Posts Tagged ‘exoplanet’

Water Worlds are Everywhere

August 18, 2018

Scientists have shown that water is likely to be a major component of those exoplanets (planets orbiting other stars) which are between two to four times the size of Earth. It will have implications for the search of life in our Galaxy. The work is presented at the Goldschmidt Conference in Boston.

Now a new evaluation of data from the exoplanet-hunting Kepler Space Telescope and the Gaia mission indicates that many of the known planets may contain as much as 50% water. This is much more than the Earth’s 0.02% (by weight) water content.

“It was a huge surprise to realize that there must be so many water-worlds”, said lead researcher Dr. Li Zeng (Harvard University),

Scientists have found that many of the 4000 confirmed or candidate exoplanets discovered so far fall into two size categories: those with the planetary radius averaging around 1.5 that of the Earth, and those averaging around 2.5 times the radius of the Earth.
Read more at: https://phys.org/news/2018-08-water-worlds-common-exoplanets-vast-amounts.html#jCp

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Exoplanets in the news

June 29, 2018

There are currently about fifty known exoplanets whose diameters range from Mars-sized to several times the Earth’s and which also reside within their stars’ habitable zone – the orbital distance within which their surface temperatures permit liquid water. These exoplanets are currently our best candidates for hosting life.

Read more at: https://phys.org/news/2018-06-habitable-world-exoplanets.html#jCp

A new study from the Georgia Institute of Technology provides new clues indicating that an exoplanet 500 light-years away is much like Earth.

Kepler-186f is the first identified Earth-sized planet outside the solar system orbiting a star in the . This means it’s the proper distance from its for liquid water to pool on the surface.

The Georgia Tech study used simulations to analyze and identify the exoplanet’s spin axis dynamics. Those dynamics determine how much a planet tilts on its axis and how that tilt angle evolves over time. Axial tilt contributes to seasons and climate because it affects how sunlight strikes the planet’s surface.

The researchers suggest that Kepler-186f’s is very stable, much like the Earth, making it likely that it has regular seasons and a stable climate. The Georgia Tech team thinks the same is true for Kepler-62f, a super-Earth-sized planet orbiting around a star about 1,200 light-years away from us.

Read more at: https://phys.org/news/2018-06-clues-earth-like-exoplanets.html#jCp

Kepler Completes Campaign 17

May 15, 2018

kep18active

  • Campaign 17 completed successfully
  • Campaign 18 underway
  • Apophis asteroid in view
  • Campaign 16 data processing complete

 

Planets possibly discovered outside of our Galaxy

February 4, 2018

Until this study, there has been no evidence of planets in other galaxies.  This is the first time anyone has discovered planets outside our galaxy.

ouastrophysi

A University of Oklahoma astrophysics team has discovered for the first time a population of planets beyond the Milky Way galaxy. Using microlensing—an astronomical phenomenon and the only known method capable of discovering planets at truly great distances from the Earth among other detection techniques—OU researchers were able to detect objects in extragalactic galaxies that range from the mass of the Moon to the mass of Jupiter.  This galaxy is located 3.8 billion light years away.

Read more at: https://phys.org/news/2018-02-astrophysicists-planets-extragalactic-galaxies-microlensing.html#jCp

Kepler Exo Planet Count

December 30, 2017

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related:

https://gregdougall.wordpress.com/2017/06/02/drake-equation-revisited/

Tell me what you think!  Leave a comment below…or share post with others

Shot of ESPRESSO seeking life

December 7, 2017

5-firstlightfoThe Echelle SPectrograph for Rocky Exoplanet and Stable Spectroscopic Observations (ESPRESSO) has successfully made its first observations. Installed on ESO’s Very Large Telescope (VLT) in Chile, ESPRESSO will search for exoplanets with unprecedented precision by looking at the minuscule changes in the light of their host stars. For the first time ever, an instrument will be able to sum up the light from all four VLT telescopes and achieve the light collecting power of a 16-meter telescope.

ESPRESSO has achieved first light on ESO’s Very Large Telescope at the Paranal Observatory in northern Chile. This new, third-generation echelle spectrograph is the successor to ESO’s hugely successful HARPS at the La Silla Observatory. HARPS can attain a precision of around one metre per second in velocity measurements, whereas ESPRESSO aims to achieve a precision of just a few centimetres per second, due to advances in technology and its placement on a much bigger telescope.

The lead scientist for ESPRESSO, Francesco Pepe from the University of Geneva in Switzerland, explains its significance: “This success is the result of the work of many people over 10 years. ESPRESSO isn’t just the evolution of our previous instruments like HARPS, but it will be transformational, with its higher resolution and higher precision. And unlike earlier instruments it can exploit the VLT’s full collecting power—it can be used with all four of the VLT Unit Telescopes at the same time to simulate a 16-metre . ESPRESSO will be unsurpassed for at least a decade—now I am just impatient to find our first rocky planet!”

Read more at: https://phys.org/news/2017-12-espressothe-planet-hunter.html#jCp

Updated: Drake Equation Revisited

June 2, 2017

1 in 22,286 solar systems in the Milky Way host some form of life, such as plant, animal, human, etc.

1 in 42,507 solar systems in the Milky Way host human life.

1 in 59,316 solar systems in the Milky Way host advanced human life.

 

1 in 61,571 solid planets or moons in the Milky Way host some form of life, such as plant, animal, human, etc.

1 in 117,439 solid planets or moons in the Milky Way host human life.

1 in 163,878 solid planets or moons in the Milky Way host advanced human life.


N = 2,630,000 = the number of civilizations in our galaxy where communication may be possible


 

1 in 7.43 solar systems/stars in the Milky Way have suns/stars similar to our own sun, SOL.

An estimated 6 trillion to 7 trillion human civilizations exist in our DERN Universe and in our space time configuration.

The estimated number of human civilizations that exist throughout all of Creation, is “in the vigintillions”, a number with 63 zeroes after it.


Total number of Identified Exoplanets: 3,499

Kepler Exoplanet Count: 2,491

Kepler:

Candidates: 4,034
Confirmed: 2,335
Small Habitable Zone Confirmed: 30

K2:

Candidates: 520
Confirmed: 156

(as of July 20, 2017)

First Atmosphere detected around Earth sized exoplanet

April 7, 2017

April 6, 2017

Astronomers have detected an atmosphere around the super-Earth GJ 1132b. This marks the first detection of an atmosphere around a low-mass super-Earth, in terms of radius and mass the most Earth-like planet around which an atmosphere has yet been detected. Thus, this is a significant step on the path towards the detection of life on an exoplanet. The team, which includes researchers from the Max Planck Institute for Astronomy, used the 2.2-m ESO/MPG telescope in Chile to take images of the planet’s host star, GJ 1132, and measured the slight decrease in brightness as the planet and its atmosphere absorbed some of the starlight while passing directly in front of their host star.

While it’s not the detection of life on another planet, it’s an important step in the right direction: the detection of an atmosphere around the super-Earth GJ 1132b marks the first time an atmosphere has been detected around a planet with a mass and radius close to Earth’s mass and radius (1.6 Earth masses, 1.4 Earth radii).

Astronomers’ current strategy for finding life on another planet is to detect the chemical composition of that planet’s atmosphere, on the lookout for certain chemical imbalances that require the presence of living organisms as an explanation. In the case of our own Earth, the presence of large amounts of oxygen is such a trace.

We’re still a long way from that detection though. Until the work described in this article, the (few!) observations of light from exoplanet atmospheres all involved planets much more massive than Earth: gas giants—relatives of our own solar system’s Jupiter—and a large super-Earth with more than eight times the Earth’s mass. With the present observation, we’ve taken the first tentative steps into analyzing the atmosphere of smaller, lower-mass planets that are much more Earth-like in size and mass.

The planet in question, GJ 1132b, orbits the red dwarf star GJ 1132 in the southern constellation Vela, at a distance of 39 light-years from us. Recently, the system has come under scrutiny by a team led by John Southworth (Keele University, UK). The project was conceived, and the observations coordinated, by Luigi Mancini, formerly of the Max Planck Institute for Astronomy (MPIA) and now working at the University of Rome Tor Vergata. Additional MPIA team members were Paul Mollière and Thomas Henning.

The team used the GROND imager at the 2.2-m ESO/MPG telescope of the European Southern Observatory in Chile to observe the planet simultaneously in seven different wavelength bands. GJ 1132b is a transiting planet: From the perspective of an observer on Earth, it passes directly in front of its star every 1.6 days, blocking some of the star’s light.

The size of stars like GJ 1132 is well known from stellar models. From the fraction of starlight blocked by the planet, astronomers can deduce the planet’s size—in this case around 1.4 times the size of the Earth. Crucially, the new observations showed the planet to be larger at one of the infrared wavelengths than at the others. This suggests the presence of an atmosphere that is opaque to this specific infrared light (making the planet appear larger) but transparent at all the others. Different possible versions of the atmosphere were then simulated by team members at the University of Cambridge and the Max Planck Institute for Astronomy. According to those models, an atmosphere rich in water and methane would explain the observations very well.

The discovery comes with the usual exoplanet caveats: while somewhat larger than Earth, and with 1.6 times Earth’s mass (as determined by earlier measurements), observations to date do not provide sufficient data to decide how similar or dissimilar GJ 1132b is to Earth. Possibilities include a “water world” with an atmosphere of hot steam.

The presence of the atmosphere is a reason for cautious optimism. M dwarfs are the most common types of star, and show high levels of activity; for some set-ups, this activity (in the shape of flares and particle streams) can be expected to blow away nearby planets’ atmospheres. GJ 1132b provides a hopeful counterexample of an atmosphere that has endured for billion of years (that is, long enough for us to detect it). Given the great number of M dwarf stars, such atmospheres could mean that the preconditions for life are quite common in the universe.

In any case, the new observations make GJ 1132b a high-priority target for further study by instruments such as the Hubble Space Telescope, ESO’s Very Large Telescope, and the James Webb Space Telescope slated for launch in 2018.

The work described here has been published as J. Southworth et al., “Detection of the atmosphere of the 1.6 Earth mass exoplanet GJ 1132B” in the Astronomical Journal.

 

Visible Light Spectrum from Alien Planet Measured for 1st Time

April 22, 2015

Astronomers have detected an exoplanet’s visible-light spectrum directly for the first time ever, a milestone that could help bring many other alien worlds into clearer focus down the road.

Wide-field view of the sky around the star 51 Pegasi

Image showing the sky around the star 51 Pegasi in the northern constellation of Pegasus. This image was created from photographic material forming part of the Digitized Sky Survey 2. Credit: ESO/Digitized Sky Survey 2
(editor’s note: I believe the planet is to the left of the star in the center)

The scientists used the HARPS instrument on the European Southern Observatory’s 3.6-meter telescope at the La Silla Observatory in Chile to study the spectrum of visible light reflected off the exoplanet 51 Pegasi b, which lies about 50 light-years from Earth in the constellation Pegasus.

51 Pegasi b, a “hot Jupiter” gas giant that orbits close to its parent star, was spotted in 1995, when it became the first alien world ever discovered around a sunlike star. (The first exoplanets of any type were found in 1992 around a superdense, rotating stellar corpse called a pulsar.)

Researchers most often study exoplanet atmospheres by analyzing the starlight that passes through them when worlds cross their stars’ faces from Earth’s perspective. This method, known as transit spectroscopy, is restricted to use on systems in which the stars and planets align.

 

The new strategy used with 51 Pegasi b, on the other hand, does not depend on planetary transits and could thus find broader applicability, researchers said.

The technique offers other scientific advantages as well.

“This type of detection technique is of great scientific importance, as it allows us to measure the planet’s real mass and orbital inclination, which is essential to more fully understand the system,” study lead author Jorge Martins, of the Instituto de Astrofísica e Ciências do Espaço (IA) and the Universidade do Porto in Portugal, said in a statement.

“It also allows us to estimate the planet’s reflectivity, or albedo, which can be used to infer the composition of both the planet’s surface and atmosphere,” Martins added.

The new data suggest that 51 Pegasi b is highly reflective, a bit larger in diameter than Jupiter and about half as massive as our solar system’s biggest planet, researchers said.

The new observations by HARPS (which is short for High Accuracy Radial velocity Planet Searcher) provide a vital proof of concept for the new technique, which could really come into its own when employed with instruments on bigger telescopes, such as the European Southern Observatory’s Very Large Telescope (VLT), researchers said.

“We are now eagerly awaiting first light of the ESPRESSO spectrograph on the VLT so that we can do more detailed studies of this and other planetary systems,” said co-author Nuno Santos, also of the IA and Universidade do Porto.

The new study was published today (April 22) in the journal Astronomy & Astrophysics.

How to Find Vega, a Scintillating Star in a Cosmic Harp

September 5, 2014

How to Find Vega, a Scintillating Star in a Cosmic Harp.

Shining almost directly overhead as darkness falls these days is the brilliant bluish-white star Vega, in the constellation of Lyra, the Harp. 

Vega is the fifth-brightest star in the night sky, and the third-brightest visible from midnorthern latitudes, trailing just Sirius and Arcturus. Also, as seen from midnorthern latitudes such as New York or Madrid, Vega goes below the horizon for only about seven hours a day, meaning you can see it on any night of the year. 

As viewed from farther south, Vega — the brightest of the three stars forming the large “Summer Triangle” consisting of Vega, Altair and Deneb — lies below the horizon for a longer interval of time. Conversely, for Alaska, central and northern Canada and central and northern Europe, Vega never sets and is readily visible on any night of the year.

more at… http://www.space.com/27033-vega-star-harp-constellation-lyra.html

670px-Find-Your-Way-Around-the-Summer-Night-Sky-Step-2

 vega-lyra_sky-map