LARES (satellite)
| Company type | Satellite system |
|---|---|
| Industry | Space / Satellite technology |
| Founded | February 13, 2012 |
| Founder | Italian Space Agency (ASI) |
| Headquarters | Italy |
| Products | Passive laser ranging satellites (LARES 1 and LARES 2) |
| Parent | Italian Space Agency (ASI) |
LARES (Laser Relativity Satellite) is a passive satellite system managed by the Italian Space Agency (ASI).
LARES 1
The inaugural LARES satellite was deployed on 13 February 2012 at 10:00 UTC, utilizing the maiden flight of the Vega launcher from the ESA Centre Spatial Guyanais located in Kourou, French Guiana. This mission facilitates laser ranging and experimental verification of general relativity principles. The satellite features a compact, dense design engineered by Carlo Gavazzi Space, with a launch weight of 386.8 kg and a diameter measuring 36.4 cm. It maintains a low Earth orbit characterized by a periapsis of 1437 km, an apoapsis of 1451 km, and an orbital inclination of 69.49°, completing each revolution in roughly 115 minutes.
Composition
Manufactured from the tungsten alloy THA-18N, the satellite incorporates 92 cube-corner retroreflectors to enable precise laser tracking from terrestrial stations. With a diameter close to 36.4 cm and mass near 387 kg, LARES circulates at an altitude around 1440 km and an inclination angle of approximately 69.49 degrees. It is monitored by the International Laser Ranging Service. Due to its exceptional density, LARES stands as the densest artificial object in Earth orbit, thereby reducing perturbations such as those caused by solar radiation pressure.
Scientific goals
The primary objective of LARES is to quantify the Lense–Thirring effect with a targeted precision near 1%, as reported by principal investigator Ignazio Ciufolini and his research team; however, this level of accuracy remains debated within the scientific community. An evaluation based on 3.5 years of laser-ranging observations indicated an accuracy close to 4%, though this finding has been met with critical analysis.
In addition to its core mission, LARES contributes to further examinations of general relativity and supports investigations in geodynamics and satellite geodesy, enhancing its significance for both gravitational physics and Earth science disciplines.
LARES 2
The follow-up satellite, LARES 2, was launched on 13 July 2022 at 13:13:43 UTC aboard a Vega-C rocket. Originally planned for mid-2021, its deployment was delayed until mid-2022 due to complications arising from the COVID-19 pandemic.
LARES 2 seeks to refine measurements of the frame-dragging phenomenon with an anticipated precision of up to 0.2%, although some specialists have expressed skepticism regarding this target's achievability. Unlike its tungsten-based predecessor, LARES 2 utilizes a nickel alloy construction, reflecting a shift in material selection strategy.
See also
- LAGEOS satellites launched in 1976 with similar objectives
- List of laser ranging satellites
- List of passive satellites
- PAGEOS
- Project Echo
- Vega flight VV01
External links
- LARES Mission: official website.
- LARES - Testing of General Relativity on ASI's site.
- LARES - Pronto al via! article with images on ASI's site (Italian).
- LARES Satellite Information on ILRS website.