief Justice appeal eats division into three judges
- Keraniganj prime murder suspect killed in shootout school Abdullah: RAB
- Bangladesh lost a High Court for staff accommodation
- ICT sentence Taher, Noni Netrokona death
- Ghazipur knife 2 DB
- French minister at the UN sends carbon pricing
- '' Now it Rabby no bar
- Khulna JCD President Kamran held
- Police want Bank Medical College
- Fakhrul went to Singapore for treatment
- Apple warns iPhone sales to fall
- Kristen Stewart speaks up on gender inequality
- China to increase JVs in Bangladesh
- Konta 33-year British drought to break beats Zhang
- India waives visa fees Bangladesh
- Patient's death: 2 CTG doctors get bail
- Specialised police to combat terrorism: PM
- The school forced students to buy additional books
- Romance to change you as a person does
- AL betrayed the spirit of liberation war: khalida
- World Cup 2015: Dhoni's men will be wary of Bangladesh
- An eve teasing incident scarred my life
- Man allegedly kill wife
- 44 years later widows receive justice: sajib wazed joy
- Employee bonuses decline at Cognizant
- Happy loses Lawyer
- Shamsul Hoque Khan School top....... in Dhaka broad
- BNP leader Nasir Uddin Ahmed Pinto dies
- Proteas defeats the Lankan in 2nd ODI
- Dr. Yunus...................Three Zero Theory
- Turkey's ambassador to Dhaka
- 20 potential ECS names nominated
- Mashrafe-Rubel broke the English lineup
- Think different! Try sex in storeroom
- Khaleda Zia subcommittees for BNP
- IDB expresses concern over changes in Islami Bank
- High Court says : Why not second time in DU
- Woman found dead in a city hotel
- Kim Kardashian to strip nude again
- Tangail filed on Hindu murder case
- Refused bail petition of ..... Ruhul Kabir Rizvi
- Could not believe that Sunny Leone wanted him in 'Laila Main Laila' Shah Rukh Khan
- Romance to change you as a person does
- Finance Minister AMA Muhith to place budget for seventh time... Budget
- Look your best on Valentine's Day