ESPRESSO - AbsoluteAstronomy.com

ESPRESSO is a new-generation, high-resolution, fiber-fed and cross-dispersed echelle spectrograph (R = 140,000) for the visible wavelength range (350 nm – 720 nm), for the European Southern Observatory

European Southern Observatory

The European Southern Observatory is an intergovernmental research organisation for astronomy, supported by fifteen countries...

's Very Large Telescope

Very Large Telescope

The Very Large Telescope is a telescope operated by the European Southern Observatory on Cerro Paranal in the Atacama Desert of northern Chile. The VLT consists of four individual telescopes, each with a primary mirror 8.2m across, which are generally used separately but can be used together to...

. Its main feature is the spectroscopic stability and the radial velocity

Radial velocity

Radial velocity is the velocity of an object in the direction of the line of sight . In astronomy, radial velocity most commonly refers to the spectroscopic radial velocity...

precision. With incredible spectroscopic precision, it will be able to detect Earth-like planet

Earth-like planet

Earth-like planet is used as a synonym for either of the following:* Earth analog, denoting planets of a higher degree of similarity to Earth than terrestrial planets...

s. For example, our Earth induces a radial-velocity variation of 9 cm/s

Second

The second is a unit of measurement of time, and is the International System of Units base unit of time. It may be measured using a clock....

on our Sun.

The requirement is to reach 10 cm/s

Second

The second is a unit of measurement of time, and is the International System of Units base unit of time. It may be measured using a clock....

, but the aimed goal is to obtain a precision level of a few cm/s

Second

The second is a unit of measurement of time, and is the International System of Units base unit of time. It may be measured using a clock....

. Installation and commissioning of ESPRESSO at the VLT is foreseen in 2016.

The instrument is capable of operating in 1-UT mode and in 4-UT mode. In 4-UT mode, in which all the four 8-m telescopes are connected incoherently to form a 16-m equivalent telescope the spectrograph will reach extremely faint objects.

Sensitivity

For example (for G2V type stars):

Rocky Planets around stars as faint as V ~ 9 in (in 1 UT mode)
Neptune mass planets around stars as faint as V ~ 12 (in 4 UT mode )
Earth-like planets around stars as faint as V ~ 9 (CODEX
Codex
A codex is a book in the format used for modern books, with multiple quires or gatherings typically bound together and given a cover.Developed by the Romans from wooden writing tablets, its gradual replacement...

on the E-ELT ) (2025)

Comparison between ESPRESSO and CODEX


	ESPRESSO	CODEX Codex A codex is a book in the format used for modern books, with multiple quires or gatherings typically bound together and given a cover.Developed by the Romans from wooden writing tablets, its gradual replacement...
Telescope Telescope A telescope is an instrument that aids in the observation of remote objects by collecting electromagnetic radiation . The first known practical telescopes were invented in the Netherlands at the beginning of the 1600s , using glass lenses...	VLT VLT VLT may stand for:* Very Large Telescope, a system of four large optical telescopes organized in an array formation, located in northern Chile... (8m)	E-ELT (42m)
Scope	Rocky Planets	Earth-Like
Sky Aperture Aperture In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture of an optical system is the opening that determines the cone angle of a bundle of rays that come to a focus in the image plane. The aperture determines how collimated the admitted rays are,...	1 arcsec	0.80 arcsec
R	150000	150000
λ Lambda Lambda is the 11th letter of the Greek alphabet. In the system of Greek numerals lambda has a value of 30. Lambda is related to the Phoenician letter Lamed . Letters in other alphabets that stemmed from lambda include the Roman L and the Cyrillic letter El... Coverage	350-730 nm	380-680 nm
λ Lambda Lambda is the 11th letter of the Greek alphabet. In the system of Greek numerals lambda has a value of 30. Lambda is related to the Phoenician letter Lamed . Letters in other alphabets that stemmed from lambda include the Roman L and the Cyrillic letter El... Precision	5 m/sec Second The second is a unit of measurement of time, and is the International System of Units base unit of time. It may be measured using a clock....	1 m/sec Second The second is a unit of measurement of time, and is the International System of Units base unit of time. It may be measured using a clock....
RV Radial velocity Radial velocity is the velocity of an object in the direction of the line of sight . In astronomy, radial velocity most commonly refers to the spectroscopic radial velocity... Stability	< 10 cm/s Second The second is a unit of measurement of time, and is the International System of Units base unit of time. It may be measured using a clock....	< 2 cm/s Second The second is a unit of measurement of time, and is the International System of Units base unit of time. It may be measured using a clock....
	4-VLT mode (D=16m) with RV=1m/sec Second The second is a unit of measurement of time, and is the International System of Units base unit of time. It may be measured using a clock....

Ref:

Sensitivity

Comparison between ESPRESSO and CODEX

See also