Eta Corvi

[13] The IRAS satellite detected an excess of infrared radiation from this star, beyond what would normally be expected for a stellar object of this class.

[19][20] In 2010–2011, Carey Lisse of the Johns Hopkins University Applied Physics Laboratory and his group[11] analyzed the Spitzer IRS 5–35 μm spectrum of the warm, ~360K circumstellar dust and found that it showed clear evidence for warm, water- and carbon-rich dust at ~3 AU from the central star, in the system's habitable zone, uncoupled and in a separate reservoir from the system's extended sub-mm dust ring at 150 ± 20 AU.

Spectral features similar in kind and amplitude to those found for ultra-primitive (i.e., formed very early in the lifetime of the Eta Corvi system) ~10 Myr old cometary material were found (water ice and gas, olivines and pyroxenes, amorphous carbon and metal sulfides), in addition to emissions due to impact produced silica and high temperature/pressure carbonaceous phases.

A large amount, at least 3 x 1019 kg, of 0.1 – 1000 μm warm dust is present, in a roughly collisional equilibrium distribution with dn/da ~ a−3.5.

As part of this process, one or more of the excited KBOs was scattered onto an orbit that sent it into the inner system, where it collided with a planetary-class body at ~3 AU, releasing a large amount of thermally unprocessed, primitive ice and carbon-rich dust.

Their analysis suggests that the system is likely a good analogue for the Late Heavy Bombardment (LHB) processes that occurred in the early Solar System at 0.6–0.8 Gyr after the formation of the calcium–aluminium-rich inclusions (minerals such as olivines that are among the first solids condensed from the cooling protoplanetary disk) and is thus worthy of further detailed study in order to understand the nature of the LHB.

Artist's conception of a storm of comets in the Eta Corvi system, with a possible planet