J/AJ/154/115 Travel times of stars within about 300 lt-yr (Heller+, 2017)
Optimized trajectories to the nearest stars using lightweight high-velocity
photon sails.
Heller R., Hippke M., Kervella P.
<Astron. J., 154, 115-115 (2017)>
=2017AJ....154..115H 2017AJ....154..115H (SIMBAD/NED BibCode)
ADC_Keywords: Stars, nearby ; Stars, distances
Keywords: radiation mechanisms: general - solar neighborhood - space vehicles -
stars: individual (Alpha centauri, Sirius) -
stars: kinematics and dynamics
Abstract:
New means of interstellar travel are now being considered by various
research teams, assuming lightweight spaceships to be accelerated via
either laser or solar radiation to a significant fraction of the speed
of light (c). We recently showed that gravitational assists can be
combined with the stellar photon pressure to decelerate an incoming
lightsail from Earth and fling it around a star or bring it to rest.
Here, we demonstrate that photogravitational assists are more
effective when the star is used as a bumper (i.e., the sail passes "in
front of" the star) rather than as a catapult (i.e., the sail passes
"behind" or "around" the star). This increases the maximum
deceleration at α Cen A and B and reduces the travel time of a
nominal graphene-class sail (mass-to-surface ratio 8.6*10-4g/m2)
from 95 to 75 years. The maximum possible velocity reduction upon
arrival depends on the required deflection angle from α Cen A to
B and therefore on the binary's orbital phase. Here, we calculate the
variation of the minimum travel times from Earth into a bound orbit
around Proxima for the next 300 years and then extend our calculations
to roughly 22000 stars within about 300lt-yr. Although α Cen is
the most nearby star system, we find that Sirius A offers the shortest
possible travel times into a bound orbit: 69 years assuming 12.5% c
can be obtained at departure from the solar system. Sirius A thus
offers the opportunity of flyby exploration plus deceleration into a
bound orbit of the companion white dwarf after relatively short times
of interstellar travel.
Description:
Table2 lists our results for the maximum injection speeds and minimum
travel durations. The results have been obtained using numerical
trajectory simulations from our modified N-body integrator.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table2.dat 56 22683 An interstellar travel catalog to use
photogravitational assists for a full stop
--------------------------------------------------------------------------------
See also:
J/A+A/597/A137 : HD 123999 and Alpha Cen A and B OIFITS files (Kervella+, 2017)
J/A+A/508/1509 : Sky maps for hot Jupiters (Heller+, 2009)
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 22 A22 --- Name Star name (1)
24- 29 I6 km/s Speed [165/182947] Deceleration speed (maximum
injection speed)
31- 37 F7.1 yr Time [68.9/63540.7] Minimum travel duration from
Earth (2)
39- 43 F5.1 al Dist [4.2/316.9] Stellar distance to the solar
system (in light years)
45- 56 F12.6 Lsun Lum [0.00028/13919.9] Luminosity
--------------------------------------------------------------------------------
Note (1): Stars are ordered by increasing travel time from Earth. The
hypothetical lightsail has a nominal mass-to-surface ratio (σnom)
of 8.6*10-4g/m2.
Note (2): Travel times for different σ values scale as
σ/σnom1/2.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS]; Sylvain Guehenneux [CDS] 12-Feb-2018