Hyperscience International Journal https://hscience.org/index.php/hij <div class="about_site"> <p><strong style="box-sizing: border-box; font-weight: bolder; color: rgba(0, 0, 0, 0.87); font-family: 'Noto Serif', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen-Sans, Ubuntu, Cantarell, 'Helvetica Neue', sans-serif; font-size: 14px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: #ffffff; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">ISSN: 2821-3300</strong></p> <p><a href="https://hscience.org/index.php/hij" target="_blank" rel="bookmark noopener">Hyperscience International Journal</a> (HIJ) is an International <strong><em>Open Access Journal</em></strong> and publishes quarterly original research papers in Astronomy, Astrophysics, Cosmology, Radiotelescope, Quantum Mechanic Physics, (Theoretical &amp; Experimental Physics), Mathematical Physics, and related topics. The aim of <strong>HIJ</strong> is to publish original and high-quality research papers.</p> </div> Hyperjournal en-US Hyperscience International Journal 2821-3300 Optimal Leg Height of Landing Legs to Reduce Risk of ‎Damage from Regolith Ejecta by Retrorocket Exhausts https://hscience.org/index.php/hij/article/view/104 <p style="text-align: justify;">Over the past decade, there has been a rapid increase in rocket launches. 2022 was a record-breaking year for the ‎aerospace industry, with 180 successful rocket launches into orbit, 44 more than the previous year. Reducing as ‎many risks as possible is essential as interplanetary rocket launches and reusable booster landings become more ‎frequent. One such risk occurs when a rocket/booster lands. During the landing process, the retrorockets spray debris ‎from the loose ground, which may damage the rocket/landing module. Retrorockets are rocket engines that provide ‎a thrust opposing the spacecraft’s motion, causing it to decelerate. This paper studies the effect of landing leg height ‎on ejecta velocity, the volume of debris ejected, and ground surface temperature change.&nbsp; Four landing leg heights ‎were tested with an Estes® E-16 consumer model rocket motor: 0 mm, 50 mm, 75 mm, and 100 mm. The ‎experiment suggests that the optimal height above the ground’s surface for a simulated landing module based on ‎the volume and velocity of the ejecta is 50 mm. Landing legs that elevate a model rocket this height create an ‎average crater volume of 610.5 mL and a max crater diameter of 10.34 cm. After determining the optimal height, a ‎landing leg system was developed. This system was attached to an Aerodactyl TS® model rocket and utilized ‎landing legs that elevated the rocket to a height of 50 mm above the ground at landing.‎‎</p> Johan Karukayil Henry Love ‎ Copyright (c) 2023 Hyperscience International Journal https://creativecommons.org/licenses/by-nc/4.0 2023-09-01 2023-09-01 3 3 17 23 10.55672/hij2023pp17-23