Free Rainbow Mars by Larry Niven

back, up, down. Nozzles poked past his short ribs, facing forward. He was wearing high explosives on his back, and he’d known this was coming. They were in balance between Mars gravity and centrifugal force. A flight stick would push up: no help.
    Miya affixed a flight stick to Svetz’s back for use when they got lower; then a blaster. “Want this too?”
    She was holding the needle gun. Svetz said, “Yes.”
    â€œYou sure?”
    â€œHabit. We don’t use blasters on any normal mission. We don’t want to kill anything in the past.”
    She turned and let him stickstrip a flight stick and blaster to her back, careful to keep it all clear of rocket nozzles.
    Miya went out first.
    The skyhook tree was fat in the middle, wider than any redwood. The black foliage only began much lower down.
    â€œLet’s do it,” Miya said. Facing the tree, she fired her rocket pack. Svetz fired his a moment later. It kicked him toward the tree. When her flame died, he cut his off too.

16
    â€¦ But most women, when they feel free to experiment with life, will go straight to the witches’ Sabbath. I myself respect them for it, and do not think that I could ever really love a woman who had not, at some time or other, been up on a broomstick.
    â€”Isak Dinesen, “The Old Chevalier,” from Seven Gothic Tales
    Â 
    The mid-trunk was glossy, void of detail but for a glittering silver thread. Svetz used his helmet to zoom on it. The thread split into two parallel lines.
    â€œMiya?”
    â€œI see it. The Martians have built a lift. That’s what you do with a Beanstalk.”
    Svetz asked, “They’d have used it to explore the solar system, wouldn’t they?”
    â€œTime is your thing, not mine. There are lots of little moons in the outer system, some almost as big as Mars. If Martians had been there, we’d have found something. Mars must have been just starting to reach out when something interrupted. Some disaster.”
    Svetz reset his helmet view. Unzoomed, the trunk was still coming close. Far around the curve was a creasing of the … bark? It stretched for several klicks, as if a silver-gray wing were folded along the trunk.
    â€œReady for retrothrust?”
    â€œI haven’t taken my fingers off those switches since you showed them to me.” The bark was very close.
    â€œGood. Hold off, though, Hanny. You see anything scary?”
    â€œLift cables. We’ve got Martians above and below. Those folds: you see them? I want a better look at those.”
    â€œRetrothrust,” Miya said. He didn’t see her fire, but he toggled switches with four fingertips. Nozzles poking past his ribs fired. His back plate pulled him backward. The trunk came softly up to meet him.
    There was nothing to cling to.
    Zeera’s voice: “Are you on the tree?”
    Miya: “Phoenix has landed. Hanny?”
    Svetz: “Snake is on the tree. Zeera, how’s your view?”
    Zeera: “I have views through both your helmet cameras. I will call you from Mons Olympus.”
    Blue flame puffed. The Minim spacecraft receded and was gone.

17
    Beanstalk. Universe tree of fairy tales; ladder or road to the heavens?… The rope trick of India is related to the belief in a stairway to heaven.
    â€”Dictionary of Mythology, Folklore and Symbols, by Gertrude Jobes
    Â 
    Svetz followed Miya around the trunk. The sun shown directly on them. Svetz deployed his silver cloak like a parasol, but he was still sweating. The porous pressure suit let his own sweat cool him. Otherwise he’d have steamed himself to death.
    He asked, “Should we be wearing sunblock?”
    â€œThe suits block UV,” Miya said.
    He drifted alongside the silver-gray crease. “Blanket big enough to cover a city. Square klicks of it,” he reported, for Miya and a later audience. He touched it. “Flimsy stuff.” He crawled under a fold of tissue-thin